title: Human cytotoxic lymphocytes. V. Frequency and specificity of gamma delta+ cytotoxic lymphocyte precursors activated by allogeneic or autologous stimulator cells.
abstract: We have investigated the frequency and specificity of gamma delta+ cytotoxic lymphocyte precursors (CLP) under limiting dilution culture conditions. E rosette separated total T cells and CD3+CD4-CD8-TCR alpha beta- double-negative (DN) T cells were cocultured with allogeneic or autologous PBMC stimulator cells, and frequencies of alloreactive and autoreactive CLP were determined after 12 to 14 days against Con A blast target cells. Freshly isolated DN cells consisting of 82.3 +/- 8.2% gamma delta+ T cells did not exert cytolytic activity against K562 or anti-TCR gamma delta mAb-producing hybridoma cells. In striking contrast to E+ cells, the vast majority of alloantigen-stimulated clonally developing DN CLP did not show specificity for stimulator-derived target cells. Thus, frequencies of alloreactive and autoreactive CLP after alloantigenic stimulation were in the range of 1/100 to 1/4800 and 1/450 to 1/5000, respectively. After coculture with autologous stimulator cells, frequencies of autoreactive and alloreactive DN CLP were 1/700 to 1/2700 and 1/1360 to 1/4500, respectively. Split culture analysis revealed that most proliferating DN colonies selected for high probability of clonality simultaneously killed both autologous and HLA-mismatched allogeneic targets. The majority of the DN cells expressed the CD3+/TCR gamma delta+ phenotype after culture, and thus were not CD2+CD3- NK cells. Taken together, our results show that 1) freshly isolated peripheral blood gamma delta+ T cells lack cytotoxic activity, and 2) most cytotoxic gamma delta+ T cells activated by autologous or allogeneic stimulator cells under limiting dilution conditions do not discriminate between autologous and allogeneic targets.
authors.affiliation: Institute of Immunology, University of Heidelberg, West Germany.
authors.forename: D
authors.initials: D
authors.lastname: Kabelitz
authors.forename: A
authors.initials: A
authors.lastname: Bender
authors.forename: S
authors.initials: S
authors.lastname: Schondelmaier
authors.forename: M L
authors.initials: ML
authors.lastname: da Silva Lobo
authors.forename: O
authors.initials: O
authors.lastname: Janssen
mesh_terms: D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis; D015704:CD4 Antigens / Q000032:analysis; D016827:CD8 Antigens; D002454:Cell Differentiation; D002469:Cell Separation; D003602:Cytotoxicity, Immunologic; D006680:HLA Antigens / Q000276:immunology; D006801:Humans; D008213:Lymphocyte Activation; D011948:Receptors, Antigen, T-Cell / Q000145:classification*; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D013602:T-Lymphocytes, Cytotoxic / Q000166:cytology / Q000276:immunology*
chemical_list: D000945:Antigens, Differentiation, T-Lymphocyte; D015704:CD4 Antigens; D016827:CD8 Antigens; D006680:HLA Antigens; D011948:Receptors, Antigen, T-Cell