T-cell subset modulation of blood erythroid burst-forming unit proliferation.

Peripheral blood BFU-E are primitive erythroid progenitor cells that have been reported to exhibit an absolute dependence on T-cells for proliferation in the plasma clot system. The study reported here was undertaken to define the differential effects of TS and TH lymphocytes on proliferation of BFU-E. We investigated the effect of unfractionated T-cells, TS, and TH on in vitro growth of peripheral blood BFU-E. Cell populations were negatively selected by treatment with murine monoclonal antibodies (OKT-3, OKT-4, OKT-8) and C'. Our experiments suggest that proliferation of peripheral blood BFU-E exhibits an absolute requirement for T-cells. The capacity to enhance growth of BFU-E is approximately equal between normal unfractionated T-cells and TS and TH cells. The data suggest that the TH and TS cells defined by the OKT antibodies are not critical in the modulation of erythroid proliferation.