Possible regulation of autologous mixed lymphocyte reaction by OKM1+ NK cells

T cells are stimulated by autologous non-T cells and interleukin 2 (IL-2) is produced in the conventional autologous mixed lymphocyte reaction (AMLR) in young healthy controls. The role of cells with natural killer (NK) cell markers (OKM1+ cells or Leu 7+ cells) in the AMLR was studied. There were significant inverse correlations between the percentage of input OKM1+ cells minus monocyte (OKM1+ NK cells) and either AMLR proliferation (gamma = -0.9, P less than 0.001) or IL-2 production (gamma = -0.75, P less than 0.01) in the AMLR cultures after 7 days measured at 7 days. A statistically significant correlation was observed between the percentage of input Leu 7+ cells and AMLR proliferation (gamma = -0.64, P less than 0.05), but not IL-2 production. These results suggest that the AMLR is controlled by OKM1+ NK, perhaps acting through IL-2 regulation.