title: Qa-2 expression in the adult murine thymus. A unique marker for a mature thymic subset.
abstract: The MHC Ag, Qa-2, is expressed on all peripheral T cells, a subset of bone marrow cells, and to a lesser extent on B cells. The Qa-2 Ag is also expressed on 5 to 6% of normal adult murine thymocytes. Through the use of flow cytometry, counterflow centrifugal elutriation and acridine orange staining, we have analyzed the cell surface phenotype, cell size, and cell cycle status of this thymic population. Our studies indicate that Qa-2+ thymocytes are large, non-mitotic, G1 cells which have the cell surface phenotype of CD5+, CD3+, J11dLO and lack receptors for peanut agglutinin. This population can be further subdivided into three categories; CD4+/CD8-, CD4-/CD8+, and CD4-/CD8-. These data indicate that Qa-2 surface expression can only be detected on thymocytes in the final stages of differentiation. The Qa-2 Ag can be used as a cell surface marker to identify a unique subset of mature thymocytes.
authors.affiliation: Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205.
authors.forename: J
authors.initials: J
authors.lastname: Vernachio
authors.forename: M
authors.initials: M
authors.lastname: Li
authors.forename: A D
authors.initials: AD
authors.lastname: Donnenberg
authors.forename: M J
authors.initials: MJ
authors.lastname: Soloski
mesh_terms: D000818:Animals; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis; D000954:Antigens, Surface / Q000032:analysis; D015815:Cell Adhesion Molecules; D002453:Cell Cycle; D002454:Cell Differentiation; D002469:Cell Separation; D015395:Histocompatibility Antigens Class I / Q000032:analysis*; D037102:Lectins; D007958:Leukocyte Count; D051379:Mice; D008810:Mice, Inbred C57BL; D019887:Peanut Agglutinin; D011948:Receptors, Antigen, T-Cell / Q000032:analysis; D011971:Receptors, Immunologic / Q000032:analysis; D016201:Receptors, Lymphocyte Homing; D013601:T-Lymphocytes / Q000145:classification* / Q000502:physiology
chemical_list: D000945:Antigens, Differentiation, T-Lymphocyte; D000954:Antigens, Surface; D015815:Cell Adhesion Molecules; D015395:Histocompatibility Antigens Class I; D037102:Lectins; D019887:Peanut Agglutinin; C032907:Q surface antigens; D011948:Receptors, Antigen, T-Cell; D011971:Receptors, Immunologic; D016201:Receptors, Lymphocyte Homing