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  • 1.
    Alhouayek, Mireille
    et al.
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience. Catholic Univ Louvain, Brussels, Belgium.
    Gouveia-Figueira, Sandra
    Umeå University, Faculty of Science and Technology, Department of Chemistry. Swedish Univ Agr Sci, Umea, Sweden.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Fowler, Christopher J.
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience.
    Involvement of CYP1B1 in interferon gamma-induced alterations of epithelial barrier integrity2018In: British Journal of Pharmacology, ISSN 0007-1188, E-ISSN 1476-5381, Vol. 175, no 6, p. 877-890Article in journal (Refereed)
    Abstract [en]

    BACKGROUND AND PURPOSE CYP1B1 and CYP1A1 are important extra-hepatic cytochromes, expressed in the colon and involved in the metabolism of dietary constituents and exogenous compounds. CYP1B1 expression is increased by pro-inflammatory cytokines, and it has been recently implicated in regulation of blood brain barrier function. We investigated its involvement in the increased permeability of the intestinal epithelial barrier observed in inflammatory conditions. EXPERIMENTAL APPROACH Epithelial monolayers formed by human T84 colon carcinoma cells cultured on transwells, were disrupted by incubation with IFN gamma (10 ng.mL(-1)). Monolayer integrity was measured using transepithelial electrical resistance. CYP1A1 and CYP1B1 inhibitors or inducers were applied apically. Potential mechanisms of action were investigated using RT-qPCR. KEY RESULTS IFN gamma disrupts the barrier integrity of the T84 monolayers and increases CYP1B1 and HIF1 alpha mRNA expression. CYP1B1 induction is inhibited by the NF-kappa B inhibitor ammonium pyrrolidinedithiocarbamate (100 mu M) but not by the HIF1 alpha inhibitor 3-(5-hydroxymethyl-2-furyl)-1-benzyl indazole (50 mu M). Inhibition of CYP1B1 with the selective inhibitor 2,4,3,5-tetramethoxystilbene (100 nM) partly reverses the effects of IFN gamma on epithelial permeability. CONCLUSIONS AND IMPLICATIONS These data suggest that increased expression of CYP1B1 is involved in the effects of IFN gamma on epithelial permeability. Inhibition of CYP1B1 counteracts the alterations of epithelial barrier integrity induced by IFN gamma and could thus have a therapeutic potential in disorders of intestinal permeability associated with inflammation.

  • 2.
    Andersson, Yvonne
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Lönnerdal, Bo
    Department of Nutrition, University of California, Davis, CA 95616.
    Graverholt, Gitte
    Arla Foods Ingredients, Aarhus, Denmark.
    Fält, Helen
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Hernell, Olle
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Formula feeding skews immune cell composition toward adaptive immunity compared to breastfeeding2009In: Journal of Immunology, ISSN 0022-1767, E-ISSN 1550-6606, Vol. 183, no 7, p. 4322-4328Article in journal (Refereed)
    Abstract [en]

    The ontogeny of the immune system and the effect thereon by type of infant feeding is incompletely understood. We analyzed frequencies and composition of immune cells in blood of breastfed (BF) and formula-fed (FF) infants at 1.5, 4, and 6 mo of age. Three formulas with the same protein concentration but with varying levels of alpha-lactalbumin and caseinoglycomacropeptide were compared. Twenty-nine exclusively BF infants served as reference, and 17 infants in each formula group completed the study. Whole blood and PBMCs were analyzed by flow cytometry and immunoflow cytometry, respectively. Leukocyte count of BF infants increased with time due to increased frequency of neutrophils. Lymphocyte count was high at 1.5 mo and was unchanged over time, as were the relative proportions of CD4+ alphabetaT cells, CD8+ alphabetaT cells, B cells, NK cells, and gammadeltaT cells. Most CD45R0+CD3+ cells were HLA-DR- and hence memory cells. Compared with breastfeeding, formula feeding resulted in a significant decrease in proportion of NK cells, but a significant increase in naive CD4+ alphabetaT cells and an elevated CD4-to-CD8 ratio, that is, 3.3 in the combined FF groups compared with 2.6 in the BF group. No significant differences were found between the three groups of FF infants. In conclusion, blood cells of lymphoid lineage did not change significantly in frequencies or composition from 1.5 to 6 mo of age in BF infants. In contrast, FF infants displayed an ongoing maturation of adaptive immunity cells and a delayed recruitment of innate immunity cells as compared with BF infants.

  • 3.
    Bas, A
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Forsberg, G
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry. Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Sjöberg, Veronika
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hernell, Olle
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Aberrant extrathymic T cell receptor gene rearrangement in the small intestinal mucosa: a risk factor for coeliac disease?2009In: Gut, ISSN 0017-5749, E-ISSN 1468-3288, Vol. 58, no 2, p. 189-195Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Coeliac disease is a small intestine enteropathy caused by permanent intolerance to wheat gluten. Gluten intake by patients with coeliac disease provokes a strong reaction by intestinal intraepithelial lymphocytes (IELs), which normalises on a gluten-free diet. AIM: To investigate whether impaired extrathymic T cell maturation and/or secondary T cell receptor (TCR) gene recombination in IELs are features of coeliac disease which could contribute to the failure of establishing tolerance to gluten.

    METHODS: Expression levels of the four splice-forms of recombination activating gene-1 (RAG1) mRNA and preT alpha-chain (preTalpha) mRNA were determined in IEL-subsets of children with coeliac disease and controls. Frequencies of RAG1 expressing IELs were determined by immunomorphometry.

    RESULTS: In controls, the RAG1-1A/2 splice-form selectively expressed outside the thymus, was dominant and expressed in both mature (TCR(+)) and immature (CD2(+)CD7(+)TCR(-)) IELs ( approximately 8 mRNA copies/18S rRNA U). PreTalpha was expressed almost exclusively in CD2(+)CD7(+)TCR(-) IELs ( approximately 40 mRNA copies/18S rRNA U). By contrast, RAG1 and preTalpha mRNA levels were low in patients with coeliac disease compared to controls, both with active disease and with inactive, symptom-free disease on a gluten-free diet (p values <0.01 for mature and <0.05 for immature IELs). Similarly, the frequencies of RAG1+ IELs were significantly lower in patients with coeliac disease compared to controls (p<0.001).

    CONCLUSIONS: Patients with coeliac disease appear to have an impaired capacity for extrathymic TCR gene rearrangement. This is an inherent feature, which probably plays a pivotal role in the failure to efficiently downregulate the T cell response to gluten.

  • 4.
    Bas, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Forsberg, Göte
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology. Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Utility of the housekeeping genes 18S rRNA, β-actin, and glyceraldehyde-3-phosphate-dehydrogenase (GAPDH) for normalisation in real-time quantitative RT-PCR analysis of gene expression in human T lymphocytes2004In: Scandinavian Journal of Immunology, ISSN 0300-9475, E-ISSN 1365-3083, Vol. 59, no 6, p. 566-573Article in journal (Refereed)
    Abstract [en]

    The accuracy of 18S rRNA, β-actin mRNA and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA as indicators of cell number when used for normalization in gene expression analysis of T lymphocytes at different activation stages was investigated. Quantitative real-time reverse transcriptase-polymerase chain reaction was used to determine the expression level of 18S rRNA, β-actin mRNA, GAPDH mRNA and mRNA for six cytokines in carefully counted samples of resting human peripheral blood mononuclear cells (PBMCs), intestinal lymphocytes and PBMCs subjected to polyclonal T-cell activation. The 18S rRNA level in activated and resting PBMCs and intestinal lymphocytes was essentially the same, while the levels of β-actin and GAPDH mRNAs fluctuated markedly upon activation. When isolated γδTCR+, CD4+ and CD8+ subpopulations were studied, 18S rRNA levels remained unchanged after 21 h of activation but increased slightly after 96 h. In contrast, there was a 30–70-fold increase of GAPDH mRNA/cell in these cell populations upon activation. Cytokine analysis revealed that only normalization to 18S rRNA gave a result that satisfactorily reflected their mRNA expression levels per cell. In conclusion, 18S rRNA was the most stable housekeeping gene and hence superior for normalization in comparative analyses of mRNA expression levels in human T lymphocytes.

  • 5. Bas, Anna
    et al.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Extrathymic TCR gene rearrangement in human small intestine: identification of new splice forms of recombination activating gene-1 mRNA with selective tissue expression.2003In: Journal of Immunology, ISSN 0022-1767, E-ISSN 1550-6606, Vol. 171, no 7, p. 3359-71Article in journal (Refereed)
    Abstract [en]

    Two new 5'-untranslated region (5'UTR) exons were identified in the human gene for the lymphocyte-specific endonuclease recombination activating gene-1 (RAG1) required for the somatic recombination yielding functional Ag receptors. These 5'UTR exons were used in three different splice forms by jejunal lymphocytes of the T cell lineage. RAG1 mRNA containing the previously described 5'UTR exon was not expressed in these cells. Conversely, one of the new 5'UTR exons was not expressed in thymus. The new RAG1 mRNA splice forms were all expressed in immature T cells (CD2(+)CD7(+)CD3(-)). This cell population also expressed high levels of mRNA for the pre-T alpha-chain. In situ hybridization demonstrated jejunal cells expressing the new splice forms of RAG1 mRNA, both intraepithelially and in lamina propria. Pre-T alpha-chain mRNA-expressing cells were detected at the same sites. These results strongly suggest ongoing TCR gene rearrangement in human small intestinal mucosa, yielding T cells specially adapted for this environment. This seems to be achieved by two parallel processes, extrathymic T cell development and peripheral Ag-driven TCR editing.

