Wnt3a-transfected Bone Marrow Stromal Cells Amplify Umbilical Cord Blood Derived CD34～+ Hematopoietic Stem/Progenitor Cells And Promote Differentiation Towards Erythoid Lineages

Wnt3a is a particularly attractive candidate for amplification of hematopoietic stem/progenitor cells. Wnt3a protein is important for WNT signaling and the protein had hardly been isolated in an active form. In this study, a Wnt3a-transfected bone marrow stromal cells which could secret active Wnt3a protein has been developed. The results showed that Wnt3a-transfected BM stromal cells amplified CD34~+ hematopoietic stem/progenitor cells effectively, including CD34~+ hematopoietic cells, colony-forming cells(CFCs), high-proliferative-potential colony-forming cells (HPP-CFCs), and Long-term culture-initiating cells (LTC-ICs) during short-term liquid coculture with Umbilical Cord Blood Derived CD34~+ cells. Wnt3a-transfected BM stromal cells also promoted the differentiation of CD34~+ hematopoietic stem/progenitor cells towards erythroid lineages by a erythroid differentiation inducing cytokines. Furthermore, it seems that Wnt3a upregulates genes such as H0XB4, Gata-1 and EKLF to regulate the differentiation of CD34+ hematopoietic stem/progenitor cells.In summary, the results suggest that Wnt3a-transfected BM stromal cells can amplify CD34~+ hematopoietic stem/progenitor cells and direct them to differentiate towards erythroid lineages under some conditions.