Chronic administration of transforming growth factor-beta suppresses erythropoietin-dependent erythropoiesis and induces tumour necrosis factor in vivo

Abstract
Transforming growth factor beta is a known inhibitor of the proliferation and differentiation of early haematopoietic progenitors but has no effect on mature erythroid cells in vitro. Mice injected with rhTGF beta 1 exhibited severe and progressive suppression of erythropoiesis manifested by a decline of reticulocyte count, marrow erythroblasts and marrow and spleen CFU-E, which could be prevented by administration of erythropoietin. This suppression of erythropoiesis was associated with the appearance of tumour necrosis factor in the blood, development of pronounced cachexia and depression of serum erythropoietin levels. TGF beta induces TNF in vivo that leads to cachexia, decrease of serum erythropoietin levels and suppression of erythropoietin dependent erythropoiesis.