  • 6.
    Bitar, Aziz
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Aung, Kyaw Min
    Umeå University, Faculty of Medicine, Molecular Infection Medicine Sweden (MIMS). Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine). Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Wai, Sun Nyunt
    Umeå University, Faculty of Medicine, Molecular Infection Medicine Sweden (MIMS). Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine).
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Vibrio cholerae derived outer membrane vesicles modulate the inflammatory response of human intestinal epithelial cells by inducing microRNA-146a2019In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 9, article id 7212Article in journal (Refereed)
    Abstract [en]

    The small intestinal epithelium of Vibrio cholerae infected patients expresses the immunomodulatory microRNAs miR-146a and miR-155 at acute stage of disease. V. cholerae release outer membrane vesicles (OMVs) that serve as vehicles for translocation of virulence factors including V. cholerae cytolysin (VCC). The aim was to investigate whether OMVs, with and/or without VCC-cargo could be responsible for induction of microRNAs in intestinal epithelial cells and thereby contribute to immunomodulation. Polarized tight monolayers of T84 cells were challenged with OMVs of wildtype and a VCC deletion mutant of the non-O1/non-O139 (NOVC) V. cholerae strain V:5/04 and with soluble VCC. OMVs, with and without VCC-cargo, caused significantly increased levels of miR-146a. Increase was seen already after 2 hours challenge with OMVs and persisted after 12 hours. Challenge with soluble VCC caused significant increases in interleukin-8 (IL-8), tumour necrosis factor-α (TNF-α), CCL20, IL-1β, and IRAK2 mRNA levels while challenge with OMVs did not cause increases in expression levels of any of these mRNAs. These results suggest that V. cholerae bacteria release OMVs that induce miR-146a in order to pave the way for colonization by reducing the strength of an epithelial innate immune defence reaction and also preventing inflammation in the mucosa that factors like VCC can evoke.

  • 7.
    Bitar, Aziz
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    De, Rituparna
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry. Umeå University, Faculty of Medicine, Molecular Infection Medicine Sweden (MIMS).
    Melgar, Silvia
    Aung, Kyaw Min
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry. Umeå University, Faculty of Medicine, Molecular Infection Medicine Sweden (MIMS).
    Rahman, Arman
    Qadri, Firdausi
    Wai, Sun Nyunt
    Umeå University, Faculty of Medicine, Molecular Infection Medicine Sweden (MIMS).
    Shirin, Tahmina
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Induction of immunomodulatory miR-146a and miR-155 in small intestinal epithelium of Vibrio cholerae infected patients at acute stage of cholera2017In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 12, no 3, article id 0173817Article in journal (Refereed)
    Abstract [en]

    The potential immunomodulatory role of microRNAs in small intestine of patients with acute watery diarrhea caused by Vibrio cholerae O1 or enterotoxigenic Escherichia coli (ETEC) infection was investigated. Duodenal biopsies were obtained from study-participants at the acute (day 2) and convalescent (day 21) stages of disease, and from healthy individuals. Levels of miR-146a, miR-155 and miR-375 and target gene (IRAK1, TRAF6, CARD10) and 11 cytokine mRNAs were determined by qRT-PCR. The cellular source of microRNAs in biopsies was analyzed by in situ hybridization. The ability of V. cholerae bacteria and their secreted products to cause changes in microRNA- and mRNA levels in polarized tight monolayers of intestinal epithelial cells was investigated. miR-146a and miR-155 were expressed at significantly elevated levels at acute stage of V. cholerae infection and declined to normal at convalescent stage (P<0.009 versus controls; P = 0.03 versus convalescent stage, pairwise). Both microRNAs were mainly expressed in the epithelium. Only marginal down-regulation of target genes IRAK1 and CARD10 was seen and a weak cytokine-profile was identified in the acute infected mucosa. No elevation of microRNA levels was seen in ETEC infection. Challenge of tight monolayers with the wild type V. cholerae O1 strain C6706 and clinical isolates from two study-participants, caused significant increase in miR-155 and miR-146a by the strain C6706 (P<0.01). One clinical isolate caused reduction in IRAK1 levels (P<0.05) and none of the strains induced inflammatory cytokines. In contrast, secreted factors from these strains caused markedly increased levels of IL-8, IL-1β, and CARD10 (P<0.001), without inducing microRNA expression. Thus, miR-146a and miR-155 are expressed in the duodenal epithelium at the acute stage of cholera. The inducer is probably the V. cholerae bacterium. By inducing microRNAs the bacterium can limit the innate immune response of the host, including inflammation evoked by its own secreted factors, thereby decreasing the risk of being eliminated.

  • 8.
    Bitar, Aziz
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Kyaw, Min Aung
    Umeå University, Faculty of Medicine, Molecular Infection Medicine Sweden (MIMS).
    Marie-Louise, Hammarström
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Wai, Sun Nynt
    Umeå University, Faculty of Medicine, Molecular Infection Medicine Sweden (MIMS).
    Vibrio cholerae derived outer membrane vesicles modulate the inflammatory response ofhuman intestinal epithelial cells by inducing microRNA-146aIn: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322Article in journal (Refereed)
    Abstract [en]

    The small intestinal epithelium of Vibrio cholerae infected patients expresses the immunomodulatory microRNAs miR-146a and miR-155 at acute stage of disease. V. cholerae release outer membrane vesicles (OMVs) that serve as vehicles for translocation of virulencefactors including V. cholerae cytolysin (VCC). The aim was to investigate whether OMVs, with and/or without VCC-cargo could be responsible for induction of microRNAs in intestinal epithelial cells and thereby contribute to immunomodulation. Polarized tight monolayers of T84 cells were challenged with OMVs of wild-type and a VCC deletion mutant of the non-O1/non-O139 (NOVC) V. cholerae strain V:5/04 and with soluble VCC. OMVs, with and without VCC-cargo, caused significantly increased levels of miR-146a. Challenge with soluble VCC caused significant increases in interleukin-8 (IL-8), tumour necrosis factor-α(TNF-α), CCL20, IL-1β, and IRAK2 mRNA levels while challenge with OMVs did not causeany changes. Notably, OMVs from the VCC deficient mutant caused significant decreases in CCL20 and IL-18 mRNA levels. These results suggest that V. cholerae bacteria release OMVs that induce miR-146a in order to pave the way for colonization by reducing thestrength of an epithelial innate immune defence reaction and also preventing inflammation inthe mucosa that factors like VCC can evoke.

  • 9.
    Fahlgren, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Baranov, Vladimir
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Frängsmyr, L
    Zoubir, F
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Interferon-gamma tempers the expression of carcinoembryonic antigen family molecules in human colon cells: a possible role in innate mucosal defence.2003In: Scandinavian Journal of Immunology, ISSN 0300-9475, E-ISSN 1365-3083, Vol. 58, no 6, p. 628-41Article in journal (Refereed)
    Abstract [en]

    Four carcinoembryonic antigen-related cell adhesion molecule (CEACAM)s, i.e. CEA, CEACAM1, CEACAM6 and CEACAM7, are localized to the apical glycocalyx of normal colonic epithelium and have been suggested to play a role in innate immunity. The expression of these molecules in colon carcinoma cells was studied at the mRNA and protein levels after treatment with interferon-gamma (IFN-gamma), interleukin-1beta, live bacteria or lipopolysaccharide. The colon carcinoma cell lines LS174T and HT-29 were studied in detail using real-time quantitative reverse transcriptase-polymerase chain reaction, immunoflow cytometry and immunoelectron microscopy. IFN-gamma, but not the other agents, modified expression of CEA, CEACAM1 and CEACAM6. None of the agents upregulated CEACAM7 expression. Two expression patterns were seen. HT-29 cells, which initially showed low quantities of mRNAs and proteins, displayed marked upregulation of both mRNAs and proteins. LS174T cells transcribed stable high levels of mRNA before and after treatment. Additionally, IFN-gamma induced increased cell surface expression of CEA, CEACAM1 and CECAM6. IFN-gamma has two important effects on the expression levels of the CEA family molecules in colon epithelial cells: direct upregulation of CEACAM1 and promotion of cell differentiation resulting in increased expression of CEA and CEACAM6 and decreased expression of CEACAM7.

  • 10.
    Fahlgren, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Baranov, Vladimir
    Frängsmyr, Lars
    Zoubir, Fairouz
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Interferon-γ tempers the expression of carcinoembryonic antigen (CEA) family molecules – a role in innate colonic defence.2003In: Scandinavian Journal of Immunology, Vol. 58, no 6, p. 628-641Article in journal (Refereed)
  • 11.
    Fahlgren, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Danielsson, Åke
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Hammarstrom, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    β-Defensin-3 and -4 in intestinal epithelial cells display increased mRNA expression in ulcerative colitis2004In: Clinical and Experimental Immunology, ISSN 0009-9104, E-ISSN 1365-2249, Vol. 137, no 2, p. 379-385Article in journal (Refereed)
    Abstract [en]

    mRNA expression of two recently described human beta-defensins (hBD-3 and hBD-4) in epithelial cells of normal small and large intestine and the impact of chronic intestinal inflammation on their expression levels was investigated. Intestinal specimens from patients with ulcerative colitis (UC), Crohn's disease (CD) and controls with no history of inflammatory bowel disease were studied. hBD-3 and hBD-4 mRNAs were determined in freshly isolated epithelial cells by real-time quantitative reverse transcription-polymerase chain reaction (QRT-PCR) and by in situ hybridization. The effect of proinflammatory cytokines on hBD-3 and hBD-4 mRNA expression in colon carcinoma cells was also investigated. Purified epithelial cells of normal small and large intestine expressed both hBD-3 and hBD-4 mRNA, with higher expression levels of hBD-3 mRNA. In situ hybridization revealed higher levels of mRNA expression in the crypt- compared to the villus/luminal-compartment. Interferon (IFN)-gamma, but not tumour necrosis factor (TNF)-alpha or IL-1beta, augmented hBD-3 mRNA expression. None of these agents stimulated hBD-4 expression. Colonic epithelial cells from patients with UC displayed a significant increase in hBD-3 and hBD-4 mRNA compared to epithelial cells of controls. In contrast, small intestinal epithelial cells from CD patients did not show increased expression levels compared to the corresponding control cells. Moreover, Crohn's colitis did not show increased expression of hBD-4 mRNA, while the data are inconclusive for hBD-3 mRNA. We conclude that the chronic inflammatory reaction induced in the colon of UC patients enhances hBD-3 and hBD-4 mRNA expression in the epithelium, whereas in CD this is less evident.

  • 12.
    Fahlgren, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Danielsson, Åke
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Increased expression of antimicrobial peptides and lysozyme in colonic epithelial cells of patients with ulcerative colitis.2003In: Clinical Experimental Immunology, Vol. 131, no 1, p. 90-101Article in journal (Refereed)
  • 13.
    Forsberg, Göte
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Fahlgren, Anna
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hörstedt, Per
    Umeå University, Faculty of Science and Technology, Department of Plant Physiology. Umeå University, Faculty of Science and Technology, Umeå Plant Science Centre (UPSC).
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hernell, Olle
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Presence of bacteria and innate immunity of intestinal epithelium in childhood celiac disease2004In: American Journal of Gastroenterology, ISSN 0002-9270, E-ISSN 1572-0241, Vol. 99, no 5, p. 894-904Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES: Exposure to gliadin and related prolamins and appropriate HLA-DQ haplotype are necessary but not sufficient for contracting celiac disease (CD). Aberrant innate immune reactions could be contributing risk factors. Therefore, jejunal biopsies were screened for bacteria and the innate immune status of the epithelium investigated.

