Bioengineered Skeletal Muscle Construct Using A Cell-Seeded Decellularized Diaphragm Muscle Scaffolding System For Pelvic Muscle Regeneration.

Pelvic floor muscle injury often leads to dysfunction of the entire pelvic urogenital system, negatively impacting the patient's quality of life. Current treatment options include autologous muscle transfer and biomaterial-based meshes and slings; however, adequately restoring muscle function remains a significant challenge. With advances in skeletal muscle tissue engineering, bioengineered skeletal muscle constructs have emerged as promising therapeutic solutions for treating various types of muscle injuries. Recently, these strategies have been expanded to address injuries involving pelvic musculature. In this study, we developed a bioengineered skeletal muscle construct by seeding human muscle progenitor cells (hMPCs) onto a decellularized skeletal muscle scaffold to regenerate damaged pelvic muscle tissues. Allogeneic decellularized diaphragm muscle tissue was employed as a biological scaffold due to its structural and mechanical similarities to native pelvic muscle tissues. We demonstrated that the decellularized diaphragm retained aligned skeletal muscle matrix microstructures and preserved mechanical properties. hMPCs seeded on the decellularized scaffold remained viable and differentiated into aligned muscle fibers. The feasibility of the bioengineered muscle construct was investigated in a rat model of extensive pelvic muscle injury. Our in vivo results demonstrated that the implanted construct supported the formation of new skeletal muscle tissue with vascular and neural integration and improved recovery of muscle weight and function. To our knowledge, this is the first approach using decellularized diaphragm muscle tissue matrices as a biologic scaffold for pelvic muscle repair. With further advances, this approach may offer an alternative strategy for repairing pelvic muscle injuries. STATEMENT OF SIGNIFICANCE: Pelvic floor muscle injury significantly impairs quality of life, yet current mesh- and sling-based treatments are limited by poor structural and biological integration. Here, we developed a bioengineered skeletal muscle construct using human muscle progenitor cells seeded onto a decellularized diaphragm scaffold, given its biomimetic architecture and mechanical properties that closely resemble native pelvic floor muscle. In a rat model of pelvic floor injury, this construct promoted muscle regeneration, vascularization, and neural integration while improving muscle mass and function. To our knowledge, this is the first use of decellularized diaphragm tissue for pelvic muscle reconstruction. This approach may provide a promising strategy for supporting structural and functional muscle repair.