PAF and haematopoiesis: IX. Platelet-activating factor increases DNA synthesis in human bone marrow cells.

Platelet-activating factor (PAF) is present in human bone marrow leading us to investigate its effect on human bone marrow cell proliferation. While PAF (0.1 μM to 1 nM) stimulates the incorporation of [3H]thymidine by freshly isolated adherent human bone marrow cells, PAF has no effect on non adherent cells. A non-metabolizable PAF agonist is more potent than PAF to stimulate thymidine incorporation in adherent cells. The precise role of PAF in human haematopoiesis in vivo remains to be clarified.