title: Expression of Ly-6 alloantigen during differentiation of cytotoxic T cells.
abstract: We have prepared anti-Ly-6.2 by immunization of (CBA/Ca X A-Thy-1a)F1 with AKR/Crc lymphocytes and used the antiserum to study heterogencity of peripheral T lymphocytes. The Ly-6 alloantigen is found on all activated cytotoxic T cells studied, directed to a variety of different target antigens. The antiserum reveals heterogeneity among the precursors of T killer cells, i.e. allogeneic precursors are Ly-6-, whereas the generation of cytotoxic cells to hapten-modified syngeneic cells and xenogeneic cells is partially abrogated by serum pretreatment. Precursors of some in vivo primed responses are also Ly-6+. These findings indicate that the expression of Ly-6 antigen is, at least, partially related to the stage of T cell activation. The in vitro proliferative response of T cells to allogeneic Ia antigens is substantially reduced by pretreatment with anti-Ly-6.2 serum suggesting that this antiserum may be a useful tool for the study of heterogeneity in the Ly-1+ pool of T cells.
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D003602:Cytotoxicity, Immunologic; D007518:Isoantibodies / Q000008:administration & dosage; D007519:Isoantigens; D007694:Killer Cells, Natural / Q000276:immunology; D008213:Lymphocyte Activation; D008211:Lymphocyte Cooperation; D007959:Lymphocyte Culture Test, Mixed; D051379:Mice; D008815:Mice, Inbred Strains; D010641:Phenotype; D051381:Rats; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D007518:Isoantibodies; D007519:Isoantigens