Initial characterisation of a lymphocyte-derived factor that is a potent stimulator of human endothelial cell...

Supernatants from cultured normal human peripheral blood mononuclear cells were incubated with umbilical vein endothelial cells. Prostacyclin production, lactate dehydrogenase release, and viability of the endothelial cells was measured. The supernatants caused changes in growth patterns and were potent stimulators of prostacyclin production. The source of the stimulating factor(s) was shown to be the lymphocyte sub-population. Preliminary characterization of supernatants revealed that more than one molecular species may be involved.