    METHODS: Children with untreated, treated, challenged CD, and controls were analyzed. Bacteria were identified by scanning electron microscopy. Glycocalyx composition and mucin and antimicrobial peptide production were studied by quantitative RT-PCR, antibody and lectin immunohistochemistry.

    RESULTS: Rod-shaped bacteria were frequently associated with the mucosa of CD patients, with both active and inactive disease, but not with controls. The lectin Ulex europaeus agglutinin I (UEAI) stained goblet cells in the mucosa of all CD patients but not of controls. The lectin peanut agglutinin (PNA) stained glycocalyx of controls but not of CD patients. mRNA levels of mucin-2 (MUC2), alpha-defensins HD-5 and HD-6, and lysozyme were significantly increased in active CD and returned to normal in treated CD. Their expression levels correlated to the interferon-gamma mRNA levels in intraepithelial lymphocytes. MUC2, HD-5, and lysozyme proteins were seen in absorptive epithelial cells. beta-defensins hBD-1 and hBD-2, carcinoembryonic antigen (CEA), CEA cell adhesion molecule-1a (CEACAM1a), and MUC3 were not affected.

    CONCLUSIONS: Unique carbohydrate structures of the glycocalyx/mucous layer are likely discriminating features of CD patients. These glycosylation differences could facilitate bacterial adhesion. Ectopic production of MUC2, HD-5, and lysozyme in active CD is compatible with goblet and Paneth cell metaplasia induced by high interferon-gamma production by intraepithelial lymphocytes.

  • 14.
    Forsberg, Göte
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Hernell, O
    Umeå University, Faculty of Medicine, Department of Clinical Sciences.
    Melgar, S
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Israelsson, A
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Paradoxical coexpression of proinflammatory and down-regulatory cytokines in intestinal T cells in childhood celiac disease2002In: Gastroenterology, ISSN 0016-5085, E-ISSN 1528-0012, Vol. 123, no 3, p. 667-678Article in journal (Refereed)
  • 15.
    Forsberg, Göte
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hernell, Olle
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Concomitant increase of IL-10 and pro-inflammatory cytokines in intraepithelial lymphocyte subsets in celiac disease.2007In: International Immunology, ISSN 0953-8178, E-ISSN 1460-2377, Vol. 19, no 8, p. 993-1001Article in journal (Refereed)
    Abstract [en]

    Celiac disease (CD) is a small intestinal enteropathy caused by permanent intolerance to wheat gluten. Active disease is characterized by a prominent cytokine response of intraepithelial lymphocytes (IELs) to gluten-containing diet with concomitant increase in expression of pro-inflammatory IFN-gamma and down-regulatory IL-10 without increase in tumor necrosis factor-alpha (TNF-alpha) or transforming growth factor-beta1 (TGF-beta1). The aim was to understand the local immune reaction by determining which intraepithelial T cell subsets produce the different cytokines. The three major IEL-subsets gammadeltaIELs, CD4(+)alphabetaIELs and CD8(+)alphabetaIELs, as well as CD94(+)CD8(+)alphabetaIELs, selectively expanded in active CD, were retrieved from small intestinal biopsies of children with active CD and controls and analyzed quantitatively for cytokine mRNA expression. In active CD, CD8(+)alphabetaIELs showed a significant increase in expression levels of both IFN-gamma and IL-10. CD8(+)alphabetaIELs were also the IEL subset with highest expression level per cell of both cytokines and constituted the cellular source for almost all IFN-gamma and most IL-10. Expression levels of both cytokines were higher in CD94(-)CD8(+)alphabetaIELs than CD94(+)CD8(+)alphabetaIELs. TNF-alpha levels were only increased in CD4(+)alphabetaIELs, which also showed the highest expression level per cell and constituted the major source of this cytokine. Interestingly, IL-10 was increased also in CD4(+)alphabetaIELs. Cytokine levels were low in gammadeltaIELs. 'Classical' CD94(-)CD8(+)alphabeta T cells within the epithelium are responsible for the excessive production of IFN-gamma, believed to drive the formation of intestinal lesions in active CD. Production of IL-10 may be a common feature of IELs producing pro-inflammatory cytokines, thereby attempting to limit inflammation in an autocrine fashion.

  • 16. Goodier, M R
    et al.
    Lundqvist, C
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Troye-Blomberg, M
    Langhorne, J
    Cytokine profiles for human V gamma 9+ T cells stimulated by Plasmodium falciparum.1995In: Parasite immunology (Print), ISSN 0141-9838, E-ISSN 1365-3024, Vol. 17, no 8, p. 413-23Article in journal (Refereed)
    Abstract [en]

    V gamma 9+ T cells from malaria non-exposed donors make proliferative responses to Plasmodium falciparum on in vitro stimulation. V gamma 9+ cells are strongly activated by components of the schizont stage of the parasite and by antigens released into the culture upon schizogony, while CD4+V gamma 9- cells are stimulated by the earlier stages of the parasite. Using reverse transcriptase-polymerase chain reaction (RT-PCR) we determined mRNA expression for 14 cytokines in highly purified V gamma 9+ cells enriched by positive selection after in vitro stimulation with P. falciparum schizont antigens. Interferon-gamma (IFN-gamma) and Tumor Necrosis Factor-alpha (TNF-alpha) were detected in all samples tested. The majority of samples also expressed TNF-beta, transforming growth factor-beta (TGF-beta) and Interleukin-8 (IL-8). Only occasional samples expressed IL-2, IL-5 and IL-10. Using the ELISPOT assay we found that a large fraction of the reactive V gamma 9+ cells produced IFN-gamma and that gamma delta T cells are the major producers of IFN-gamma in cultures stimulated with schizont antigens. The majority of V gamma 9+ cells in these cultures also express the membrane-bound form of TNF-alpha. Expression of these cytokines speaks for a cytolytic and/or inflammatory role of gamma delta cells in the response to malaria in non-exposed individuals.

  • 17.
    Hedberg, Maria E.
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Israelsson, Anne
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Moore, Edward R. B.
    Svensson-Stadler, Liselott
    Wai, Sun Nyunt
    Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine).
    Pietz, Grzegorz
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Sandström, Olof
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Hernell, Olle
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarstrom, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Prevotella jejuni sp nov., isolated from the small intestine of a child with coeliac disease2013In: International Journal of Systematic and Evolutionary Microbiology, ISSN 1466-5026, E-ISSN 1466-5034, Vol. 63, no 11, p. 4218-4223Article in journal (Refereed)
    Abstract [en]

    Five obligately anaerobic, Gram-stain-negative, saccharolytic and proteolytic, non-spore-forming bacilli (strains CD3 :27, CD3 :28(T), CD3 :33, CD3 :32 and CD3 :34) are described. All five strains were isolated from the small intestine of a female child with coeliac disease. Cells of the five strains were short rods or coccoid cells with longer filamentous forms seen sporadically. The organisms produced acetic acid and succinic acid as major metabolic end products. Phylogenetic analysis based on comparative 16S rRNA gene sequence analysis revealed close relationships between CD3 : 27, CD3 :28(T) and CD3 :33, between CD3 :32 and Prevotella histicola CCUG 55407(T), and between CD3 :34 and Prevotella melaninogenica CCUG 4944B(T). Strains CD3 : 27, CD3 :28(T) and CD3 :33 were clearly different from all recognized species within the genus Prevotella and related most closely to but distinct from P. melaninogenica. Based on 16S rRNA, RNA polymerase) beta-subunit (rpoB) and 60 kDa chaperonin protein subunit (cpn60) gene sequencing, and phenotypic, chemical and biochemical properties, strains CD3 :27, CD3 :28(T) and CD3 :33 are considered to represent a novel species within the genus Prevotella, for which the name Prevotella jejuni sp. nov. is proposed. Strain CD3 : 28(T) (=CCUG 60371(T)=DSM 26989(T)) is the type strain of the proposed novel species. All five strains were able to form homologous aggregates, in which tube-like structures were connecting individual bacteria cells. The five strains were able to bind to human intestinal carcinoma cell lines at 37 degrees C.

  • 18.
    Hedberg, Maria E
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Moore, Edward RB
    Svensson-Stadler, Liselott
    Hörstedt, Per
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Pathology.
    Baranov, Vladimir
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Hernell, Olle
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Wai, Sun Nyunt
    Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine).
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Lachnoanaerobaculum a new genus in Lachnospiraceae; characterization of Lachnoanaerobaculum umeaense gen. nov., sp. nov., isolated from human small intestine, Lachnoanaerobaculum orale gen. nov., sp. nov., isolated from saliva and reclassification of Eubacterium saburreum (Prevot) Holdeman and Moore 1970 as Lachnoanaerobaculum saburreum comb. nov.2012In: International Journal of Systematic and Evolutionary Microbiology, ISSN 1466-5026, E-ISSN 1466-5034, Vol. 62, no 11, p. 2685-2690Article in journal (Refereed)
    Abstract [en]

    Two new obligately anaerobic Gram-positive, saccharolytic and non-proteolytic spore-forming bacilli (strain CD3:22 and N1) are described. Strain CD3:22 was isolated from a biopsy of the small intestine of a child with celiac disease and strain N1 from the saliva of a healthy young man. The cells of both strains were observed to be filamentous with lengths of approximately 5 to >20 µm, some of them curving and with swellings. The novel organisms produced H2S, NH3, butyric acid and acetic acid as major metabolic end products. Phylogenetic analyses, based on comparative 16S rRNA gene sequencing, revealed close relationships (98 % sequence similarity) between the two isolates, as well as the type strain of Eubacterium saburreum CCUG 28089T and four other Lachnospiraceae bacterium/E. saburreum-like organisms. This group of bacteria were clearly different from any of the 19 known genera in the family Lachnospiraceae. While Eubacterium spp. are reported to be non-spore-forming, reanalysis of E. saburreum CCUG 28089T confirmed that the bacterium, indeed, is able to form spores. Based on 16S rRNA gene sequencing, phenotypic and biochemical properties, CD3:22 (CCUG 58757T) and N1 (CCUG 60305T) represent new species of a new and distinct genus, named Lachnoanaerobaculum, in the family Lachnospiraceae [within the order Clostridiales, class Clostridia, phylum Firmicutes]. Strain CD3:22 is the type strain of the type species, Lachnoanaerobaculum umeaense gen. nov., sp. nov., of the proposed new genus. Strain N1 is the type strain of the species, Lachnoanaerobaculum orale gen. nov., sp. nov. Moreover, E. saburreum CCUG 28089T is reclassified as Lachnoanaerobaculum saburreum comb. nov.

