L. Puddington et al., INTERACTIONS BETWEEN STEM-CELL FACTOR AND C-KIT ARE REQUIRED FOR INTESTINAL IMMUNE-SYSTEM HOMEOSTASIS, Immunity, 1(9), 1994, pp. 733-739
Interactions between stem cell factor (SCF) and its receptor, c-Kit, a
re important for development of hematopoietic, melanocytes, and germ c
ells. T lymphocytes appeared normal in c-Kit (W/W-v) or SCF (SI/SId) m
utant mice, except for those residing within the intestinal epithelium
, the intraepithelial lymphocytes (IEL). Normally, IEL are composed of
equal numbers of cells with alpha beta or gamma delta T cell receptor
s. In mutant mice, beginning at 6-8 weeks of age, the number of gamma
delta IEL decreased, whereas alpha beta IEL increased. The latter was
due largely to an increased CD4(+)CD8(+) TCR alpha beta subset, sugges
ting that these cells may be intermediates in the alpha beta IEL linea
ge. c-Kit or SCF was expressed by IEL or intestinal epithelial cells,
respectively, indicating a potential for direct intercellular interact
ion. This possibility was supported by reconstitution studies that dem
onstrated that c-Kit mutations directly affected IEL. Thus, SCF-c-Kit
interactions are important for homeostasis of the intestinal immune co
mpartment.