Background: Hematopoietic stem cell transplants are routinely used to treat patients with cancers and other disorders of blood and immune systems. Osteoblasts constitute part of the stromal cell support system in marrow for hematopoiesis by participating in the formation of the HSC niche. It is believed that interaction between hematopoietic cells and bone forming osteoblasts regulate each other’s function. It is established that acute blood loss in animal models activates bone formation and niche development because of EPO stimulation. In this experimental study we have examined the co-culture of HSCs derived from cord blood which treated with EPO in vitro, on osteoblastic differentiation of mesenchymal stem cells.

Materials and Methods: In this experimental study MSCs isolated from bone marrow and co-cultured with CD 34+ CD38- HSCs isolated from cord blood. These co-cultured cells were treated with different doses of erythropoietin for 14 days, after that RNA were extracted from MSCs and analysed with RT-PCR to evaluate the expression of osteopontin and osteocalcin. Alizarin red and alkaline phosphatase staining were done for osteoblastic differentiation.

Results: Osteopontin and osteocalcin were expressed in MSCs. Cellular staining were positive for osteoblastic differentiation. Differentiated cells expressed osteoblastic markers.

Conclusion: These data suggest that EPO regulates the osteoblastic differentiation from bone marrow MSCs in vitro.