Influence of continuous-flow blood separator leucophoresis on in vitro functions of human lymphocytes

The influence of continuous-flow blood separator leucophoresis on these in vitro functions of human lymphocytes was studied. In ten separation experiments, lymphocyte functions were examined in the presence and absence of mononuclear phagocytes before, during and at the end of continuous flow leucophoresis. Cell surface markers and effector functions in spontaneous cell-mediated cytotoxicity (SCMC) and antibody-dependent cellular cytotoxicity (ADCC) assays did not change significantly under the conditions of leucophoresis. By contrast, separator lymphocytes exhibited a significantly increased mitogenic response to pokeweed mitogen and PPD. Removal of mononuclear phagocytes corrected for this phenomenon. PHA and Con A responses were not affected by leucophoresis, nor was the number of circulating haemopoietic stem cells (CFU-C) significantly altered during a 4 hr continuous flow blood separator run.