  • 19.
    Hedberg, Maria
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Hernell, Olle
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Baranov, Vladimir
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Wai, Sun Nyunt
    Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine).
    Moore, Edward
    Sahlgrenska Universitetssjukhuset, Göteborgs Universitet.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Clostridiales bacterium CD3:22-an anaerobic spore-forming bacterium isolated from small intestine in a celiac disease patient2010Report (Other academic)
  • 20.
    Ildgruben, A.
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry. Umeå University, Faculty of Medicine, Department of Clinical Sciences, Obstetrics and Gynaecology.
    Sjöberg, I.
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Obstetrics and Gynaecology.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Influence of Hormonal Contraceptives on the Immune Cells and Thickness of Human Vaginal Epithelium2003In: Obstetrics and Gynecology, ISSN 0029-7844, E-ISSN 1873-233X, Vol. 102, no 3, p. 571-582Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: To determine whether use of steroid hormone contraceptives modifies immune defense parameters of the vaginal epithelium in humans. METHODS: Vaginal biopsies were collected during the follicular and luteal phases in regularly menstruating women (controls) and in women using combined oral contraceptives, depot-medroxyprogesterone acetate injections, or levonorgestrel implants. Fifteen healthy women (aged 20-34 years) were enrolled in each group. Biopsies were analyzed in a blinded manner. Epithelial thickness was estimated by morphometry. Immune cells were analyzed by immunomorphometry with cell-type-specific monoclonal antibodies. RESULTS: The epithelium of controls harbored 241+/-35 leukocytes (CD45+ cells) per mm2 (mean+/-1 standard error of the mean), and the thickness was 261+/-16 microm. T lymphocytes (CD3+) dominated, and cytotoxic or suppressor T cells (CD8+) were more frequent than T helper cells (CD4:CD8 ratio: 0.7+/- 0.1). Macrophages (CD68+) constituted the second-largest population, followed by Langerhans cells (CD1a+). B cells, natural killer cells, monocytes, and granulocytes were generally absent. There were no significant differences between the follicular and luteal phases. The epithelium was significantly thicker in all three groups that used hormonal contraceptive (333+/-9 microm) compared with controls, and it exhibited superficial hyperplasia. The frequency of intraepithelial leukocytes (CD45+) was increased in depot-medroxyprogesterone acetate (P<.001) and levonorgestrel implant users (P<.04). In depot-medroxyprogesterone acetate users, this was explained by an increased frequency of the CD8+ T lymphocyte subset. CONCLUSION: Hormonal contraceptives induce hyperplasia of the vaginal epithelium. The significant changes in the intraepithelial leukocyte population in depot-medroxyprogesterone acetate and levonorgestrel implant users most probably reflect altered local immune capacity.

  • 21. Lundqvist, C
    et al.
    Melgar, S
    Yeung, M M
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Intraepithelial lymphocytes in human gut have lytic potential and a cytokine profile that suggest T helper 1 and cytotoxic functions.1996In: Journal of Immunology, ISSN 0022-1767, E-ISSN 1550-6606, Vol. 157, no 5, p. 1926-34Article in journal (Refereed)
    Abstract [en]

    The functional properties of intraepithelial lymphocytes (IEL) in normal human jejunum, ileum, and colon were investigated. Cytokine mRNA expression in IEL and enterocytes was determined by reverse transcriptase-PCR and IFN-gamma+ IEL by immunohistochemistry. Polyclonal activators were used to study proliferation and IFN-gamma secretion of IEL, and an anti-CD3-mediated redirected cytotoxicity assay was used to determine the lytic potential of IEL. Freshly isolated IEL at all three gut levels expressed mRNA for IL-1 beta, IL-2, IL-8, IFN-gamma, and TNF-alpha. Approximately 10% of IEL produced IFN-gamma, suggesting that IEL are immunologically active in vivo, performing similar functions along the intestine. IEL could be stimulated further in vitro to express IL-10, TNF-beta, and TGF-beta 1, while no Th2-type cytokines were induced, suggesting suppressive and cytolytic functions for IEL. All three jejunal IEL subpopulations (CD4-CD8-TCR-gamma delta+, CD4+TCR-alpha beta+, CD8+TCR-alpha beta+) expressed the same four cytokines, IL-2, IL-8, IFN-gamma, and TNF-alpha, indicating that CD4+TCR-alpha beta+ IEL are Th1 cells and that TCR-gamma delta+ IEL and CD8+TCR-alpha beta+ IEL include cytotoxic effector cells. Indeed, freshly isolated jejunal IEL displayed cytolytic activity. IEL were induced to proliferation by anti-CD3/TCR complex mAbs and leukoagglutinin, but not by Con A. There was no correlation between the magnitude of the proliferative response and the amounts of secreted IFN-gamma. Enterocytes expressed IL-1 beta and IL-8, and sometimes TNF-alpha. Although jejunal enterocytes express HLA-DR and hsp60, Ag presentation by these cells may induce anergy since their cytokine profile is different from that of classical APCs.

  • 22.
    Lundqvist, Carina
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Baranov, Vladimir
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Athlin, Leif
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Cytokine profile and ultrastructure of intraepithelial lymphocytes in human gut suggest that they are activated cells with T helper 1 and cytotoxic functionsManuscript (preprint) (Other academic)
  • 23.
    Lundqvist, Carina
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Baranov, Vladimir
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Athlin, Leif
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Intra-epithelial lymphocytes. Evidence for regional specialization and extrathymic T cell maturation in the human gut epithelium1995In: International Immunology, ISSN 0953-8178, E-ISSN 1460-2377, Vol. 7, no 9, p. 1473-1487Article in journal (Refereed)
    Abstract [en]

    The human gut epithelium is a unique immunological compartment, containing substantial amounts of intra-epithelial lymphocytes (IEL) with unknown functions. In this study we show that distinct and unusual subpopulations of IEL are present at different levels of human intestine. IEL phenotypes in normal jejunum, ileum and colon were compared using immunoflow cytometry and immunohistochemistry. The expression of mRNA for recombination-activating gene-1 (RAG-1) in IEL from all three levels was compared using reverse-transcription polymerase chain reaction, and the morphology of IEL in situ was determined using immunoelectron microscopy. Surface marker profiles of isolated intestinal epithelial cells at all three levels were also investigated. On average the proportion of TCR gamma delta IEL was comparable in jejunum than ileum and colon and varied in phenotype with gut level. CD4-CD8-TCR alpha beta IEL dominated in colon but were absent in jejunum. CD8+ TCR alpha beta IEL were present at all levels but only in jejunum did they constitute the majority of all IEL. CD4+ TCR alpha beta IEL were present in similar frequencies at all levels of the gut. In general, the majority of IEL had an activated phenotype (CD45RO+, alpha E beta 7+). Furthermore, IEL exhibited phenotypes which are rare in peripheral blood. The thymocyte markers CD1a and CD1c as well as the NK cell marker CD56 were expressed on a fraction of TCR alpha beta and TCR gamma delta IEL. A small population of 'null' cells (CD45+ TCR/CD#-CD20-CD14-CD15- cells) was also present at equal proportions along the gut. Jejunal but not colonic IEL expressed RAG-1 mRNA suggesting that extrathymic T cell maturation occurs in the epithelium of small intestine. RAG-1 was expressed in CD2+TCR/CD3- and CD3+/TCR-IEL. Ultrastructurally, IEL often formed small clusters and intimate contacts with epithelial cells, suggesting cell cooperation within the epithelium. Some IEL had pseudopodium-like extensions penetrating the epithelial basement membrane suggesting transmigration. Epithelial cells in small intestine but not colon expressed heat shock protein 60 and HLA-DR. CD1a, CD1b and CD1c were not expressed on intestinal epithelial cells at any level. The distinct surface marker profiles of IEL and epithelial cells along small and large intestine suggest functional regional specialization and are compatible with the hypothesis that TCR alpha beta IEL participate in immune reactions to lumenal antigens while TCR gamma delta IEL perform surveillance of the epithelium.

  • 24.
    Lundqvist, Carina
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Baranov, Vladimir
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Teglund, S
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Cytokine profile and ultrastructure of intraepithelial gamma delta T cells in chronically inflamed human gingiva suggest a cytotoxic effector function1994In: Journal of Immunology, ISSN 0022-1767, E-ISSN 1550-6606, Vol. 153, no 5, p. 2302-2312Article in journal (Refereed)
    Abstract [en]

    We have shown that gamma delta T cells in human gingiva have an intraepithelial location and, that in the chronic inflammatory disease periodontitis, the expression of CD45RO and CD8 or CD4 is induced on gamma delta T cells. To study the role of gamma delta T cells in local antibacterial responses, we determined the cytokine profiles of isolated human gingival cells. Different T cell subpopulations, isolated by positive selection with mAb-coated magnetic beads and macrophages, as well as epithelial cells, were analyzed for expression of mRNA for 15 cytokines by reverse transcriptase-PCR. The ultrastructure of gingival gamma delta T cells was also studied. The gamma delta T cells expressed mRNA for IFN-gamma, TNF-alpha, TGF-beta 1, and IL-6. Expression of IFN-gamma was a consequence of inflammation. CD4+ gamma delta T cells expressed IFN-gamma only, whereas CD8+ gamma delta T cells expressed all four cytokines. CD8+ cells expressing IFN-gamma, TNF-alpha, and IL-6 in combination suggest a cytotoxic effector function. Gingival gamma delta T cells contained cytoplasmic electron-dense membrane-bound granules and multivesicular bodies that are ultrastructural characteristics of cytotoxic cells. Epithelial cells from inflamed gingiva expressed HLA-DR, CD1a, CD1c, and heat shock protein 60 on the cell surface. They also expressed mRNA for IL-1 beta, IL-6, IL-8, TNF-alpha, and TGF-beta 1. Thus, epithelial cells may function as accessory cells in immune activation and, at the same time, be target cells for CD8+ gamma delta T cells reactive with CD1 Ag or heat shock protein. These results suggest that gamma delta T cells constitute a first line of defense in gingiva, preventing entrance of pathogens by cytotoxicity against infected and stressed epithelial cells, and by control of epithelial cell growth through secretion of regulatory cytokines.

