SOURCES OF STEM CELLS

Bone marrow derived stem cells:
The priority location for HSCs is bone marrow and cord blood cells, and bone marrow transplantation has become synonymous with hematopoietic cell transplantation. In adults, under steady state conditions, the majority of HSCs live in bone marrow. Bone marrow also constitute 0.1% mesenchymal cells. Therefore, for production of mesenchymal stem cells bone marrow has to be expanded over a period of 4-6 weeks.

Umbilical cord derived stem cells:
Stem cells can be derived from the two parts of the umbilical cord, cord blood and Wharton jelly. The cord blood forms important source of mesenchymal and hematopoietic stem cells, while Wharton jelly forms an important source of mesenchymal stem cells. The cord blood HSCs have been noted to have a greater proliferative capacity than adult bone marrow HSCs. Umbilical cord mesenchymal cells (UC-MSCs) are immunologically privileged cells, which invokes only minimal immune reactivity, and UC-MSCs express MHC class I antigens and express low levels of MHC class II antigens, relatively less than BM-MSCs. As several studies currently suggest, UC-MSCs, like BM-MSCs, does not need HLA matching, thus, allowing for an allogeneic cell therapy source, as any donor can give cells to any other person without rejection or need of immunosuppressant drugs. Umbilical cord Mesenchymal stem cells may also possess some features of embryonically stem cells thus enhancing the potency of stem cells even in neurogenic diseases.