title: Alterations in CD8+ cell distribution in gut-associated lymphoid tissues (GALT) of the aging Fischer 344 rat: a correlated immunohistochemical and flow cytometric analysis.
abstract: The distribution of CD8+ phenotype (cytotoxic/suppressor) T lymphocytes in Peyer's patches and intestinal lamina propria in young adult (3-6 months) and old (24-29 months) Fischer 344 rats was examined using immunohistochemical and flow cytometric analyses. Flow cytometric analysis confirmed previous reports indicating no change with age in the proportion of Peyer's patch CD8+ cells in the rat. Immunohistochemical analysis showed discrete zones of densely stained CD8+ cells in the interfollicular areas and weakly stained cells within the follicles in Peyer's patches in young adult animals. In old rats, the number of intensely stained CD8+ cells between the follicles was markedly reduced and positively stained cells were distributed throughout the Peyer's patches. In addition, the population density of CD8+ cells is more diffuse in old animals, the number of CD8+ lymphocytes in the intestinal lamina propria increased 2.5-fold with aging from 533 +/- 59 cells/mm2 in young adult to 1312 +/- 83 cells/mm2 in old rats. The findings suggest that CD8+ cell distribution in the inductive and effector sites of gut associated lymphoid tissue undergoes age-related shifts.
authors.affiliation: Department of Pharmaceutical Sciences, College of Pharmacy, Idaho State University, Pocatello.
authors.forename: C K
authors.initials: CK
authors.lastname: Daniels
authors.forename: P
authors.initials: P
authors.lastname: Perez
authors.forename: D L
authors.initials: DL
authors.lastname: Schmucker
mesh_terms: D000375:Aging / Q000276:immunology*; D000818:Animals; D016827:CD8 Antigens / Q000032:analysis*; D005434:Flow Cytometry; D007150:Immunohistochemistry; D007413:Intestinal Mucosa / Q000276:immunology*; D008297:Male; D010581:Peyer's Patches / Q000276:immunology; D051381:Rats; D011916:Rats, Inbred F344; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D016827:CD8 Antigens