title: Characterization of the T cells in aged rat bone marrow.
abstract: In this study, we determined the characteristics of CD3-positive (CD3+) T cells existing in rat bone marrow (BM). In contrast to splenic T cells, BM CD3+ T cells are composed of a higher proportion of CD8+ T cells, and the number of both cell types increased with age. Such CD3+ T cells in aged rats showed a similar usage of TCR V beta as splenic T cells, suggesting that BM CD3+ T cells are thymus-dependent and composed of an ordinary population in view of the expression of the TCR beta-chain. Purified T cells obtained from aged rat BM showed a markedly proliferative response by stimulation with immobilized anti-CD3 mAb, as did splenic T cells. However, the addition of BM non-T cells completely inhibited the response of both BM and splenic T cells in vitro. These results suggest that T cells in rat BM are negatively regulated by BM non-T cells in their response to the TCR-mediated signal not to disrupt the microenvironment of the BM.
authors.affiliation: Department of Immunology, Tokai University School of Medicine, Isehara, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Hozumi
authors.forename: T
authors.initials: T
authors.lastname: Masuko
authors.forename: T
authors.initials: T
authors.lastname: Nishimura
authors.forename: S
authors.initials: S
authors.lastname: Habu
authors.forename: Y
authors.initials: Y
authors.lastname: Hashimoto
mesh_terms: D000375:Aging / Q000276:immunology*; D000818:Animals; D001853:Bone Marrow / Q000276:immunology; D001854:Bone Marrow Cells; D017252:CD3 Complex / Q000032:analysis*; D016516:CD4-CD8 Ratio; D015496:CD4-Positive T-Lymphocytes; D016827:CD8 Antigens / Q000032:analysis; D002455:Cell Division; D002478:Cells, Cultured; D005434:Flow Cytometry; D007153:Immunologic Deficiency Syndromes / Q000235:genetics / Q000276:immunology / Q000473:pathology; D008213:Lymphocyte Activation; D008297:Male; D016853:Muromonab-CD3 / Q000494:pharmacology; D051381:Rats; D011916:Rats, Inbred F344 / Q000276:immunology; D011923:Rats, Nude / Q000276:immunology; D017260:Receptor-CD3 Complex, Antigen, T-Cell / Q000032:analysis; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000032:analysis; D016176:T-Lymphocyte Subsets / Q000276:immunology
chemical_list: D017252:CD3 Complex; D016827:CD8 Antigens; D016853:Muromonab-CD3; D017260:Receptor-CD3 Complex, Antigen, T-Cell; D016693:Receptors, Antigen, T-Cell, alpha-beta