SilMA-stabilized micro-wavy PLCL vascular grafts for native-like nonlinear mechanics and vascular remodeling

Cardiovascular diseases remain a major cause of mortality, yet small-diameter vascular grafts (SDVGs) are still limited by thrombosis and pathological luminal remodeling caused in part by mechanical mismatch. Here, we developed electrospun poly(L-lactide-co-ε-caprolactone) (PLCL) grafts with a mechanically programmed micro-wavy architecture and artery-like nonlinear elasticity. A conformal methacrylated silk fibroin (SilMA) layer was photopolymerized onto the PLCL fibers to stabilize the programmed structure and improve the blood-contacting interface. The resulting graft preserved a porous architecture, achieved a compliance of 15.0 ± 1.8% per 100 mmHg, and maintained nonlinear mechanics during degradation. Fluid-structure interaction analysis showed improved diameter matching and local hemodynamic distributions closer to those of native arteries under pulsatile loading. SilMA modification also improved hemocompatibility by reducing clot formation and platelet adhesion. At 30 days, the final graft formulation remained patent and showed continuous endothelial coverage, organized α-SMA⁺ tissue formation, and a mild inflammatory response. These results demonstrate that interfacial photostabilization can integrate mechanical matching with organized vascular remodeling in biodegradable SDVGs.