In vivo Transfer of a Thrombopoietic Factor.

Abstract

Injection of plasma from rabbit donors made thrombocytopenic by Myleran or anti-platelet serum into 15 unstressed rabbit recipients raised platelet counts to 166% of control levels 4 days following transfer. These results are highly significant when compared to the mild thrombocytopenia produced in 15 rabbits receiving plasma from normal donors or when compared to the daily variations in platelet levels of 9 uninjected rabbits. The response of normal and splenectomized recipients was similar. These results suggest that plasma contains stimulatory and inhibitory factors which regulate platelet levels.