Multi-functionalized nanofibers with reactive oxygen species scavenging capability and fibrocartilage inductivity for tendon-bone integration

The presence of excessive reactive oxygen species (ROS) after injuries to the enthesis could lead to cellular oxidative damage, high inflammatory response, chronic inflammation, and limited fibrochondral inductivity, making tissue repair and functional recovery difficult. Here, a multifunctional silk fibroin nanofiber modified with polydopamine and kartogenin was designed and fabricated to not only effectively reduce inflammation by scavenging ROS in the early stage of the enthesis healing but also enhance fibrocartilage formation with fibrochondrogenic induction in the later stages. The in vitro results confirmed the antioxidant capability and the fibrochondral inductivity of the functionalized nanofibers. In vivo studies showed that the multifunctional nanofiber can significantly improve the integration of tendon-bone and accelerate the regeneration of interface tissue, resulting in an excellent biomechanical property. Thus, the incorporation of antioxidant and bio-active molecules into extracellular matrix-like biomaterials in interface tissue engineering provides an integrative approach that facilitates damaged tissue regeneration and functional recovery, thereby improving the clinical outcome of the engineered tissue.