PT  - JOURNAL ARTICLE
AU  - Hörnquist, C E
AU  - Lu, X
AU  - Rogers-Fani, P M
AU  - Rudolph, U
AU  - Shappell, S
AU  - Birnbaumer, L
AU  - Harriman, G R
TI  - G(alpha)i2-deficient mice with colitis exhibit a local increase in memory CD4+ T cells and proinflammatory Th1-type cytokines.
DP  - 1997 Feb 01
TA  - The Journal of Immunology
PG  - 1068--1077
VI  - 158
IP  - 3
4099  - http://www.jimmunol.org/content/158/3/1068.short
4100  - http://www.jimmunol.org/content/158/3/1068.full
SO  - J. Immunol.1997 Feb 01; 158
AB  - 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.