In Vitro Osteogenesis of Synovium Mesenchymal Cells Induced by Controlled Release of Alendronate and Dexamethasone from a Sintered Microspherical Scaffold

In vitro osteogenesis was successfully achieved with synovium-derived mesenchymal stem cells (SMSCs), which intrinsically have a strong chondrogenic tendency, by in situ release of alendronate (AL) and dexamethasone (Dex) from poly(lactic-co-glycolic acid) (PLGA)/hydroxyapatite (HA) sintered microspherical scaffold (PLGA/HA-SMS). Cumulative release profiles of AL and Dex from PLGA/HA-SMS and the influence on SMSCs osteogenic commitment were investigated. SMSCs seeded in Al-/Dex-loaded PLGA/HA-SMS (PLGA/HA-Com-SMS) exhibited significant osteogenic differentiation, as indicated by high yields of alkaline phosphatase (ALP) and bone calcification. In addition, mechanical properties (compressional) of PLGA/HA-Com-SMSs were also evaluated and approved. In conclusion, by promoting osteogenic commitment of SMSCs in vitro, this newly designed controlled-release system opens a new door to bone reparation and regeneration.