Mesenchymal stem cells can be derived from a diverse range of tissues. Originally, Friedenstein et al. isolated MSCs from the bone marrow (BM) and stroma of the spleen and thymus.[1][2] MSCs have since been derived from tissues as varied as the brain, spleen, liver, kidney, lung, bone marrow, muscle, thymus, and pancreas.[3]  However, bone marrow aspirates are still considered to be the most convenient and enriched source of MSCs.[4]

Fetal tissue also contains MSCs, with common sources including umbilical cord blood and fetal placenta. These sources may represent ontogenetically younger MSCs. Evidence exists that MSCs from fetal sources can undergo more cell divisions before they reach senescence than MSCs from adult tissue.[5] [Read more…]