MYELOFIBROSIS AND PROSTAGLANDINS: EFFECT OF PROSTAGLANDIN E1 ON COLONY-FORMING CELLS (CFU-GM)

Semisolid agar cultures of committed granulocyte monocyte precursors (CFU-GM) make it possible to study the regulation of normal and abnormal stem cells. In vitro growth of CFU-GM is dependent on the presence of specific stimulators, called CSA (colony stimulating activity) (Metcalf, 1977; Broxmeyer & Moore, 1978). The influence of CSA on CFU-GM may be inhibited by prostaglandins of the E series (Broxmeyer & Moore, 1978; Kurland et al, 1978). Recently it has been demonstrated that chronic granulocytic leukaemia (CGL) CFU-GM are insensitive to prostaglandin E1 (PGE1) over a wide range of concentrations that are inhibitory to normal CFU-GM development (Aglietta et al, 1980; Pelus et al, 1980; Taetle & Koessler, 1980). We report the effect of PGE1 on CFU-GM from patients with idiopathic myelofibrosis (MF).