title: Bcl-2 expression in the thymus and periphery.
abstract: Bcl-2 proto-oncogene is expressed in normal lymphoid tissues and its role has been suggested to involve the selection of B and T cells. Here we report three-color flow cytometric studies on the expression of bcl-2 protein in the thymus and periphery. Bcl-2 was expressed in the majority of T and B cells and down-regulated only in the CD1+, CD3- to low, CD4+8+ thymocytes, and the B cells that are in cell cycle in the tonsil and lymph node. In contrast, the CD2+, CD1-3-4-8-19-, early T cells, and mature single positive cells in the thymus, as well as the tonsilar and lymph node T cells, irrespective of their cell cycle status, expressed bcl-2. These results are consistent with the notion that bcl-2 is down-regulated in the T and B cells that are in the process of generating new antigen receptors and subject to subsequent positive selection.
authors.affiliation: First Department of Surgery, Osaka University Medical School, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Fujii
authors.forename: M
authors.initials: M
authors.lastname: Okumura
authors.forename: Y
authors.initials: Y
authors.lastname: Takeuchi
authors.forename: K
authors.initials: K
authors.lastname: Inada
authors.forename: K
authors.initials: K
authors.lastname: Nakahara
authors.forename: H
authors.initials: H
authors.lastname: Matsuda
authors.forename: Y
authors.initials: Y
authors.lastname: Tsujimoto
mesh_terms: D000328:Adult; D000368:Aged; D015703:Antigens, CD / Q000032:analysis; D016175:B-Lymphocyte Subsets / Q000378:metabolism; D002454:Cell Differentiation; D002648:Child; D002675:Child, Preschool; D015536:Down-Regulation; D005434:Flow Cytometry; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008198:Lymph Nodes / Q000254:growth & development / Q000276:immunology / Q000378:metabolism; D008214:Lymphocytes / Q000276:immunology*; D008221:Lymphoid Tissue / Q000276:immunology / Q000378:metabolism*; D008875:Middle Aged; D014066:Palatine Tonsil / Q000254:growth & development / Q000276:immunology / Q000378:metabolism; D000090063:Proto-Oncogene Mas; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis*; D019253:Proto-Oncogene Proteins c-bcl-2; D016176:T-Lymphocyte Subsets / Q000378:metabolism; D013950:Thymus Gland / Q000254:growth & development / Q000276:immunology / Q000378:metabolism*
chemical_list: D015703:Antigens, CD; C000715470:MAS1 protein, human; D000090063:Proto-Oncogene Mas; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2