Ex vivo cartilage explant model for the evaluation of chondrocyte-targeted exosomes

There is no efficient tracking system available for the therapeutic molecules delivered to cartilage. The dense matrix covering the cartilage surface is the main biological barrier that the therapeutic molecules must overcome. In this study, we aimed to establish a system that can dynamically and effectively track the therapeutic molecules delivered to cartilage. To this aim, we adopted bovine and human cartilage explants as ex vivo models for chondrocyte-targeted exosome dispersion. The efficiency of drug delivery was evaluated using frozen sections. The results of this study showed that the penetration and distribution of chondrocyte-targeted exosomes in cartilage explants can be tracked dynamically. Thus, ex vivo cartilage explants provide an effective and economic system to evaluate therapeutic drugs encapsulated in chondrocyte-targeted exosomes in preclinical studies.