ABSTRACT
The ability of mesenchymal stem cells [MSCs] to differentiate into other cell types makes these cells an attractive therapeutic tool for cell transplantation. In order to provide a source of human MSCs for autologus cell-based therapy, we have expanded MSCs from the bone marrow and analyzed the biological identities and transdifferentiation potential. The bone marrow of healthy donors was aspirated from the iliac crest. The adjacent cells expanded rapidly and maintained with periodic passages until a relatively homogeneous population was established. The identification of these cells was carried out by differentiation potential into the osteocytes and adipocytes. Transdifferentiation of human MSCs into hepatocyte-like cells was undertaken in response to a specific culture condition. The differentiation of MSCs into osteoblast is determined by deposition of a mineralized extracellular matrix. Adipocytes are identified by their morphology and staining. Hepatic cells were demonstrated in vitro functions characteristic of liver cells. We have defined conditions under which human MSCs can be isolated and expanded from human bone marrow. These cells can be amplified about 10[8]-fold in 6 weeks, and are capable of transdifferentiation into the cells of another developmental lineage