Erythropoietin-stimulated endothelial cells support erythroid cell differentiation of CD34(+) haematopoietic progenitors.

BACKGROUND AND OBJECTIVES

Endothelial cells provide a unique medium for the proliferation and white lineage differentiation of haematopoietic progenitor cells (HPC). Whether this quality can be exploited to facilitate the differentiation of erythroid precursors is not yet known.

MATERIALS AND METHODS

Haematopoietic progenitor cells derived from cord blood were cultured for 3 weeks in erythropoietin-stimulated supernatants with (n = 6) or without cyclosporine A (CSA, n = 6). Cell count, phenotype and morphology were assessed on a weekly basis, and the haemoglobin content was analysed. These cultures were compared with erythroid differentiation induced by cytokines only (n = 6).

RESULTS

Endothelial supernatants combined with CSA led to equivalent numbers of CD71(+) erythroblasts after 1 week as cytokines only. The purity of glycophorin-positive, CD45-negative cells was higher in cells generated in endothelial supernatants than in cytokine-based media. Additional prostaglandin E2 induced a change from fetal to adult haemoglobin.

CONCLUSION

For the generation of erythroblasts from HPC, endothelial supernatants are a simple and cost-effective alternative to culture conditions based on cytokines.