title: MHC-unrestricted cytotoxic and proliferative responses of two distinct human gamma/delta T cell subsets to Daudi cells.
abstract: Human V gamma 9/V delta 2 T cells, the major subset of gamma/delta T cells in peripheral blood of adults, mediate proliferative and cytotoxic responses to Daudi Burkitt's lymphoma cells without previous in vitro exposure to Daudi. Our experiments show that some gamma/delta T cells coexpressing V gamma 9 and V delta 1 genes also react to Daudi cells in cytotoxic and proliferative assays. Expression of V gamma 9 is not sufficient for the recognition of Daudi cells because most gamma/delta T cells expressing V delta 1 paired with V gamma 9 or other V gamma genes neither kill Daudi cells nor proliferate to Daudi. V gamma 9/V delta 2 T cells do not proliferate to other cell lines such as K562 or Molt4 that are sensitive to MHC-unrestricted cytolysis by NK cells and by most IL-2-activated gamma/delta T cell clones. Cold target inhibition assays demonstrate that Daudi cells are stronger inhibitors than K562 and Molt4 of MHC-unrestricted lysis by V gamma 9/V delta 2 clones. However, cold Daudi cells are relatively weaker inhibitors of MHC-unrestricted lysis by NK cell clones, most gamma/delta T cell clones expressing V delta 1 and alpha/beta T cell clones. Thus, recognition by V gamma 9/V delta 2 T cells and certain V gamma 9/V delta 1 T cells of Daudi appears to involve a specific triggering pathway that is distinct from recognition by these gamma/delta T cells of Molt4, K562, and other target cells. NK cell clones and most other gamma/delta and alpha/beta T cell clones derived from the same normal volunteer blood donors do not show this specific interaction with Daudi cells. These data show that distinct subsets of human gamma/delta T cells recognize Daudi cells and support the idea that the gamma/delta TCR may be directly involved.
authors.affiliation: Department of Human Oncology, University of Wisconsin, Madison 53792.
authors.forename: P
authors.initials: P
authors.lastname: Fisch
authors.forename: K
authors.initials: K
authors.lastname: Oettel
authors.forename: N
authors.initials: N
authors.lastname: Fudim
authors.forename: J E
authors.initials: JE
authors.lastname: Surfus
authors.forename: M
authors.initials: M
authors.lastname: Malkovsky
authors.forename: P M
authors.initials: PM
authors.lastname: Sondel
mesh_terms: D000942:Antigens, Bacterial / Q000276:immunology; D002051:Burkitt Lymphoma / Q000276:immunology*; D002478:Cells, Cultured; D003602:Cytotoxicity, Immunologic; D006801:Humans; D007694:Killer Cells, Natural / Q000276:immunology; D008213:Lymphocyte Activation; D008285:Major Histocompatibility Complex / Q000276:immunology*; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000032:analysis*; D016176:T-Lymphocyte Subsets / Q000276:immunology*
chemical_list: D000942:Antigens, Bacterial; D016692:Receptors, Antigen, T-Cell, gamma-delta