ABSTRACT
Human LAK cells induced from peripheral blood mononuclear cells with recombinant interleukin2 (rIL-2) incubation, can be cloned in semisolid medium and proliferated well in liquid cultures containing rIL-2. Phynotypie analysis by flow cytometry showed that these cloned LAK cells were T_3(+), T_4(-), T_8(+), Tac(+), DR(+) and NKH1(-)/(+). Cultured with 1?10~5/ml normal bone marrow mononuelear cells (BMMNC)for 0.5-hr prior to semisolid culture system for CFU-GM, the cloned LAK ceils at 2?10~5/ml showed inhibitory effect on CFU-GM that the colonies were decreased by 43.8% of control though 0.5 or 1?10~5/ml LAK cells did not. Morever, a dose-dependent inhibition of CFU-GM was noted when LAK cells pre-inbated with BMMNC for 4-hr in doses of 0.5 -4?10~5/ml that the inhibitory rates of CFU-GM were 58.8, 67.5, 88.8 and 96.3% at0.5, 1, 2, 4?10~5/ml LAK cells addition respectively. Using double-layer agar cultures, inhibitory activity for CFU-GM was also observed only when LAK cells at 4?10~5/ml without contacted with BMMNC. No significant difference of inhibitory effects on CFUGM growth was found between autologous and allogenie clotted LAK cells under same condition. These data suggeste that LAK cells inhibited growth of myeloid progenitor cells without MHC-restriction and the mechanism might involve cell-to-cell interaction and/or some soluble factors secreted by LAK cells.