  • 25.
    Lundqvist, Carina
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    T-cell receptor gamma delta-expressing intraepithelial lymphocytes are present in normal and chronically inflamed human gingiva1993In: Immunology, ISSN 0019-2805, E-ISSN 1365-2567, Vol. 79, no 1, p. 38-45Article in journal (Refereed)
    Abstract [en]

    The phenotypic profile of leucocytes in diseased and normal gingival tissue was studied in situ and in isolated gingival mononuclear cell (GMC) preparations. T-cell receptor (TcR)gamma delta + cells showed preferential localization to epithelium, both in normal and inflamed gingiva, and were present in crevicular as well as oral epithelium. In normal gingiva > or = 30% of the isolated leucocytes expressed TcR gamma delta, of which the majority were CD4- CD8-, and expressed CD45RA. The proportion of TcR gamma delta + cells in GMC from periodontitis tissue varied between 2 and 32%. In contrast to normal gingiva the majority of TcR gamma delta + cells in diseased tissue were CD8+ and expressed CD45RO. Thus expression of the CD8 antigen on gingival TcR gamma delta + cells is probably a consequence of immune activation. Numerous Langerhans' cells and keratinocytes expressing the major histocompatibility complex (MHC) class I-like antigen, CD1, were present within normal and inflamed gingival epithelium in close proximity to the TcR gamma delta + cells. Most CD1a+ cells were scattered within oral epithelium. CD1c+ cells were localized close to the basal layer of crevicular epithelium. No CD1b+ cells were found. TcR alpha beta + cells, CD4+ and B cells were restricted to lamina propria of periodontitis lesions. The presence of intraepithelial TcR gamma delta + cells in normal gingiva suggests that they constitute the 'first line of defence' against the potentially harmful microflora in the oral cavity. Induction of CD8 and CD45RO antigens on TcR gamma delta + cells in periodontitis tissue indicate that they play a significant role in the disease. CD1 molecules on Langerhans' cells and keratinocytes may be the restriction elements for the CD8+ TcR gamma delta + cells.

  • 26.
    Lundqvist, Carina
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Athlin, Leif
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Isolation of functionally active intraepithelial lymphocytes and enterocytes from human small and large intestine1992In: JIM - Journal of Immunological Methods, ISSN 0022-1759, E-ISSN 1872-7905, Vol. 152, no 2, p. 253-263Article in journal (Refereed)
    Abstract [en]

    A mild purification method has been developed for the isolation of human intraepithelial lymphocytes (IEL) and enterocytes from the same individual. The isolation procedure includes mechanical disruption of the mucosal layer, treatment with reducing agent and sedimentation followed by Percoll gradient centrifugation. Finally, epithelial cells are removed from the IEL fraction using magnetic beads coated with the anti-epithelial antigen monoclonal antibody (mAb) BerEP4. Leucocytes are removed from the enterocyte fraction using magnetic beads coated with mAbs directed against common leucocyte antigen (CD45). Using this procedure IEL and enterocytes have been isolated from apparently normal jejunal, ileal and colonic tissue specimens. Recoveries of IEL were 7 x 10(5), 4 x 10(5) and 1 x 10(5)/cm2 mucosa from jejunum, ileum and colon respectively. 1-2 x 10(6) enterocytes/cm2 mucosa were recovered from small intestine while the corresponding value for colonic biopsies was approximately 2 x 10(5) enterocytes/cm2. The IEL fraction was pure as judged by the low percentages of B cells, macrophages and BerEP4 positive cells (less than 4%) present in the purified fraction. The enterocyte fraction contained less than 2% CD45+ cells. The two cell fractions were viable and expanded in vitro. Enterocytes expanded spontaneously while IEL required initial stimulation with mitogens. The isolation procedure described here will make it possible to study the function of human IEL, interactions between IEL and enterocytes and the role of both cell types in local immunity.

  • 27.
    Melgar, S
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Öberg, Åke
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Danielsson, Åke
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Cytolytic capabilities of lamina propria and intraepithelial lymphocytes in normal and chronically inflamed human intestine2004In: Scandinavian Journal of Immunology, ISSN 0300-9475, E-ISSN 1365-3083, Vol. 60, no 1-2, p. 167-177Article in journal (Refereed)
    Abstract [en]

    Cell-mediated lymphocyte cytotoxicity in ileum and colon of patients with ulcerative colitis (UC), Crohn's disease (CD) and controls was investigated. Frequencies of cells expressing perforin and Fas-ligand (FasL) were determined by immunomorphometry. mRNA expression of perforin, granzyme B and FasL in T cells and subsets was assayed by reverse transcriptase-polymerase chain reaction. Cytotoxicity of intraepithelial and lamina propria lymphocytes was analysed without ex vivo activation in three functional assays: (1) anti-CD3-dependent T-cell receptor (TCR)-/CD3-mediated redirected cytotoxicity, (2) Fas-/FasL-mediated TCR-/CD3-independent cytotoxicity and (3) natural killer (NK) cell cytotoxicity. Inflammation in ileum of CD patients caused increased frequency of perforin-expressing cells and enhanced perforin-dependent TCR-/CD3-mediated cytotoxicity. In contrast, lymphocytes in the inflamed colon of UC or Crohn's colitis patients did not display this cytotoxicity nor did lymphocytes of normal colon. Normal colon lymphocytes showed spontaneous Fas-/FasL-mediated cytotoxicity. This activity was retained but not enhanced in inflamed UC colon. In contrast, a significant increase of FasL-expressing cells was seen in situ. Inflammation did not induce NK cell activity in colonic lymphocytes. Intestinal lymphocytes comprise effectors active in two different cytolytic processes. 'Classical' cytotoxic T lymphocytes in small intestine and lymphocytes executing TCR-/CD3-independent FasL-/Fas-mediated killing of unknown biological role present throughout the intestinal mucosa. Ongoing normal cytolytic processes seem to be enhanced by chronic inflammation.

  • 28. Melgar, S
    et al.
    Yeung, M M-W
    Bas, A
    Forsberg, G
    Suhr, O
    Oberg, A
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Danielsson, A
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Over-expression of interleukin 10 in mucosal T cells of patients with active ulcerative colitis.2003In: Clinical and Experimental Immunology, ISSN 0009-9104, E-ISSN 1365-2249, Vol. 134, no 1, p. 127-37Article in journal (Refereed)
    Abstract [en]

    Ulcerative colitis (UC), a chronic inflammatory bowel disease, exhibits pronounced increase of T lymphocytes in the inflamed mucosa. To understand the role of intestinal T lymphocytes in the pathogenesis of UC their cytokine production in the mucosa was analysed. Intestinal T lymphocytes of UC, Crohn's disease and control patients were analysed for cytokine mRNA levels by real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR) directly after isolation without in vitro stimulation. Frequencies of cytokine positive cells were determined in UC and control colon by immunomorphometry. T lymphocytes in normal colon expressed interleukin (IL)-2, interferon (IFN)-gamma, tumour necrosis factor (TNF)-alpha and transforming growth factor (TGF)-beta1, but not IL-4, IL-5 or IL-10. In UC, a highly significant increase in IL-10 mRNA levels in T lymphocytes and an increased frequency of IL-10 positive cells was seen in colon. IL-10 mRNA levels were also elevated in T lymphocytes of the non-inflamed ileum and correlated with disease activity at both locations. CD4+ T lymphocytes were the major source of IL-10 mRNA. IL-2, IFN-gamma and TNF-alpha mRNA levels were decreased in colonic T lymphocytes, and virtually no IL-2, IFN-gamma, TNF-alpha or TGF-beta positive cells were detected in basal lymphoid aggregates. However, scattered IL-10 positive cells were found here. Lamina propria outside the aggregates contained IL-10-, IFN-gamma, TNF-alpha and TGF-beta but not IL-2 positive cells. T cells of UC patients did not express IL-4 or IL-5. Taken, together the data suggest a generalized activation of IL-10 producing CD4+ T cells along the intestine of UC patients. The local environment seems to determine the biological consequences of elevated IL-10.

  • 29. Melgar, Silvia
    et al.
    Bas, Anna
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Human small intestinal mucosa harbours a small population of cytolytically active CD8+ alphabeta T lymphocytes.2002In: Immunology, Vol. 106, no 4, p. 476-485Article in journal (Refereed)
  • 30.
    Melgar, Silvia
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Yeung, MM
    Forsberg, G
    Omholt, K
    Suhr, Ole
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Öberg, Å
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Danielsson, Åke
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Medicine.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Mucosal T cells of patients with active ulcerative colitis express increased levels of the immune-regulatory cytokine interleukin-10Article in journal (Other academic)
  • 31.
    Mincheva-Nilsson, Lucia
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Baranov, Vladimir
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Yeung, M M
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Immunomorphologic studies of human decidua-associated lymphoid cells in normal early pregnancy.1994In: Journal of Immunology, ISSN 0022-1767, E-ISSN 1550-6606, Vol. 152, no 4, p. 2020-32Article in journal (Refereed)
    Abstract [en]

    Human decidual lymphocytes from early, normal pregnancy were characterized in situ with respect to ultrastructure and distribution of subsets. The ultrastructure of isolated decidual gamma delta T cells was also studied. CD45+ cells comprised 11 +/- 2% of all decidual cells. The majority were localized in large lymphoid cell clusters (LCC), near endometrial glands, or as intraepithelial lymphocytes (IEL) in glandular epithelium. The major cell populations in LCC were CD56+TCR-gamma delta+ cells, CD56+ cells, TCR-alpha beta+CD4+ cells, and TCR-alpha beta+CD8+ cells. All expressed activation markers (CD45RO, Kp43, and/or HML-1) and MHC class II Ag (HLA-DR, HLA-DP, and/or HLA-DQ). No B cells were found. Almost all IEL were activated TCR-gamma delta+ cells (CD56+ and CD56-). The glandular epithelial cells expressed heat shock protein 60 at the basolateral side facing the TCR-gamma delta+ IEL. Decidual lymphocytes displayed cytoplasmic processes, microvilli, characteristic cytoplasmic granules, and had intimate contact with neighboring cells. Lymphocytes in the outer rim of LCC and the stroma showed signs of cellular movement. Two main morphotypes of gamma delta T cells could be distinguished. One had single microvilli, membrane-bound granules, and nuclear inclusions. The other had many microvilli, nonmembrane-bound granules and cytoplasmic multivesicular bodies. Our data suggest that LCC are centers of immune reactivity where T and NK cells become activated. The activated cells may guard against infections and undue trophoblast invasion and/or be involved in modulating the local maternal immune system toward unresponsiveness against the semiallogeneic fetus.

