The T-cell receptor gamma chain-CD3 complex: implication in the cytotoxic activity of a CD3+ CD4- CD8- human natural killer clone.
A subset of human T cells has recently been described. These cells express the CD3 complex but they do not carry the classical T-cell receptor (TCR)-alpha/-beta heterodimer on their surface (WT31- CD3+). Instead, they express a TCR-gamma chain associated with another type of polypeptide termed TCR-delta. We report here that a T-cell clone with natural killer (NK)-like activity, WM-14, had a disulfide bridged TCR-gamma homodimer associated with CD3 on its surface. The TCR-gamma chains of WM-14 cells were present in three different glycosylation forms of 43, 40, and 38 kDa, but they appeared to contain the same polypeptide backbone. Since cytotoxicity by WM-14 could be inhibited by anti-CD3 antibodies, we concluded that the TCR-gamma-CD3 complex was involved in the NK-like unrestricted killer activity. Although normal CD3-gamma, CD3-delta, and CD3-epsilon chains were present in this clone, the association with the TCR-gamma homodimer may be the cause of a complete processing of the N-linked oligosaccharides attached to the CD3-delta chain.
D000911:Antibodies, Monoclonal; D000945:Antigens, Differentiation, T-Lymphocyte; D000954:Antigens, Surface / Q000235:genetics / Q000276:immunology*; D002460:Cell Line; D002999:Clone Cells; D003602:Cytotoxicity, Immunologic; D006026:Glycoside Hydrolases; D006801:Humans; D007694:Killer Cells, Natural / Q000276:immunology*; D046911:Macromolecular Substances; D011948:Receptors, Antigen, T-Cell / Q000235:genetics / Q000276:immunology*
D000911:Antibodies, Monoclonal; D000945:Antigens, Differentiation, T-Lymphocyte; D000954:Antigens, Surface; D046911:Macromolecular Substances; D011948:Receptors, Antigen, T-Cell; D006026:Glycoside Hydrolases