An aligned-to-random PLA/PCL/COL1 bilayer electrospun scaffold loaded with exosomes of bone marrow-derived mesenchymal stem cells promotes tendon-to-bone healing in rats.

The regeneration of tendon-to-bone interface remains a significant clinical challenge due to the highly complex structure, composition, cell population, and mechanical properties of the interface. In this study, polylactic acid (PLA), polycaprolactone (PCL) and type I collagen (Col1) were used as raw materials to prepare a tendon-to-bone interface biomimetic scaffold through electrospinning technology. The nanofiber scaffold features an aligned-to-random bilayer structure mimicking the native ten-don-to-bone interface. Furthermore, when loaded with exosomes derived from bone marrow-derived mesenchymal stem cells (BMSC-Exos), the biomimetic scaffold synergistically promotes ten-don-to-bone regeneration. Our results demonstrate that the biomimetic scaffold is biocompatible and promotes cells adhesion, proliferation, and differentiation. In vivo experiments using a rat tendon-to-bone injury model demonstrated that PLA/PCL/COL1&BMSC-Exos scaffold significantly increased fibro-cartilage thickness, improved collagen fiber alignment, and enhanced biomechanical properties, with concurrent improvement in gait performance. The biomimetic scaffold represented a promising therapeutic approach for addressing tendon-to-bone healing and advancing clinical practices in ten-don-to-bone regeneration.

Keywords

Bone marrow-derived mesenchymal stem cells, Electrospun scaffold, Exosomes, Tendon-to-bone healing

Conflict of interest statement

Declaration of competing interest The authors affirm that they have no known financial or interpersonal conflicts that would have affected the research presented in this study.