Perivascular niche, mesenchymal

As mentioned previously, to circumvent sourcing issues, several groups have identified alternative sources of neonatal and adult mesenchymal progenitor cells, from adipose tissue, skeletal muscle, umbilical cord tissue [11], and other organs. It is now generally accepted that mesenchymal progenitor cells, including bone marrow mesenchymal cells, are perivascular cells [12], and reside in the perivascular niche [13,14], which may explain their relative abimdance in more vascular tissue like adipose and muscle. 

Shi S, Gronthos S. Perivascular niche of postnatal mesenchymal stem cells in human bone marrow and dental pulp. J Bone Min Res Off J Am Soc Bone Min Res... 

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