FACTORS CONTROLLING HEMOPOIESIS: EXPERIMENTAL OBSERVATIONS ON THEIR ROLE IN POLYCYTHEMIA VERA

Abstract

Groups of normal rats rats were injected daily for 2 weeks with the thermostable or ether-soluble fractions of plasmas from 16 patients with active polycythemia vera and 8 in therapeutic remission. The recipients of each of these plasma extracts developed erythrocytosis due to the production of microcytes with decreased osmotic resistance, reticulocytosis, and myeloid erythrocytic hyerplasia without evidence of enhanced hemoglobin synthesis. Thrombocytosis was also present in these animals, and larger doses induced leukocytosis as well. The latter was chiefly due to a neutrophilia and was accompanied by myeloid granulocytic hyperplasia. All values returned promptly to normal after the injections were stopped. These findings are in accord with the thesis that enhanced humoral factor activity may be of pathogenetic significance in polycythemia vera.