Role of γδT Cells in the Inflammatory Response of Experimental Colitis Mice

Abstract

We examined the severity of experimental colitis induced by dextran sulfate sodium (DSS) using immunologically manipulated mice. C57BL/6 mice showed more severe colitis than BALB/c mice, but mice of both strains recovered fully from the disease after the removal of DSS from their drinking water. The infiltrated cells at the lesions were mainly granulocytes in normal littermates. However, C.B-17 scid, IL-7Rα deficient, and TCR-Cβδ double-deficient mice showed severe colitis and did not recover from the disease even after the removal of DSS. It was found that the infiltrated cells at the lesions in the lethal strains were monocytes. Although both TCR-Cδ−/− and TCR-Cβ−/− mice showed severe colitis phenotypes, infiltration in the former is monocyte-dominant while that in the latter is granulocyte-dominant. Thus the type of cells that infiltrate at the lesions of DSS-induced experimental colitis may be controlled by functional T cell subsets. Immunohistological and RT-PCR analyses of the inflamed colon revealed that the murine homologue of human GROα released by some cells under the control of γδT cells is a possible candidate determining the severity of DSS-induced experimental colitis.

Select Plant Tannins Induce IL-2Rα Up-Regulation and Augment Cell Division in γδ T Cells

“…For instance, Cat's Claw is a traditional South American medicine used to treat a variety of illnesses including allergies, cancer, colitis, dysentery, and urinary tract infection (50). Interestingly, these illnesses are commonly associated with ␥␦ T cell regulatory activities (7,(51)(52)(53)(54), suggesting the described immunostimulatory properties of the Cat's Claw plant could be partially due to the activation of ␥␦ T cells. Preparations containing the apple-condensed tannins we described are also recognized for similar immunostimulatory properties (49,(55)(56)(57).…”

Dextran Sulfate Sodium‐induced Colitis Generates a Transient Thymic Involution – Impact on Thymocyte Subsets

“…This indicates that the intestinal microflora is not necessary for inducing colitis but is likely to play a role in the modulation of the disease. The first cells to infiltrate the mucosa and submucosa after DSS challenge are large numbers of neutrophils and macrophages, followed by T and B lymphocytes [19]. The exact role of T and B cells in the DSS colitis model is still not known as various lymphocyte-deficient animals, such as CD4-depleted mice, nude mice and SCID mice, develop similar or aggravated colitis compared with wildtype mice [20,21] manifested as a higher mortality rate after prolonged exposure to DSS.…”

Regulation of dextran sodium sulfate induced colitis by leukocyte beta 2 integrins

“…60 Early reports dismissed a role for T cells in DSS colitis; however, recent reports suggest that this cell population may participate in a regulatory manner through influencing recruitment of specific leukocyte populations (ie monocytes vs granulocytes) or by providing growth factors necessary for epithelial cell survival and regeneration during DSS colitis. 26,28 Therefore, it is possible that CD11b deficiency may alter T-cell regulatory functions during DSS colitis. While both of these possibilities may be involved, future studies are needed to better understand how CD11b modulates DSS induced colitis.…”

“…24,25 Immunopathogenesis of the DSS model involves multiple immune cell types implicated in human IBD including neutrophils and monocytes, with lymphocytes serving a regulatory role. 22,[25][26][27][28] Therefore, we used the DSS colitis model to determine the pathological role of leukocyte b 2 integrins during experimental colitis. Here, we report that gene targeted null deficiency of CD18 b 2 integrin and CD11a (a L integrin) significantly attenuates the development of DSS-induced colitis, and that loss of CD11b (a M chain) actually enhanced DSS-induced colitis.…”