Decellularized Human Umbilical Cord Wharton Jelly Scaffold Improves Tendon Regeneration in a Rabbit Rotator Cuff Tendon Defect Model

Background: Owing to limited self-healing capacity, failure of rotator cuff tendon healing is a common complication after surgery. Biological scaffolds have garnered attention owing to their potential to enhance healing outcomes. Purpose: To verify the effect of the decellularized umbilical cord Wharton jelly (DUCWJ) scaffold as a bridging scaffold in a rabbit model of acute rotator cuff tendon defect. Study Design: Controlled laboratory study. Methods: We fabricated a DUCWJ scaffold using a physicochemical decellularized method, evaluating changes in the umbilical cord Wharton jelly before and after decellularization. Scanning electron microscopy and biomechanical testing were performed to determine the microstructure and mechanical properties. We assessed cytocompatibility and cell regulatory behavior of the scaffold toward tendon stem/progenitor cells (TSPCs). A supraspinatus tendon defect was created in 54 New Zealand White rabbits, allocated to the DUCWJ scaffold repair group and the negative control group (without scaffold). Histology, reverse transcription polymerase chain reaction, and biomechanical tensile strength were assessed at 4, 8, and 12 weeks postoperatively. Results: Decellularization completely removed cells from the umbilical cord Wharton jelly, retained a considerable amount of glycosaminoglycan and collagen, and preserved the microstructure and tensile strength. The DUCWJ scaffold facilitated migration and proliferation of TSPCs in vitro. Tendon-related gene expression revealed that the DUCWJ scaffold could maintain the tenocyte phenotype of TSPCs. In the in vivo study, the DUCWJ scaffold improved tendon healing and enhanced the biomechanical strength of repaired tendons. Histological evaluation scores of the DUCWJ group were significantly higher than those of the negative control at 4, 8, and 12 weeks after surgery ( P < .05). In repaired tendon tissues, reverse transcription polymerase chain reaction findings revealed that the DUCWJ scaffold stimulated tendon development and maturation. Furthermore, an overall increase in ultimate load and tensile modulus was noted over time; the DUCWJ group presented better results than the negative control group ( P < .05). Conclusion: The DUCWJ scaffold has an excellent 3-dimensional porous structure, good biocompatibility, and fundamental biomechanical characteristics, and it promotes migration, attachment, and proliferation of TSPCs. The in vivo animal study demonstrated that the DUCWJ scaffold has potential for tendon regeneration in an acute rotator cuff tendon defect model Clinical Relevance: DUCWJ scaffolds have potential as a regenerative material to augment rotator cuff healing in the clinical setting.