title: HLA class I specific T lymphocyte clones with dual alloreactive functions.
abstract: Four human T lymphocyte clones exhibiting proliferative responses to class I HLA antigens were isolated from an in vitro mixed lymphocyte culture (MLC). Three clones expressed the Leu-2+3- phenotype and demonstrated proliferation in response to HLA-B8, while the fourth clone expressed the Leu-2-3+ phenotype and proliferated in response to HLA-A2. These clones were also cytotoxic towards cells bearing the same target antigens. Blocking studies utilizing monoclonal antibodies demonstrated that proliferation was triggered by determinants on the class I molecule itself, and these determinants appear to be spatially close to those which determine serologic allospecificity. These findings support the concept that the class I molecules themselves are the weak MLC stimulating determinants previously mapped to the HLA-A and B regions of the major histocompatibility complex.
mesh_terms: D002478:Cells, Cultured; D002999:Clone Cells; D006680:HLA Antigens / Q000235:genetics*; D006801:Humans; D007519:Isoantigens / Q000276:immunology; D008213:Lymphocyte Activation; D007959:Lymphocyte Culture Test, Mixed; D008285:Major Histocompatibility Complex; D010641:Phenotype; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D006680:HLA Antigens; D007519:Isoantigens