One-step strategy for cartilage repair using acellular bone matrix scaffold based in situ tissue engineering technique in a preclinical minipig model.

Cartilage defects are most commonly seen in the knee joint. However, due to the limited self-recovery ability of cartilage, the repair of articular cartilage defects is still a great challenge despite that various approaches have been proposed. We designed a strategy to induce cartilage repair using acellular bone matrix (ABM), thereby creating an appropriate microenvironment for the in-situ cells with an easy surgical application. An in vitro system demonstrated that the ABM scaffold could promote cell adhesion, growth, proliferation, and chondrogenesis of mesenchymal stem cells. This experiment was performed in a minipig cartilage repair model. The repaired tissue was hyaline-like cartilage according to the morphological and histological results. The mechanical properties of the repaired tissue were similar to those of normal cartilage. The integration of repaired tissue and normal tissue in the ABM+M group was better than those of other two groups. The ABM-based, one-stage, minimally invasive, in situ procedure for cartilage regeneration can potentially improve the treatment of articular cartilage defects.