Lyophilized platelet-rich fibrin functionalized injectable hydrogel microspheres for alleviating osteoarthritis in a rat model.

Abstract

BACKGROUND: Lyophilized platelet-rich fibrin (Ly-PRF) contains various growth factors that contribute to tissue regeneration and alleviation of osteoarthritis. Microfluidic hydrogel microspheres are the suitable delivery systems for delivering Ly-PRF to the articular cavity for the treatment of osteoarthritis. Therefore, the purpose of the present study was to construct hyaluronic acid methacrylonitrile acylationed (HAMA) microspheres encapsulating Ly-PRF (HAMA@Ly-PRF microspheres) and investigate their therapeutic efficacy in osteoarthritis. METHODS: Fresh PRF was prepared by centrifugation, and vacuum freeze-drying technology was utilized to prepare Ly-PRF. Subsequently, HAMA was synthesized by chemical synthesis, which could be crosslinked under exposure to ultraviolet light. Thereafter, HAMA and HAMA@Ly-PRF microspheres were fabricated using the microfluidic method. In vitro, the biocompatibility of HAMA@Ly-PRF microspheres and their effect on chondrogenic differentiation were tested. In vivo, a rat model of osteoarthritis was created to evaluate the alleviating effect of HAMA@Ly-PRF microspheres on osteoarthritis. RESULTS: The fresh PRF was located in the middle of the glass tube after centrifugation. The results of scanning electron microscopy showed that Ly-PRF had a honeycomb-like porous structure. The prepared HAMA and HAMA@Ly-PRF microspheres were uniform in size and shape, and exhibited porous structures as evidenced by the findings of scanning electron microscopy. The HAMA@Ly-PRF microspheres had good biocompatibility and could promote chondrogenic differentiation of C3H10T1/2 cells through the sustained release of transforming growth factor-β1 contained in Ly-PRF. In vivo, the HAMA@Ly-PRF microspheres alleviated osteoarthritis due to their promotive effect on chondrogenic differentiation. CONCLUSIONS: HAMA@Ly-PRF microspheres may alleviate osteoarthritis by the sustained release of growth factor from Ly-PRF. STRENGTHS AND LIMITATIONS.