Fig. 8

Chondrogenesis of synovium, marrow, and adipose cMSCs. Passage 2 cMSCs were evaluated for chondrogenesis using the micromass pellet technique: 5 × 10⁷ cells from each cMSC preparation were pelleted in triplicate and incubated for 21 days in chondrogenic medium with media exchange twice weekly. a Pellets were photographed (gross images, bar = 300 μm), formalin fixed, and sectioned for histology. Pellets were positive for proteoglycan (toluidine blue) and collagen type II (10× objective, bar = 150 μm), although the intensity of staining varied across donor and tissue source of cMSC. b Pellet morphometry for a representative donor (mean ± SD). c Mean ± SD pellet area (mm²) of chondrogenic pellets for all 15 cMSC preparations. Data are reported in descending order for each tissue. For b and c, a, b, c denote significant differences between tissue source of cMSCs (p < 0.01)