Assembly of injectable stem cells for cartilage regeneration
Newswise – This study led by Professor Qiuyu Zhang (Northwestern Polytechnical University), Professor Ki-Bum Lee (Rutgers University) and Professor Liang Kong (School of Stomatology, The Fourth Military Medical University). They established a stem cell assembly based on injectable hybrid inorganic nanoscaffolds (IHI) and applied it to the regeneration of critical size cartilage defects.
Cartilage damage is often devastating and most of it is incurable due to the inherently low regenerative capacity of cartilage tissue. The rise of 3D stem cell culture systems has led to breakthroughs in developmental biology, disease modeling and regenerative medicine. For example, stem cells, when successfully transplanted, could initially secrete trophic factors to reduce inflammation at cartilage lesions and then differentiate into cartilage cells (for example, chondrocytes) for functional restoration. Nevertheless, there remain critical hurdles to overcome before the therapeutic potential of stem cell therapies can be realized. Limited control of chondrogenic stem cell differentiation live often resulted in compromised regeneration results. Additionally, due to the prevalence of oxidative stress and inflammation in the microenvironment of injury sites, stem cells frequently undergo apoptosis after injection.
To address these challenges, they demonstrated the development of an IHI 3D nanoscaffold-based stem cell assembly system for advanced 3D stem cell culture and implantation. The 3D-IHI nanoscaffold rapidly assembles stem cells into injectable tissue constructs through customized 3D cell-cell and cell-matrix interactions, deeply and homogeneously delivers chondrogenic proteins into the assembled 3D culture systems and induces in a controlled manner chondrogenesis by nanotopographic effects. Once implanted live in a rabbit cartilage injury model, the 3D-IHI nanoscaffold effectively modulates the dynamic microenvironment after cartilage injury through the integration of the aforementioned regenerative signals, and simultaneously removes reactive oxygen species using of a composition based on manganese dioxide. In this way, accelerated repair of cartilage defects with rapid tissue reconstruction and functional recovery is achieved both in the short and long term. Given the excellent versatility and therapeutic results of 3D-IHI nanoscaffold-based cartilage regeneration, it may provide promising means to advance a variety of tissue engineering applications. The first authors are Dr. Shenqiang Wang, Dr. Letao Yang and Professor Bolei Cai.