Cytolytic activity of intestinal intraepithelial lymphocytes in germ-free mice is strain dependent and determined by T cells expressing gamma delta T-cell antigen receptors.
We have compared the cytolytic activities and the cellular compositions of the intestinal intraepithelial lymphocyte (i-IEL) populations in three different combinations of conventional (CV) and germ-free (GF) mice. Cytolytic activity of i-IELs expressing gamma delta T-cell antigen receptors (TCRs) is strain dependent in CV mice (high vs. low), and this strain-dependent variability is unaltered in the GF condition. Although absolute numbers of gamma delta i-IELs are slightly decreased, the composition of CD8 alpha alpha+ and CD4-CD8- subsets and the usage of TCR gamma- and delta-chain variable gene segments by gamma delta i-IELs remain the same in GF mice. By contrast, cytolytic activity of alpha beta TCR-expressing i-IELs is uniformly high in CV mice but attenuated sharply in the GF condition. A conspicuous decrease in the total numbers of alpha beta i-IELs is also noted, and CD8 alpha beta+ and CD4+CD8+ subsets are reduced, whereas the CD8 alpha alpha+ subset is expanded in GF mice. These results indicate that microbial deprivation preferentially influences the alpha beta i-IEL population to decrease and become noncytolytic but has little effect on the pool size or characteristics of gamma delta i-IELs. Consequently, cytolytic activity of freshly isolated i-IELs from GF mice is determined by T cells expressing gamma delta TCRs and is found to be strain dependent.
Yakult Central Institute for Microbiological Research, Tokyo, Japan.
M
M
Kawaguchi
M
M
Nanno
Y
Y
Umesaki
S
S
Matsumoto
Y
Y
Okada
Z
Z
Cai
T
T
Shimamura
Y
Y
Matsuoka
M
M
Ohwaki
H
H
Ishikawa
D000818:Animals; D000911:Antibodies, Monoclonal; D017252:CD3 Complex / Q000276:immunology; D002478:Cells, Cultured; D003602:Cytotoxicity, Immunologic; D004848:Epithelium; D005455:Fluorescent Antibody Technique; D007422:Intestines / Q000166:cytology / Q000276:immunology*; D007700:Kinetics; D012515:Mast-Cell Sarcoma; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008815:Mice, Inbred Strains; D010641:Phenotype; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000032:analysis / Q000096:biosynthesis / Q000235:genetics; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000032:analysis / Q000096:biosynthesis* / Q000235:genetics; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*; D014407:Tumor Cells, Cultured
D000911:Antibodies, Monoclonal; D017252:CD3 Complex; D016693:Receptors, Antigen, T-Cell, alpha-beta; D016692:Receptors, Antigen, T-Cell, gamma-delta