BIOLOGICAL FEATURES OF HUMAN T-ACTIVATED KILLER CELLS

Objective: To investigate the immunobiological essence of T’activated killer (T-AK) cells induced byanti-CD, monoclonal antibody (CD3McAb) andrecombinant interleukin-2 (rIL-2) co-stimulation.Methods: The cytomorphology, t phenotype andcytotoxicity of T-AK cells generated from humanperipheral blood mononuclear cells (PBMC) weredetermined. Results: T-AK cells were similar toactivated lymphoblasts in morphology, more than 90%of T-AK cells expressed the phenotypes 6f Tlymphocytes (CD,+, CD,+), and 20%--50% of the cellswere NK-like phenotype (CD,.+, CD,.+), some of themexpressed IL-2 receptor (CDZ,+), CD38 antigen (CD,,+)and MHC-II antigen (HLA-DR+) characteristic marksfor the activated T lymphocytes. T-AK cells attackingtargets were morphologically large volumes withgranules and mainly contained CD,+ and CD,.+ cells. TAK cells possessed high tumoricidal activities againstNK-sensitive K562 cells and NK-resistant Ran cells, thecytotoxicity was composed of mainly CD,McAbactivated CD,AK activity (~50%), IL-2 induced LAKactivity (-30%), NK activity (~10%) and the activities ofinhibitory factors in T-AK supernatant (~10%).Conclusion: T-AK cells are a heterogeneous cell.population consisting of mainly activated T lymphocytesand NK-like cells, the main part of T-AK cytotoxicity isthe common activities of CD,AK cells and LAK cells.