  • 32.
    Mincheva-Nilsson, Lucia
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Juto, Per
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Virology.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Human milk contains proteins that stimulate and suppress T lymphocyte proliferation.1990In: Clinical and Experimental Immunology, ISSN 0009-9104, E-ISSN 1365-2249, Vol. 79, no 3, p. 463-9Article in journal (Refereed)
    Abstract [en]

    The modulatory effect of human milk proteins from colostrum and late milk on the proliferative response of human T lymphocytes activated by mitogens (OKT3 and leucoagglutinin from Phaseolus vulgaris) and alloantigens was studied. High concentrations (10-100 micrograms/ml) of crude colostral milk proteins had an inhibitory effect on T cell growth while low concentrations (0.1-1 microgram/ml) enhanced T cells growth. In contrast, proteins from late milk did not inhibit T lymphocyte proliferation while the enhancing effect was retained. Colostrum was fractionated by ammonium sulphate precipitation and gel filtration on sepharose 6B. The inhibitory activity was recovered in a protein fraction containing lactoferrin as its major component. Lactoferrin was, however, not responsible for the observed inhibition. On the contrary, lactoferrin in most cases augmented the proliferative response induced by polyclonal activators. The inhibitory activity was found to bind concanavalin A-sepharose suggesting an association with glycoprotein. Inhibitory fractions contained glycoproteins of the following molecular sizes 26, 74/76 (doublet), 84, 145 and 160 kD under reducing conditions. The inhibitory effect appeared to be lymphocyte specific since the active fraction did not inhibit the growth of tissue culture cells (HeLa cells and human fibroblasts) or bacteria. Furthermore, the fraction was not toxic for lymphocytes. The inhibitory colostrum factor may prevent the newborn from overreacting immunologically against the environmental antigens encountered at birth.

  • 33.
    Mincheva-Nilsson, Lucia
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Activated human gamma delta T lymphocytes express functional lactoferrin receptors.1997In: Scandinavian Journal of Immunology, ISSN 0300-9475, E-ISSN 1365-3083, Vol. 46, no 6, p. 609-18Article in journal (Refereed)
    Abstract [en]

    Lactoferrin (Lf), an iron-binding protein in milk, mucosal secretions and neutrophil granules has bactericidal properties and is a source of iron for breast-fed infants. In this paper the authors show that most in vivo activated lymphocytes, i.e. freshly isolated lymphocytes from first trimester human decidua, and most in vitro activated human blood lymphocytes, express lactoferrin receptors (Lf-R), while unstimulated blood lymphocytes do not. All major lymphocyte subsets, i.e. alpha beta T cells, gamma delta T cells, CD8+ T cells, CD4+ T cells, B cells and NK cells, express Lf-R after activation. The proportion of Lf-R expressing activated gamma delta T cells is significantly larger than that of activated alpha beta T cells. Lf-R and transferrin receptors (Tr-R/CD71) show the same kinetics of appearance on activated blood lymphocytes and are, to a large extent, expressed on the same cells. However, 35% of decidual lymphocytes and 15% of activated blood lymphocytes express Lf-R only. Addition of Lf to cultures containing an optimal concentration of Tr augments the proliferative response to polyclonal T cell activators and alloantigens, suggesting that presently used standard culture conditions for in vitro activation are suboptimal in particular for gamma delta T cells. Lf-R on decidual lymphocytes contain bound Lf, which probably is produced locally. The results suggest that Lf is a growth-supporting factor, especially important in local immune responses in the mucosa.

  • 34.
    Mincheva-Nilsson, Lucia
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Human decidual leukocytes from early pregnancy contain high numbers of gamma delta+ cells and show selective down-regulation of alloreactivity.1992In: Journal of Immunology, ISSN 0022-1767, E-ISSN 1550-6606, Vol. 149, no 6, p. 2203-11Article in journal (Refereed)
    Abstract [en]

    The mononuclear lymphoid cell population in human pregnant uterus mucosa, decidua, from early normal pregnancies was studied phenotypically and functionally. The phenotype was determined in situ by immunohistochemistry, and in isolated decidual mononuclear cell preparations by immunofluorescence and flow cytometry. A mild isolation procedure of gentle mechanical disruption followed by density gradient centrifugation was used. Leukocytes comprised a large part of the decidual tissue. They were present in aggregates mainly situated adjacent to the glandular epithelium. In addition, individual leukocytes were present intraepithelially, as well as scattered between the stromal cells and around vessels and lacunes. Four lymphocyte populations of approximately the same size were identified: TCR gamma delta+/CD56+ cells, TCR gamma delta+/CD56- cells, TCR gamma delta-/CD56+ cells, and TCR alpha beta+/CD8+ cells. TCR gamma delta- expressing cells comprised about 60% of the T cells. They were CD4-/CD8-, and about half of the TCR gamma delta+ cells expressed the memory/activation marker CD45RO. The Kp 43 Ag, earlier described on activated CD56+ and TCR gamma delta+ cells in peripheral blood, was essentially only expressed on the TCR gamma delta-/CD56+ cell population in decidua. At least 50% of the TCR alpha beta+ cells were CD8+. The function(s) of either one of these populations might be to prevent immunologic reactions against the fetus, to protect the uterus from unwanted extensive invasion of trophoblasts, or to protect the uteroplacental unit from infection. Decidual T cells did not respond to stimulation by alloantigens or mitogenic anti-CD3 mAb but responded to the same extent as PBMC to mitogenic lectins. The surface density of the TCR/CD3 complex was low on freshly isolated decidual lymphocytes, but could be up-regulated upon stimulation with PMA/Ionomycin. Local selective down-regulation of surface expression of the TCR/CD3 complex and of activation involving this complex might be one of the mechanisms by which a maternal immunologic reaction against the semiallogeneic fetus is prevented.

  • 35.
    Mincheva-Nilsson, Lucia
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Immunomodulatory role of decidual epithelial cells in early human pregnancyManuscript (preprint) (Other academic)
  • 36.
    Mincheva-Nilsson, Lucia
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Kling, M
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Nagaeva, O
    Sundqvist, K G
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Baranov, Vladimir
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Gamma delta T cells of human early pregnancy decidua: evidence for local proliferation, phenotypic heterogeneity, and extrathymic differentiation.1997In: Journal of Immunology, ISSN 0022-1767, E-ISSN 1550-6606, Vol. 159, no 7, p. 3266-77Article in journal (Refereed)
    Abstract [en]

    The uterine mucosa in pregnancy, the decidua, allows placenta formation and survival of the fetus despite the fact that it is semiallogeneic. Decidua contains large numbers of lymphocytes, of which CD56+ cells dominate, followed by T cells expressing either alpha beta or gamma delta TCR. We have investigated the developmental relationship between the CD56- and TCR gamma delta-expressing cells in early pregnancy decidua using dual labeling immunoelectron microscopy, immunoflow cytometry, and cell fractionation. Lymphocyte subpopulations were, in addition, analyzed for expression of the cytokine receptor for IL-7 and c-kit and for mRNA expression of recombinase-activating genes 1 and 2. Four different cell populations could be distinguished: CD56+bright, CD56+dim/TCR gamma delta+low, CD56+dim/TCR gamma delta+high, and TCR gamma delta+low. Recombinase-activating genes 1 and 2 were expressed in the CD56+bright cells and to a limited degree in CD56+dim/TCR gamma delta+low cells. c-kit was preferentially expressed on the CD56+bright cells, while IL-7R was preferentially expressed on CD56+dim/TCR gamma delta+low and CD56+dim/TCR gamma delta+high cells. The CD56+dim TCR gamma delta+low and CD56+dim/TCR gamma delta+high cells displayed the characteristic morphology of large granular lymphocytes, while single positive TCR gamma delta+low cells were usually smaller and did not contain cytoplasmic granules. The gamma delta 1 gene segment was almost exclusively used in the TCR. Gamma delta T cells in mitosis were seen. We suggest that human early pregnancy decidua is a transient site for extrathymic maturation and that the progenitors of TCR gamma delta+ cells are bone marrow-derived immature cells expressing the CD56 (neural cell adhesion molecule) homing receptor.

  • 37.
    Mincheva-Nilsson, Lucia
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Nagaeva, Olga
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Sundqvist, Karl-Gösta
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Clinical Immunology.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Baranov, Vladimir
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    gammadelta T cells of human early pregnancy decidua: evidence for cytotoxic potency.2000In: International Immunology, ISSN 0953-8178, E-ISSN 1460-2377, Vol. 12, no 5, p. 585-96Article in journal (Refereed)
    Abstract [en]

    The immune compromise in decidua allows a semiallogeneic fetus to survive without impairing the ability of the maternal immune system to fight infections. Cytotoxic mechanisms are likely to be important in this compromise. Using RT-PCR, immunoflow cytometry and immunoelectron microscopy, the cytotoxic potential of isolated human decidual gammadelta T cells was studied. mRNA for perforin (Pf), granzymes A and B, granulysin and Fas ligand (FasL) was simultaneously expressed in decidual gammadelta T cells. Pf and FasL were not expressed on the cell surface. However, the cells constitutively synthesized Pf and stored it in cytolytic granules. Within the granules Pf mainly resided in the granule core formed by Pf-containing microvesicles. Ultrastructurally, three groups of Pf-containing granules were distinguished. They probably represent different stages of granule maturation in a process where Pf-containing microvesicles first attach to the core cortex and then are translocated across the cortex into the core. Presynthesized FasL was also stored in the core and microvesicles of the cytolytic granules. Upon degranulation by ionomycin/Ca(2+) treatment, FasL was rapidly translocated to the cell surface, demonstrating that its surface expression was not controlled by de novo biosynthesis. Thus decidual gammadelta T cells appear to perform Pf- and FasL-mediated cytotoxicity utilizing a common secretory mechanism based on cytolytic granule exocytosis. The first cytochemical visualization of lipids in the cytolytic granules is provided. These intragranular lipids probably wrap up the core and participate in packaging of the cytotoxic proteins as well as in the killing process. An ultrastructural model of a cytolytic granule is presented.

