[In vitro studies of anemia accompanying a chronic inflammatory processes and neoplasms. Effect of cachectin (TNF-alpha) and lymphotoxin (TNF-beta) on human erythropoiesis].

The influence of tumor necrosis factor alpha and beta, on the clonal growth of human erythroid progenitors, from different stages of development--early BFU-E, late BFU-E, and CFU-E--in vitro cultures was evaluated. In the cultures of human bone marrow cells enriched in clonogenic progenitors the inhibitory effect on erythroid colony formation, was confirmed. The influence of TNF-alpha was more profound in comparison to TNF-beta and also visible at early BFU-E level. We did not however, observe the inhibitory effect, of both inflammatory cytokines, on granulocyte-monocytic colony formation. These data demonstrated that TNF-alpha and beta inhibit selectively the growth of the erythroid progenitors. Simultaneously it was found that early erythroid progenitors did not respond, to the kit ligand, in the presence of TNF-alpha.