In situ expression of interleukin-10 in noninflamed human gut and in inflammatory bowel disease.
A dysregulated secretion of contra-inflammatory cytokines such as interleukin-10 (IL-10) could play a role in the pathogenesis of inflammatory bowel disease (IBD). We have investigated the expression of IL-10 in gut tissues from patients with Crohn's disease (CD), ulcerative colitis (UC) and controls by mRNA in situ hybridization and immunohistochemistry. Intestinal epithelial cells were found to express IL-10 mRNA and IL-10 protein in all of the tissues investigated without any major differences in the expression patterns. However, compared with noninflamed gut, significantly increased numbers of mononuclear cells (MNCs) producing IL-10 were present in inflamed gut, both in CD and UC. This cytokine was expressed most prominently by inflammatory infiltrates enriched in macrophages, although T cells seem to contribute to its production as well. Elevated IL-10 expression in IBD was mainly detected in the submucosa, whereas IL-10 production by lamina propria cells remained comparably low. In contrast, the expression of IL-1beta mRNA was preferentially increased in the lamina propria. Our data argue against a general deficiency in IL-10 production in IBD. The results suggest rather that the local production of IL-10 by mucosal MNCs in IBD is insufficient to down-regulate pro-inflammatory cytokines such as IL-1beta in the lamina propria compartment.
Autschbach
F
F
Institute of Pathology, German Cancer Research Center, Heidelberg.
Braunstein
J
J
Helmke
B
B
Zuna
I
I
Schürmann
G
G
Niemir
Z I
ZI
Wallich
R
R
Otto
H F
HF
Meuer
S C
SC
D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D017403:In Situ Hybridization; D015212:Inflammatory Bowel Diseases / Q000276:immunology*; D007375:Interleukin-1 / Q000378:metabolism; D016753:Interleukin-10 / Q000378:metabolism*; D007410:Intestinal Diseases / Q000276:immunology; D007422:Intestines / Q000276:immunology*; D007963:Leukocytes, Mononuclear / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D012333:RNA, Messenger / Q000032:analysis
D007375:Interleukin-1; D012333:RNA, Messenger; D016753:Interleukin-10