Research on mesenchymal stem cells (MSC) is progressing with increasing popularity. Currently there are a significant number of clinical trials exploring the use of MSCs for the treatment of various diseases including graft-versus-host disease, Crohn’s disease, myocardial infarction, stroke, bone defects, diabetes, and wound repair (www.�clinicaltrails.gov). At the same time, there are questions associated with MSCs in terms of their isolation, culture expansion, phenotype, multipotential differentiation, and transplantation efficiency. This chapter outlines the current status of the field and emphasizes the need for clearly defined protocols to better define the function and use of MSCs in cell therapy.
