First Author | Hörnquist CE | Year | 1997 |
Journal | J Immunol | Volume | 158 |
Issue | 3 | Pages | 1068-77 |
PubMed ID | 9013944 | Mgi Jnum | J:38373 |
Mgi Id | MGI:85744 | Doi | 10.4049/jimmunol.158.3.1068 |
Citation | Hornquist CE, et al. (1997) G(alpha)i2-deficient mice with colitis exhibit a local increase in memory CD4+ T cells and proinflammatory Th1-type cytokines. J Immunol 158(3):1068-77 |
abstractText | Mice with targeted deletion of the G protein G(alpha)i2 develop an inflammatory bowel disease closely resembling ulcerative colitis. To better define disease pathogenesis, the mucosal immune system in G(alpha)i2-deficient mice was studied. Phenotypic analysis of large intestine lamina propria lymphocytes revealed a large increase in memory CD4+ T cells (CD44high, CD45RBlow, CD62Llow). Furthermore, expression of the mucosal homing receptor integrin beta7 was increased on mucosal, but not systemic, CD4+ T cells. Analysis of cytokine production revealed a marked increase in proinflammatory Th1-type cytokines in inflamed colons, as compared with wild-type mice or G(alpha)i2-deficient mice without colitis. Thus, IFN-gamma and IL-1beta levels were increased 13-fold and 30-fold, respectively, with more modest increases in IL-6 levels (5-fold) and TNF levels (2-fold). Inflamed colons of G(alpha)i2-deficient mice also demonstrated increased IL-12 p40 mRNA levels. No increase in IL-2, IL-4, IL-5, and IL-10 was seen. Large intestinal epithelial cells in G(alpha)i2-deficient mice with colitis were found by immunohistochemistry to express increased levels of both MHC class I and class II Ags. Colitis was associated with increased IgG levels (60-fold increase), predominantly IgG2a (135-fold increase), in large but not small intestinal secretions. This was shown by ELISPOT analysis to result from local production within the lamina propria. |