Exercise and T-lymphocyte function: a comparison of proliferation in PBMC and NK cell-depleted PBMC culture

This study utilized recently developed microbead technology to remove natural killer (NK) cells from peripheral blood mononuclear cell (PBMC) preparations to determine the effect of acute exercise on T-lymphocyte function, independent of changes in lymphocyte subpopulations. Twelve well-trained male runners completed a 60-min exercise trial at 95% ventilatory threshold and a no-exercise control trial. Six blood samples were taken at each session: before exercise, midexercise, immediately after exercise, and 30, 60, and 90 min after exercise. Isolated PBMC and NK cell-depleted PBMC were stimulated with the mitogen phytohemagglutinin. Cellular proliferation was assessed by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide dye uptake. In the PBMC cultures, there was a significantly lower mitogen response to phytohemagglutinin in exercise compared with the control condition immediately postexercise. There were no significant differences between the control and exercise conditions in NK cell-depleted PBMC cultures or in the responses adjusted for the percentage of CD3 cells. The present findings do not support the view that T-lymphocyte function is reduced after exercise.