Successful Vitrification of Human Osteochondral Dowels and Intact Femoral Condyle.

Abstract

ObjectiveCryopreservation via vitrification of articular cartilage (AC) will increase the availability of graft tissue for treating large joint defects. To advance this research area, we compared the effects of 2 cryopreservation protocols in which 10-mm diameter human osteochondral dowels were cooled and stored in liquid nitrogen vapor.DesignDowels collected from healthy human knee joints (n = 3 donors) of deceased donors were randomly assigned to Protocol 8 (430 min) or Protocol 2BWF (410 min). Post-warming chondrocyte viability was assessed and normalized to fresh controls.ResultsBoth protocols resulted in high chondrocyte viability after loading, vitrification, and rewarming (~80% of fresh control). Protocol 2BWF was subsequently used to vitrify and rewarm 3 human intact lateral femoral condyles. After rewarming, metabolic activity, normalized chondrocyte viability, histology, and matrix productivity were experimentally measured. Results documented ~82% of fresh chondrocyte viability post vitrification and rewarming, with similar results to the fresh control group on the other AC quality criteria.ConclusionThese results demonstrate that both Protocol 8 and Protocol 2BWF can preserve the quality of vitrified human AC in osteochondral dowels and human intact femoral condyles.