Insulin stimulates erythroid colony formation independently of erythropoietin*

Abstract

Summary. The effect of insulin on the proliferation of late stage erythroid precursor cells (CFU‐e) from fetal mouse liver and aduit bone marrow was studied in a serum‐free culture system. Insulin in supraphysiological concentrations (> 10 ⁻⁸m) stimulated erythroid colony formation independently of Ep. The combined effect of Ep and insulin was smaller than the surn of their single effects. The number of colonies obtained with insulin was linearly related to the number of plated cells. These results suggest that insulin stimulates erythroid colony formation by a direct action on CFU‐e.