Placenta as a reservoir of stem cells: an underutilized resource?

The placenta has gained more interest recently because it may potentially represent an important source of a variety of stem cells, including trophoblastic, haematopoietic, epithelial and mesenchymal stem cells (MSCs). 

Although it remains uncertain whether pluripotent stem cells persist during development beyond the first few weeks, the placenta has been demonstrated to contain various stem cell niches that may reflect the different embryonic origin of its components. 

Of relevance, the placenta has been reported to contain a population of broadly multipotent stem cells that also show expression of embryonic stem (ES) cells markers such as c-KIT, OCT4, SOX2, SSEA3, SSEA4, TRA-1-60 and TRA-1-81.  

These cells have a mesodermal phenotype, but demonstrate a broad differentiation potential that is not limited to mesenchymal lineages, but extends also to hepatocytes, vascular endothelial, pancreatic and neuronal differentiation.  

Mesodermal cells may also be responsible, in vivo, for the immunomodulatory function of the placenta. They are phenotypically similar to those present in adult bone marrow, although they are easy to distinguish from the latter using gene and protein profiling and may have greater potential to respond to injuries. 

For example, renin and flt-1 are expressed uniquely in placental MSCs. Other cell types also populate the placenta and may be relevant for therapy, including for example, mature and immature haematopoietic progenitors giving rise to erythroid and myeloid lineages.


https://academic.oup.com/bmb/article/105/1/43/270811