Temperature-activated PRP–cryogel for long-term osteogenesis of adipose-derived stem cells to promote bone repair

Abstract

Platelet-rich plasma (PRP) is widely used for wound healing with fairly good biocompatibility. However, it suffers from the burst release of growth factors as well as the activation with exogenous activators. In this study, we encapsulated PRP in a cryogel to address both these issues. As the cryogel was prepared in a subzero condition and could load PRP with tough covalent-bond crosslinkers, the activity of the autologous activators in the pristine PRP could be effectively saved and the release rate of the growth factors could be effectively reduced. At 37 °C, the remaining autologous activators could activate PRP without the need of exogenous activators to continuously release growth factors for more than 24 days. The prepared PRP–cryogel could then promote the long-term osteogenesis of adipose-derived stem cells (ADSCs). As a bone tissue engineering strategy, the combination of PRP, cryogel, and ADSCs provides temperature-activated PRP and slow-release growth factors for the long-term osteogenesis of ADSCs to enhance bone repair in rats.