TRANSFERRIN-BINDING CAPACITY BY RAT BONE-MARROW POPULATIONS CONTAINING DIFFERENT PROPORTIONS OF ERYTHROID-CELLS

The transferrin-binding capacity of rat bone marrow cells and differen t erythroid-enriched populations from rat bone marrow has been studied and compared with that previously reported for pure reticulocyte popu lations. Two components with different transferrin-binding capacities were found. The one with higher affinity was present mainly in erythro id cells and showed an association constant similar to that observed i n reticulocyte populations. The component with a lower transferrin aff inity was observed mainly in bone marrow fractions containing low prop ortions of erythroid cells.