Stimulating capacity of human lymphoid cell subpopulations in mixed lymphocyte cultures

The content and yield or B cells, T cells and monocytes were investigated in cell fractions separated from human peripheral blood by various techniques. These cell fractions, which were highly enriched for either B cells, T cells or monocytes, were tested for their capacity to stimulate allogenic peripheral blood mononuclear cells in mixed lymphocyte cultures (MLC). B cells were found to be strongly stimulatory. Monocytes stimulated strongly at low stimulator/responder cell ratios, while less stimulation was observed using larger amounts of cells. T cells were demonstrated to stimulate weakly, if at all.