Decellularized Stem Cell Matrix: A Novel Approach for Autologous Chondrocyte Implantation-Based Cartilage Repair

Abstract

Cartilage defects due to injuries of the knee result in more than 200,000 surgical procedures annually. Current conservative and operative treatments prove inadequate at fully repairing/resurfacing the defects. The most promising cell-based therapy, autologous chondrocyte implantation (ACI), has evolved for generations and is successful in young patients though long-term clinical outcomes are not yet known. The major limitations for current ACI are autologous chondrocyte shortage and dedifferentiation during monolayer expansion. Stem cells, especially tissue-specific stem cells, may be able to overcome autologous chondrocyte shortage in future ACI treatment due to their self-renewal, multi-lineage differentiation potentials, and lack of ethical issues. Synovium-derived stem cells have been suggested to be a tissue-specific stem cell for cartilage regeneration due to their excellent chondrogenic capacities both in vivo and in vitro. For the concern about cell dedifferentiation during expansion, decellularized stem cell matrix could provide an ex vivo expansion system to rejuvenate and/or reprogram expanded cells in proliferation and chondrogenic potential. The combination of a tissue-specific stem cell and decellularized stem cell matrix would help provide large-quantity and high-quality cells to improve cartilage regeneration and benefit cartilage repair, which will greatly advance the development of next generation ACI in the near future.