The different lineage-specific biological properties of articular cartilage and subchondral bone present a great challenge in the construction of bi-lineage scaffolds for simultaneous osteochondral regeneration. To overcome this challenge, strontium incorporated calcium silicate (Sr-CS) ceramic was prepared for bi-lineage formation of scaffolds in this study. The positive result of Sr-CS in the regeneration of osteochondral defects was first proven by its improved effect on the osteogenesis and chondrogenesis induction of mesenchymal stem cells (MSCs). After that, scaffold-mediated macrophage polarization between classically activated inflammatory macrophages (termed M1 Phi) and alternatively activated inflammatory macrophages (termed M2 Phi) was assayed to investigate whether the incorporation of Sr into calcium silicate could alter host-to-scaffold immune response. Furthermore, the interactions between Sr-CS pretreated macrophages and MSCs differentiation were performed to prove the enhancement effect of suppressed inflammatory response on osteogenesis and chondrogenesis. In vivo transplantation showed that the Sr-CS scaffolds distinctly improved the regeneration of cartilage and subchondral bone, as compared to the calcium silicate scaffolds. On the one hand, the mechanism attributes to enhancement of strontium on the osteogenic and chondrogenic differentiation of MSCs. On the other hand, the reason can partially be attributed to suppressed synovial inflammatory response, which has improved effects on enhancement of osteogenesis and chondrogenesis. These findings suggest that monophasic Sr-CS scaffolds with a bi-lineage conducive property and an inflammatory response regulatory property represents a viable strategy for simultaneous regeneration of osteochondral defects.
[1]Shanghai Jiao Tong Univ, Dept Orthopaed Surg, Affiliated Peoples Hosp 6, 600 Yishan Rd, Shanghai 200233, Peoples R China.
[2]Shanghai Jiao Tong Univ, Shanghai Peoples Hosp 9, Coll Stomatol,Shanghai Key Lab Stomatol, Dept Oral & Craniomaxillofacial Sci,Sch Med,Natl, Shanghai, Peoples R China.
[3]Shanghai Res Inst Stomatol, Shanghai, Peoples R China.
[4]Shanghai Univ Med & Hlth Sci, Shanghai Peoples Hosp 6, Dept Orthopaed Surg, East Campus, Shanghai, Peoples R China.
(8.0+极速模式)