Table 1.

Identification of mesenchymal stem/progenitor cells in vivo.

Markers/ reporter systems	Organism	Tissue	Findings	Reference
In Vivo Localization
STRO-1, CD146	Human	Bone marrow	Perivascular location Can form bone with marrow	[20]
CD146	Human	Bone marrow	Reticular adventitial cells around sinusoids Can form bone with marrow Can self-renew in vivo	[21]
CD146 & CD271	Human	Bone marrow	Perivascular reticular cells Multilineage mesenchymal potential in vitro Can form bone with marrow	[22]
Sca-1 & PDGFR-α	Mouse	Bone marrow	Multilineage mesenchymal potential in vitro Arterial perivascular location adjacent to vascular smooth muscle cells Can give rise to perivascular stromal cells, osteoblasts and adipocytes in vivo	[23]
CD146, NG2, PDGFR-β	Human	Muscle, pancreas, adipose, placenta	Perivascular location Multilineage mesenchymal potential in vitro Can give rise to muscle and ectopic bone in vivo	[25]
In Vivo Lineage Tracing
Nes-GFP+ Nes-GFP; Col2.3− Cre; R26-LacZ Nes-CreERT2; RCE:loxP	Mouse	Adult bone and bone marrow	Nes-GFP Perivascular location Nes-GFP; Col2.3-Cre; R26-LacZ Multilineage mesenchymal potential in vitro Self-renew and contribute to ectopic bone formation Nes-CreERT2 Contribute to osteoblasts, osteocytes, and chondrocytes in vivo	[29]
Prx1-Cre; Ai9; CXCL12-GFP		Adult bone and bone marrow	Prx1-Cre Contribute to osteoblasts, osteocytes and CXCL12+ reticular cells in vivo	[36]
LepR-Cre; loxP- EYFP		Adult bone and bone marrow	LepR-Cre Perivascular stromal cells but not osteoblasts Express CXCL12, PDGFRα	[31]
Mx1-Cre; Rosa- YFP Osx-CreERt;Rosa- YFP Ocn-CreER; Rosa- YFP	Mouse	Adult bone and bone marrow	Mx1-Cre Contribute to osteoblasts in vivo Multilineage mesenchymal potential in vitro Osx-CreERt Transient source of osteoblasts Ocn-CreER Rapid turnover of mature osteoblasts on the endosteal surface Contribute to osteocytes	[40]
αSMA-GFP αSMA-Cherry αSMA-CreERT2; Ai9 (TdTomato)	Mouse	Adult bone and bone marrow	αSMA-GFP or αSMA-Cherry Perivascular location Osteogenic and adipogenic potential in vitro Contribute to osteoblasts in vivo αSMA-CreERT2 Contribute to osteoblasts and osteocytes in vivo Multilineage mesenchymal potential in vitro	[44, 45]
Osx-CreERt; R26R-LacZ ColI(3.2 kb)- CreERt; R26R- LacZ	Mouse	Embryonic bone	Osx-CreERt Labeled while in perichondrium Closely associated with invading vasculature Give rise to trabecular osteoblasts, osteocytes and stromal cells ColI-CreERt Not associated with vasculature Remain in cortical bone	[41]
Osx-Cre; mTmG; β-catfl/fl Osx-Cre; Ai9 Osx-CreERt; Ai9		Adult bone and bone marrow	Osx-Cre; β-catfl/fl Adipogenic potential in vitro Contribute to osteoblasts, osteocytes and adipocytes in vivo in adult mice Osx-Cre Contribute to perivascular stromal cells, osteoblasts and osteocytes Multilineage mesenchymal potential in vitro Osx-CreERt Embryonic cells contribute to perivascular stromal cells, osteoblasts, osteocytes and adipocytes in vivo	[42, 43]
PPARγ-GFP	Mouse	Adipose tissue	PPARγ-GFP Adipogenic potential in vitro Perivascular location Express aSMA, NG2 Contribute to adipocytes in vivo	[47]
Zfp423-GFP	Mouse	Adipose tissue	Zfp423-GFP Adipogenic potential in vitro Expressed by perivascular and endothelial cells	[48]
VE-Cad-Cre; R26R-LacZ VE-Cad-Cre; R26R-eGFP	Mouse	Adipose tissue	VE-cad-Cre Expressed by perivascular and endothelial cells, preadipocytes and adipocytes	[49]