  • 38.
    Myleus, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Stenlund, Hans
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Hernell, Olle
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Gothefors, Leif
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Persson, Lars-åke
    Women's and Children's Health, International Maternal and Child Health, Uppsala University, Uppsala, Sweden.
    Ivarsson, Anneli
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Early vaccinations are not risk factors for Celiac Disease2012In: Pediatrics, ISSN 0031-4005, E-ISSN 1098-4275, Vol. 130, no 1, p. E63-E70Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES: To investigate if changes in the national Swedish vaccination program coincided with changes in the celiac disease (CD) incidence rate in infants (ie, the Swedish CD Epidemic), and to assess the potential association between these vaccinations and CD risk.

    METHODS: All studies were based on the National Swedish Childhood Celiac Disease Register. Using an ecological approach, we plotted changes over time in the national vaccination program in the graph displaying CD incidence rate. A population-based incident case-referent study of invited infants was performed. Exposure information was received through a questionnaire and child health clinic records. Vaccines explored were diphtheria/tetanus, pertussis (acellular), polio (inactivated), Haemophilus influenzae type b (conjugated), measles/mumps/rubella, and live attenuated bacillus Calmette-Guerin (BCG) in children with increased tuberculosis risk. Findings were subjected to a birth cohort analysis.

    RESULTS: Introduction of pertussis vaccine coincided in time with decreasing CD incidence rates. In the infant case-referent study, however, neither vaccination against pertussis (odds ratio 0.91; 95% confidence interval 0.60-1.4), nor against Haemophilus influenzae type b or measles/mumps/rubella was associated with CD. Coverage for the diphtheria/tetanus and polio vaccines was 99%. BCG was associated with reduced risk for CD (adjusted odds ratio 0.54; 95% confidence interval 0.31-0.94). Discontinuation of general BCG vaccination did not affect the cumulative incidence of CD at age 15 years.

    CONCLUSIONS: Early vaccinations within the national Swedish program were not associated with CD risk, nor could changes in the program explain the Swedish epidemic. A protective effect by BCG was suggested, which could be subject to further studies. Pediatrics 2012;130:e63-e70

  • 39.
    Myléus, Anna
    et al.
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Hernell, Olle
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Gothefors, Leif
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Paediatrics.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Persson, Lars-Åke
    International Maternal and Child Health, Department of Women's and Children's Health, Uppsala University, Uppsala, Sweden.
    Stenlund, Hans
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Ivarsson, Anneli
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Early infections are associated with increased risk for celiac disease: an incident case-referent study2012In: BMC Pediatrics, ISSN 1471-2431, E-ISSN 1471-2431, Vol. 12, no 1, p. 194-Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Celiac disease is defined as a 'chronic small intestinal immune-mediated enteropathy precipitated by exposure to dietary gluten in genetically predisposed individuals'. Sweden has experienced an "epidemic" of celiac disease in children below two years of age. Celiac disease etiology is considered multifactorial; however, little is known regarding potential risk- or protecting factors. We present data on the possible association between early infectious episodes and celiac disease, including their possible contribution to the Swedish celiac disease epidemic.

    METHODS: A population-based incident case-referent study (475 cases, 950 referents) with exposure information obtained via a questionnaire (including family characteristics, infant feeding, and the child's general health) was performed. Celiac disease cases were diagnosed before two years of age, fulfilling the diagnostic criteria of the European Society for Pediatric Gastroenterology, Hepatology and Nutrition. Referents were randomly selected from the national population register after fulfilling matching criteria. The final analyses included 954 children, 373 (79%) cases and 581 (61%) referents, with complete information on main variables of interest in a matched set of one case with one or two referents.

    RESULTS: Having three or more parental-reported infectious episodes, regardless of type of infection, during the first six months of life was associated with a significantly increased risk for later celiac disease, and this remained after adjusting for infant feeding and socioeconomic status (odds ratio [OR] 1.5; 95% confidence interval [CI], 1.1-2.0; P=0.014). The celiac disease risk increased synergistically if, in addition to having several infectious episodes, infants were introduced to dietary gluten in large amounts, compared to small or medium amounts, after breastfeeding was discontinued (OR 5.6; 95% CI, 3.1-10; P<0.001).

    CONCLUSION: This study suggests that having repeated infectious episodes early in life increases the risk for later celiac disease. In addition, we found a synergistic effect between early infections and daily amount of gluten intake, more pronounced among infants for whom breastfeeding had been discontinued prior to gluten introduction. Regarding contribution to the Swedish celiac disease epidemic, which partly was attributed to concurrent changes in infant feeding, early infections probably made a minor contribution via the synergistic effect with gluten amount.

  • 40. Nap, M
    et al.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Börmer, O
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Wagener, C
    Handt, S
    Schreyer, M
    Mach, J P
    Buchegger, F
    von Kleist, S
    Specificity and affinity of monoclonal antibodies against carcinoembryonic antigen.1992In: Cancer Research, ISSN 0008-5472, E-ISSN 1538-7445, Vol. 52, no 8, p. 2329-39Article in journal (Refereed)
    Abstract [en]

    The binding specificities of 52 well-characterized monoclonal antibodies (Mabs) against carcinoembryonic antigen (CEA) from 12 different research groups were studied by immunohistochemistry and immuno flow cytometry. In addition, the binding constant for the interaction between Mab and CEA was determined by a solution-phase assay. Cryostat sections of colon carcinoma and normal colon, stomach, liver, pancreas, and spleen were studied by immunohistochemistry. Peripheral blood granulocytes, monocytes, and lymphocytes were assayed by immuno flow cytometry. The Mabs used here have previously been classified into five essentially nonoverlapping epitope groups (GOLD 1-5) (Cancer Res., 49: 4852-4858, 1989). Most Mabs cross-reacted with different normal tissues, ranging from highly cross-reactive Mabs (positive reaction with 8 of 9 discriminating tissues) to relatively specific Mabs (positive reaction with 1 of 9 discriminating tissues). Five Mabs (10%) were specific, reacting only with colon carcinoma, normal colon mucosa, and normal gastric foveola. There was a correlation between epitope group and binding specificity. Mabs with a high degree of CEA specificity almost exclusively belonged to epitope groups 1, 2, and 3, while highly cross-reactive Mabs belonged to epitope groups 4 and 5. There was no correlation between antibody specificity and affinity for CEA. Specific Mabs with high as well as low affinity were found.

  • 41. Ohlsson, L
    et al.
    Israelsson, A
    Öberg, Å
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Lindmark, G
    Colon cancer: Detection of tumour cells in lymph nodes of colon cancer patients using real-time quantitative reverse transcriptase-polymerase chain reaction (qRT- PCR).2009In: Methods of Cancer Diagnosis, Therapy and Prognosis: Vol. 4: Colorectal Cancer / [ed] M. A. Hayat, Springer, 2009, p. 257-268Chapter in book (Refereed)
  • 42.
    Ohlsson, Lina
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Israelsson, Anne
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Näslund, L.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Öberg, Å.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Lindmark, G.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Biomarker selection for detection of occult tumour cells in lymph nodes of colorectal cancer patients using real-time quantitative RT-PCR2006In: British Journal of Cancer, ISSN 0007-0920, E-ISSN 1532-1827, Vol. 95, no 2, p. 218-225Article in journal (Refereed)
    Abstract [en]

    Accurate identification of lymph node involvement is critical for successful treatment of patients with colorectal carcinoma (CRC). Real-time quantitative RT–PCR with a specific probe and RNA copy standard for biomarker mRNA has proven very powerful for detection of disseminated tumour cells. Which properties of biomarker mRNAs are important for identification of disseminated CRC cells? Seven biomarker candidates, CEA, CEACAM1-S/L, CEACAM6, CEACAM7-1/2, MUC2, MMP7 and CK20, were compared in a test-set of lymph nodes from 51 CRC patients (Dukes' A–D) and 10 controls. Normal colon epithelial cells, primary tumours, and different immune cells were also analysed. The biomarkers were ranked according to: (1) detection of haematoxylin/eosin positive nodes, (2) detection of Dukes' A and B patients, who developed metastases during a 54 months follow-up period and (3) identification of patients with Dukes' C and D tumours using the highest value of control nodes as cutoff. The following properties appear to be of importance; (a) no expression in immune cells, (b) relatively high and constant expression in tumour tissue irrespective of Dukes' stage and (c) no or weak downregulation in tumours compared to normal tissue. CEA fulfilled these criteria best, followed by CK20 and MUC2.

  • 43.
    Ohlsson, Lina
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Lindmark, Gudrun
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Sitohy, Basel
    Umeå University, Faculty of Medicine, Department of Radiation Sciences, Oncology.
    Ectopic expression of the chemokine CXCL17 in colon cancer cells2016In: British Journal of Cancer, ISSN 0007-0920, E-ISSN 1532-1827, Vol. 114, no 6, p. 697-703Article in journal (Refereed)
    Abstract [en]

    Background: The novel chemokine CXCL17 acts as chemoattractant for monocytes, macrophages and dendritic cells. CXCL17 also has a role in angiogenesis of importance for tumour development. Methods: Expression of CXCL17, CXCL10, CXCL9 and CCL2 was assessed in primary colon cancer tumours, colon carcinoma cell lines and normal colon tissue at mRNA and protein levels by real-time qRT-PCR, immunohistochemistry, two-colour immunofluorescence and immunomorphometry. Results: CXCL17 mRNA was expressed at 8000 times higher levels in primary tumours than in normal colon (P<0.0001). CXCL17 protein was seen in 17.2% of cells in tumours as compared with 0.07% in normal colon (P = 0.0002). CXCL10, CXCL9 and CCL2 mRNAs were elevated in tumours but did not reach the levels of CXCL17. CXCL17 and CCL2 mRNA levels were significantly correlated in tumours. Concordant with the mRNA results, CXCL10-and CXCL9-positive cells were detected in tumour tissue, but at significantly lower numbers than CXCL17. Two-colour immunofluorescence and single-colour staining of consecutive sections for CXCL17 and the epithelial cell markers carcinoembryonic antigen and BerEP4 demonstrated that colon carcinoma tumour cells indeed expressed CXCL17. Conclusions: CXCL17 is ectopically expressed in primary colon cancer tumours. As CXCL17 enhances angiogenesis and attracts immune cells, its expression could be informative for prognosis in colon cancer patients.

