Sensitivity of erythroid progenitors to recombinant growth factors in the diagnosis of myeloproliferative disorders.

Sixty-six adults were studied with the aim of establishing positive diagnostic criteria for myeloproliferative disease. Erythroid colony formation from peripheral blood progenitors was assayed in a serum-free culture system with the addition of recombinant human growth factors. Endogenous colonies were more frequent in myeloproliferative disease than controls. The mean number of clusters per erythroid burst (BFU-e) in cultures with erythropoietin only was lower in primary proliferative polycythemia (polycythemia vera, PPP) than controls. In PPP, primitive BFU-e demonstrated greater dependence on interleukin 3 than controls, and mature BFU-e more susceptibility to inhibition by alpha-interferon. The findings indicate an abnormal response to several different cellular messengers in PPP, and permit an effective diagnostic discrimination from non-clonal polycythemias.