Regenerative therapies offer attractive alternatives for the treatment of osteochondral defects. Adipose-derived stromal vascular
fraction (SVF) cells allow the development of one-step surgical procedures by their abundant availability and high frequency.
In this pilot study we evaluated the in vivo safety, feasibility, and efficacy of this concept using scaffolds seeded with
freshly isolated (SVF) or cultured adipose stem cells (ASCs), and compared these to their acellular counterparts. Osteochondral
defects were created in medial condyles and trochlear grooves in knees of eight goats. Defects were filled with acellular
collagen I/III scaffolds or scaffolds seeded with SVF cells or cultured ASCs. Osteochondral regeneration was evaluated after
1 and 4 months by macroscopy, immunohistochemistry, biomechanical analysis, microCT analysis, and biochemistry. After 1 month,
no adverse effects were noted. Microscopic, but not macroscopic evaluation showed considerable yet not significant differences,
with cell-loaded constructs showing more extensive regeneration. After 4 months, acellular constructs displayed increased
regeneration, however, to a lesser degree than cell-treated constructs. The latter exhibited more extensive collagen type
II, hyaline-like cartilage, and higher elastic moduli, and their glycosaminoglycan content in the cartilaginous layer better
approached native tissue values. Moreover, their defect regions contained higher levels of regenerated, mature subchondral
bone with more intense collagen type I staining. SVF cells tended to perform best on all parameters. In summary, this pilot
study demonstrated the preclinical safety and feasibility of a one-step surgical procedure for osteochondral defect regeneration.
Similar regeneration was found between freshly isolated SVF cells and cultured ASCs. Larger studies with longer follow-up
are required to substantiate these findings.