  • 44.
    Ohlsson, Lina
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Öberg, Åke
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Lindmark, Gudrun
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Pro-inflammatory and down-regulatory cytokine expression in tumor infiltrated mesenteric lymph nodes of patients with colorectal cancerManuscript (preprint) (Other academic)
  • 45.
    Ohlsson, Lina
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Israelsson, Anne
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Öberg, Åke
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Lindmark, Gudrun
    Department of Surgery, Helsingborgs Lasarett, Lund University, Helsingborg, Sweden.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Detection of Tumor Cells in Lymph Nodes of Colon Cancer Patients Using Real-Time Quantitative Reverse Transcription-Polymerase Chain Reaction2009In: Colorectal Cancer / [ed] M. A. Hayat, NEW YORK: Springer Netherlands, 2009, Vol. 4, p. 257-268Chapter in book (Other academic)
    Abstract [en]

    Colorectal cancer is ranked third in worldwide incidence for women and fourth for men representing ͌ 9% of the world cancer or approximately 1 million new cases for 2002 (Parkin et al., 2005). Two thirds of colorectal cancers are located in the colon and one third in the rectum. At diagnosis approximately one third of all patients with colorectal cancer has lymph node positive disease, one third has lymph node-negative disease, and one third has distant metas-tases (Benson et al., 2004). The principal curative treatment for colorectal cancer is surgery. Adjuvant chemotherapy given to lymph node positive colon cancer patients has been shown to increase the survival rate (Haydon, 2003). In rectal cancer patients preoperative irradiation therapy is given to reduce local recurrences and has also been shown to improve survival (Folkesson et al., 2005). Still with these improved treatment modalities only approximately half the number of patients will survive for 5 years. For example, Swedish results for the time period 1995–1999 show a 5-years relative survival of ≈ 57% for both genders (Birgisson et al., 2005).

    Tumor stage, based on histopathologi-cal examination of the resected specimen, and perioperative findings predict survival. Relative 5-year survival in Dukes' A (T1-2N0M0, Stage I) is 90–95%, Dukes' B (T3-4N0M0, Stage II) 60–80%, Dukes' C (anyTN1-2M0, Stage III) 40–60% and Dukes' D (anyTN0-2M1, Stage IV) < 5% (Staib et al., 2002). Besides distant metas-tases the most important prognostic indicator is the status of the regional lymphatic field showing presence or absence of tumor cells in regional lymph nodes. Given the importance of correctly identifying Dukes' C patients, i.e., patients with lymph node involvement who are eligible for chemotherapy, we have focused on improving the methods for detecting disseminated tumor cells in regional lymph nodes.

  • 46.
    Ohlsson, Lina
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Israelsson, Anne
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Öberg, Åke
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Palmqvist, Richard
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Pathology.
    Stenlund, Hans
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Epidemiology and Global Health.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Lindmark, Gudrun
    Lymph node CEA and MUC2 mRNA as useful predictors of outcome in colorectal cancer2012In: International Journal of Cancer, ISSN 0020-7136, E-ISSN 1097-0215, Vol. 130, no 8, p. 1833-1843Article in journal (Refereed)
    Abstract [en]

    The aim was to explore the utility for staging and prognostic impact of carcinoembryonic antigen (CEA), cytokeratin 20 (CK20), guanylyl cyclase C (GCC), CUB domain protein 1 (CDCP1) and mucin 2 (MUC2) mRNA levels in mesenteric lymph nodes of colorectal cancer (CRC) patients. Lymph nodes were collected at surgery and bisected; one half was subjected to biomarker mRNA analysis using real-time quantitative RT-PCR and the other half to routine histopathology. Lymph nodes from 174 CRC patients and 24 controls were analyzed. The median follow-up time was 59 (range 17-131) months. Cut-off levels were defined by analyzing quintiles by Cox regression model. CEA mRNA showed the best discriminating power between patients with recurrence in CRC after surgery and patients who were apparently disease-free (P=0.015). The risk of recurrence for the CEA(+) patients was 4.6 times greater than for the CEA(-) patients (P<0.0001). The other biomarkers gave lower hazard ratios. Cumulative survival analysis demonstrated that the average survival time was 99 months for CEA(-) patients compared to 39 months for CEA(+) patients, a difference of 60 months (P<0.0001). Six to nine percent of the stage I and II patients [H&E(-)] had CEA(+), CK20(+), GCC(+) and/or MUC2(+) lymph nodes. Two of these patients died from recurrent CRC. Low lymph node MUC2/CEA mRNA ratio identified patients with high risk for recurrence (P=0.011). Thus, qRT-PCR of CEA mRNA is a sensitive method to identify tumor cells in lymph nodes of CRC patients and, in combination with MUC2 mRNA, allows improved prediction of clinical outcome. © 2011 Wiley-Liss, Inc.

  • 47.
    Ohlsson, Lina
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Lindmark, G
    Israelsson, Anne
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Palmqvist, Richard
    Umeå University, Faculty of Medicine, Department of Medical Biosciences.
    Öberg, Åke
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Lymph node tissue kallikrein-related peptidase 6 mRNA: a progression marker for colorectal cancer.2012In: British Journal of Cancer, ISSN 0007-0920, E-ISSN 1532-1827, Vol. 107, no 1, p. 150-157Article in journal (Refereed)
    Abstract [en]

    Background:A most important characteristic feature for poor prognosis in colorectal cancer (CRC) is the presence of lymph node metastasis. Determination of carcinoembryonic antigen (CEA) mRNA levels in lymph nodes has proven powerful for quantification of disseminated tumour cells. Here, we investigate the utility of human tissue kallikrein-related peptidase 6 (KLK6) mRNA as a progression biomarker to complement CEA mRNA, for improved selection of patients in need of adjuvant therapy and intensified follow-up after surgery.Methods:Lymph nodes of pTNM stage I-IV CRC- (166 patients/503 lymph nodes) and control (23/108) patients were collected at surgery and analysed by quantitative RT-PCR.Results:Lymph node KLK6 positivity was an indicator of poor outcome (hazard ratio 3.7). Risk of recurrence and cancer death increased with KLK6 lymph node levels. Patients with KLK6 lymph node levels above the 90th percentile had a hazard ratio of 6.5 and 76 months shorter average survival time compared to patients with KLK6 negative nodes. The KLK6 positivity in lymph nodes with few tumour cells, that is, low CEA mRNA levels, also indicated poor prognosis (hazard ratio 2.8).Conclusion:In CRC patients, lymph node KLK6 positivity indicated presence of aggressive tumour cells associated with poor prognosis and high risk of tumour recurrence.

  • 48.
    Ohlsson, Lina
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Lindmark, Gudrun
    Israelsson, Anne
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Palmqvist, Richard
    Umeå University, Faculty of Medicine, Department of Medical Biosciences, Pathology.
    Öberg, Åke
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Hammarström, Sten
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology.
    Lymph node kallicrein 6 mRNA: a new progression marker for colorectal cancerArticle in journal (Other academic)
  • 49. Olofsson, Katarina
    et al.
    Hellström, S
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Otorhinolaryngology.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Abundance of intraepithelial gamma delta T cells in hypertrophic obstructive but not in chronically infected adenoids1996In: Clinical and Experimental Immunology, ISSN 0009-9104, E-ISSN 1365-2249, Vol. 106, no 2, p. 396-403Article in journal (Refereed)
    Abstract [en]

    Using quantitative morphometric analysis of immunohistochemically stained tissue sections we compared hypertrophic obstructive adenoids (HOA, n = 10) from children without middle ear disease with chronically infected adenoids (CIA, n = 10) from children with middle ear disease. gamma delta T cell receptor (TCR)+ cells constituted the dominating T cell population in the surface epithelium of HOA, while alpha beta TCR+ cells were the dominating intraepithelial T cell population in CIA. Intraepithelially CD8+ cells dominated over CD4+ cells in both diseases. Intraepithelially B cells were not detected. The cellular composition of follicles, with B cells dominating followed by activated CD4+ alpha beta TCR+ cells, was the same in both groups. However, the number of follicles in CIA was twice as many as in HOA. In the deeper interfollicular areas granulocytes were more abundant in CIA than in HOA. The latter two findings suggest a more pronounced inflammatory response in the adenoids of patients with middle ear disease. There was no significant difference with regard to pathogenic bacterial strains colonizing the adenoid surface when comparing the two patient groups. These results suggest that in patients with HOA gamma delta TCR+ T cells help to maintain the integrity of the surface epithelium, thereby preserving its protective function. On the basis of our results we speculate that CIA have a malfunctioning defence, thereby facilitating long-standing infections deep in the adenoid. This may be the main reason for development of middle ear disease and an indication for adenoidectomy in patients with CIA.

  • 50.
    Olofsson, Katarina
    et al.
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Otorhinolaryngology.
    Hellström, S
    Umeå University, Faculty of Medicine, Department of Clinical Sciences, Otorhinolaryngology.
    Hammarström, Marie-Louise
    Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Immunology/Immunchemistry.
    Human uvula: characterization of resident leukocytes and local cytokine production2000In: Annals of Otology, Rhinology and Laryngology, ISSN 0003-4894, E-ISSN 1943-572X, Vol. 109, no 5, p. 488-496Article in journal (Refereed)
    Abstract [en]

    Upper airway infections often lead to macroscopic changes in the architecture of the uvula. Using immunomorphometric analysis, we investigated the frequency and distribution of immune cells and of cytokine-producing cells in uvular samples. Tissue macrophages, alphabeta T cells, gammadelta T cells, and B cells were, in declining order, the main cell populations. Gammadelta T cells and B cells exhibited reciprocal localization, with almost all gammadelta T cells residing in the vicinity of the epithelium, and all B cells in the glandular area. The presence of cells expressing the suppressor phenotype CD8+CD28- alphabeta T cells is suggested. Fifteen to twenty-five percent of the immune cells expressed the down-regulatory cytokine tumor growth factor beta. Most macrophages were located subepithelially, in the vicinity of the basal lamina. The composition and cytokine profile of leukocytes in the tissue suggest that the uvula may be a site, additional to the jejunal mucosa, for induction of mucosal tolerance to inhaled and ingested antigens. Concomitantly, the uvula appears to be protected from invasion of microbial pathogens by a subepithelial barrier of macrophages and gammadelta T cells.

12 1 - 50 of 88
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