Differentiation of human embryonic stem cells into bipotent mesenchymal stem cells.

Mesenchymal stem cells (MSCs) are multipotent progenitors that can be found in many connective tissues, including fat, bone, cartilage, and muscle. We report here a method to reproducibly differentiate human embryonic stem cells (hESCs) into MSCs that does not require the use of any feeder layer. The cells obtained with this procedure are morphologically similar to bone marrow MSCs, are contact-inhibited, can be grown in culture for about 20 to 25 passages, have an immunophenotype similar to bone marrow MSCs (negative for CD34 and CD45 and positive for CD13, CD44, CD71, CD73, CD105, CD166, human leukocyte antigen [HLA]-ABC, and stage-specific embryonic antigen [SSEA]-4), can differentiate into osteocytes and adipocytes, and can be used as feeder cells to support the growth of undifferentiated hESCs. The ability to produce MSCs from hESCs should prove useful to produce large amounts of genetically identical and genetically modifiable MSCs that can be used to study the biology of MSCs and for therapeutic applications.