Purified human transferrin and "transferrin" released from sorted T8+ lymphocytes suppress release of granulocyte-macrophage colony-stimulating factors from sorted T4+ lymphocytes stimulated by phytohemagglutinin.
Nonadherent, low-density E-rosette-positive human peripheral blood cells were separated into T4+ and T8+ lymphocytes by immuno-fluorescence-activated cell sorting (FACS) with monoclonal antibodies OKT4 and OKT8. Both T4+ and T8+ lymphocytes released granulocyte-macrophage colony-stimulating factors (GM-CSF) in response to phytohemagglutinin (PHA). Purified iron-saturated human transferrin (TF) suppressed release of GM-CSF only from the T4+ subset of lymphocytes. A TF-type inhibitory activity was released from the T8+ subset of lymphocytes alone, and this inhibitory activity, as well as that in purified TF, was inactivated by preincubation with antihuman TF monoclonal antibody (HT/1). These studies suggest that, at least in vitro, subsets of T-lymphocytes and TF may be involved in the regulation of myelopoiesis.
D002469:Cell Separation; D006801:Humans; D007377:Interleukin-3 / Q000378:metabolism*; D010835:Phytohemagglutinins / Q000494:pharmacology; D013601:T-Lymphocytes / Q000145:classification / Q000378:metabolism*; D014168:Transferrin / Q000378:metabolism / Q000494:pharmacology*
D007377:Interleukin-3; D010835:Phytohemagglutinins; D014168:Transferrin