Tsmu solution improves rabbit osteochondral allograft preservation and transplantation outcome

To compare the effects of Tsmu solution with vitrification on chondrocyte viability and examine histological and biomechanical properties of osteochondral allografts (OCAs) after storage, OCAs from femoral condyles of New Zealand rabbits were harvested, stored for 35 days in Tsmu solution or by in vitro vitrification, and subjected to in vivo and in vitro assays. Stored OCAs were transplanted into knee femoral condyle cartilage defects in recipient rabbits. Chondrocyte viability and histological changes of cartilage grafts were assessed in vitro. Gross assessment, chondrocyte viability, histological assessment, OCA biomechanics, and immunological markers were evaluated in vivo 6 months after transplantation. Fresh OCAs served as in vitro and in vivo controls. Chondrocyte viability and scores for cartilage surface and histological quantitative assessment were superior for Tsmu solution compared with vitrification, but inferior compared with fresh OCAs in vitro and in vivo. With the exception of interleukin 6 content, biomechanical features of samples stored in Tsmu solution were superior to vitrification, and inferior to fresh OCAs in vivo. Thus, Tsmu solution provided suitable storage that improved chondrocyte viability, intact OCA cartilage matrix architecture, and transplantation outcomes.