Vascular collagen-based biomaterials for vascular Tissue engineering

Vascular Tissue Engineering:

Abstract

Backgrounnd:Cardiovascular diseases necessitate functional vascular substitutes, yet autologous grafts are often unavailable. Tissue engineering offers a promising alternative, with collagen as the primary extracellular matrix (ECM) component of native blood vessels emerging as a key biomaterial for vascular tissue engineering (VTE).

Aim:This review systematically examines the role of collagen-based biomaterials in VTE, covering biological rationale, scaffold fabrication strategies, preclinical outcomes, and translational challenges.

Result: Native vascular ECM, dominated by collagens type I, III, and IV, provides mechanical integrity and cell‑matrix interactions via integrins and discoidin domain receptors, which dictate endothelial and smooth muscle cell behavior. Various scaffold architectures are discussed, including collagen hydrogels that support capillary‑like network formation but lack mechanical strength, electrospun collagen‑synthetic blends that achieve clinically relevant burst pressures, crosslinked matrices (using EDC/NHS, genipin, or enzymatic methods) with enhanced durability, and decellularized vascular scaffolds that preserve native ECM architecture. Advanced biofabrication techniques particularly 3D bioprinting  and interpenetrating network hydrogels enable the creation of perfusable, cell‑responsive conduits. Functionalization with heparin, growth factors (VEGF, bFGF), or copper ions further confers antithrombotic and pro‑angiogenic properties. Preclinical large‑animal studies (sheep, canine) demonstrate patency rates >90% with evidence of endothelialization and neointima formation. However, clinical translation remains limited by residual thrombogenicity, intimal hyperplasia, sterilization compatibility, manufacturing scalability, and regulatory complexity.

Conclusion: Future directions include smart, environment‑responsive collagen materials that recruit endogenous cells and degrade in synchrony with new tissue formation. With continued interdisciplinary efforts, collagen‑based vascular grafts hold realistic potential to transform the surgical management of cardiovascular disease.