Development and physiological role of gammadelta T cells.

点击翻译按钮获取中文摘要

Although T-cells bearing gammadelta T-cell receptors have long been known to be present in the epithelial lining of many organs, their development, specificity and function remain elusive. In this study, we analyzed the physiological significance of one major gammadelta T-cell subset which is localized in the mouse intestinal epithelium. The pool of intestinal intraepithelial T-cells (IEL) of adult mice is comparable in size to the T-cell pool in the spleen. It consists of both alphabeta T-cells (40-70%) and gammadelta T-cells (30-60%).Our result show ;1)Microbial deprivation in germ-free mice preferentially influences the alphabeta-IEL population to decrease and become noncytolytic but has little effect on the pool size or characteristics of gammadelta-IEL.2)Colonization of IEL in the aly mutant mice takes place in the complate absence of Peyer^<, >s patches and IgA-producing B cells in lamina propria.3)The absence of gammadelta-IEL is associated with a reduction in intestinal epithelial cell turnover and a downregulation of the expression of MHC class II molecules.These results indicate that alphabeta- and gammadelta-IEL develop independently of Peyer^<, >s patches in the intestinal epithelium and differ from each other in their physiological function at the gut mucosa.