Figure 1. Isolation, expansion, seeding, and chondrogenic differentiation of BMSCs.
A. A tissue-culture flask (T150) containing isolated BMSCs and expansion medium. B. Adherent, human BMSCs on the surface of a tissue-culture flask demonstrating a characteristic spindle-shaped morphology during expansion (10× magnification). C. Re-suspension of BMSCs in chondrogenic medium within a 50 ml conical tube prior to scaffold seeding. D. Collagen I scaffold placement into the empty well of a 24 well culture plate using forceps. E. Micropipetting of a BMSC-chondrogenic medium suspension onto the central area of a collagen I scaffold. F. Extracellular cartilaginous proteoglycans stained with safranin O following three weeks of chondrogenic differentiation of human BMSCs seeded within a collagen I scaffold. Remnant collagen I scaffold is stained with fast green counterstain [staining protocol described in detail by Bornes et al. (2015); 10× magnification].