Table 4.
Summary of Potential Chondroprogenitor-Specific Markers.
| Markers | Chondroprogenitors | Chondrocytes | IHC cartilage | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Chondroprogenitor specific markers | CPC; articular cartilage derived progenitors isolated by fibronectin adhesion assay22 | Migratory progenitors from bone marrow with chondrogenic potential16 | Perichondrium chondroprogenitors18 | Based on FACS cell sorting/location and greater chondrogenic potential | Uncultured passage 026 | Monolayer 24 hours33 | Monolayer 2 weeks33 | Serial passages (P1-P6)22,31,32,34 | Zonal distribution |
| SZ/MZ/DZ4,13 | |||||||||
| CD9 (tetraspan family)13 | DU | DU | DU | + | 5% | Monolayer culture; 18-fold increase | DU | DU | |
| CD29 (Integrin β1)48 | DU | + | DU | DU | + | P5—95.2% | + | ||
| Cartilage matrix | |||||||||
| CD49c (Integrin α3)31,48 | DU | + | DU | DU | DU | 66.5% | 84% | P1 to P6—2.4-fold upregulation | + |
| Cartilage matrix | |||||||||
| CD49e (Integrin α5)16,49 | P2—99% | + | DU | DU | +/− | 94.2% | 99.9% | P5—0.7% | DU |
| CD4450 | DU | + | DU | DU | + | 97.6% | 91.8% | P5—95.6% | Chondrocytes SZ |
| CD54 (ICAM-1)35 | DU | DU | DU | + | 98.8% | 88.5% | 78.4% | P1-P6—2.6-fold upregulation | + |
| All zones | |||||||||
| CD14651 | DU | DU | DU | + | − | − | DU | + | − |
| P2 ≃ 44% | |||||||||
| P5 ≃ 90% | |||||||||
| CD1515,31 | DU | DU | DU | DU | + | 94% | 84.6% | P1 to P6—maintained expression | DU |
| CD16622,33,52 | DU | DU | DU | + | + | 35.2% | 92.3% | P5—96.6% | + |
| SZ and MZ (coexpress CD105) | |||||||||
FACS expression values are expressed in mean %. − = negative expression; + = positive expression; DU = data unavailable (as far as our knowledge); P = passage; IHC = immunohistochemistry; SZ = superficial zone; MZ = mid-zone; DZ = deep-zone; BrdU = bromodeoxyuridine; PD = population doubling.