Defective in vitro growth of BFU-E of elderly subjects revealed by hydrocortisone.

The effect of aging on hematopoiesis and bone marrow exhaustion have long been debated. Unexplained anemia and impaired in vitro proliferation of erythroid precursors is frequently observed in the elderly. As hydrocortisone is known to increase the BFU-E in vitro growth, we have studied the response of BFU-E to hydrocortisone in a group of nonanemic elderly subjects. The BFU-E growth in methylcellulose from blood mononuclear cells (MNC), stimulated by lymphocyte-conditioned medium (LCM), either with or without hydrocortisone, of 10 subjects aged 76-91 years was compared with the BFU-E growth from MNC of a group of ten young subjects. While LCM induced a significant increase of BFU-E growth, both in young and old subjects, hydrocortisone induced a significant increase of BFU-E growth only in young subjects. This study shows that in the elderly, there is a latent defect of erythropoiesis, possibly consisting of a defective ability to modulate the receptors for erythropoietin on BFU-E, and that hydrocortisone offers a useful tool to identify it.