title: Age-related changes of T cell subsets in intestinal intraepithelial lymphocytes of mice.
abstract: Age-related changes in T cell subsets were examined in intestinal intraepithelial lymphocytes (i-IEL), which contain unique T cells differentiating extrathymically. In 2-month-old mice bred under conventional condition, i-IEL consisted of a large number of CD4-CD8 alpha/alpha+ cells bearing either T cell receptor (TcR)alpha/beta or TcR gamma/delta and only a few CD4+CD8 alpha- cells. In aged mice (6 months old and 24 months old), unique CD4+CD8 alpha/alpha+ i-IEL bearing TcR alpha/beta increased in number and conversely the proportion of TcR gamma/delta+ i-IEL was decreased. Such an increase in number of CD4+CD8 alpha/alpha+ cells was detected in i-IEL from aged (14-months old) nude mice, but not in aged (14 months old) germ-free mice, suggesting that a significant fraction of TcR alpha/beta T cells such as CD4+CD8 alpha+ i-IEL can develop along an extrathymic pathway under the influence of intestinal microflora with age.
authors.affiliation: Laboratory of Germfree Life, Nagoya University School of Medicine, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Takeuchi
authors.forename: H
authors.initials: H
authors.lastname: Miyazaki
authors.forename: K
authors.initials: K
authors.lastname: Mirokawa
authors.forename: T
authors.initials: T
authors.lastname: Yokokura
authors.forename: Y
authors.initials: Y
authors.lastname: Yoshikai
mesh_terms: D000367:Age Factors; D000818:Animals; D000954:Antigens, Surface / Q000032:analysis; D016516:CD4-CD8 Ratio; D004847:Epithelial Cells; D005260:Female; D005434:Flow Cytometry; D005856:Germ-Free Life; D016130:Immunophenotyping; D007413:Intestinal Mucosa / Q000276:immunology*; D017493:Leukocyte Common Antigens / Q000032:analysis; D008562:Membrane Glycoproteins / Q000032:analysis; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008819:Mice, Nude; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000032:analysis; D016201:Receptors, Lymphocyte Homing / Q000032:analysis; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D018800:Thy-1 Antigens
chemical_list: D000954:Antigens, Surface; D008562:Membrane Glycoproteins; D016693:Receptors, Antigen, T-Cell, alpha-beta; D016201:Receptors, Lymphocyte Homing; D018800:Thy-1 Antigens; D017493:Leukocyte Common Antigens