Endothelial progenitor cells (EPCs) in circulation are originally thought to be mobilized from bone marrow (BM) and bone marrow mononuclear cells (BMMNCs) are extensively used for the induction of EPCs in vitro. In literature, various basal media have been employed for support the differentiation and growth of putative EPCs from BMMNCs. However, it remains unknown whether the basal culture medium affects the biological behaviors of EPCs. The aim of this work was to assess the characteristics and angiogenic activity of the putative EPCs induced from BMMNCs in two basal media: endothelial growth medium-2 (EGM-2) and Dulbecco's modified eagle medium (DMEM). Unfractioned BMMNCs from chicken were cultured in either EGM-2 or DMEM medium containing identical supplements. Cell morphology was constantly monitored using light microscope. The expression of progenitor marker CD133 and endothelial makers CD31 and VEGFR-2, ability of the cells to uptake Dil-labeled acetylated low density lipoprotein (Dil-ac-LDL) and to bind lectin Ulex europaeus agglutinin 1, migration capacity and angiogenic activity was determined on day 14 of plating.  BMMNCs cultured in EGM-2 were morphologically different from those in DMEM and had higher mRNA level of CD133 and CD31. The Dil-ac-LDL/lectin dual-positive cells in EGM-2 did not differ from that in DMEM. However, the cells in EGM-2 had increased migration capacity and also formed tubular networks on Matrigel, whereas those in DMEM did not. Taken together, these results suggest the choice of basal culture medium has significant influence on the differentiation of BMMNCs to EPCs.

Key words: Basal culture medium, Bone marrow mononuclear cell, Endothelial progenitor cells