Proangiogenic peptide nanofiber hydrogel/3D printed scaffold for dermal regeneration

Abstract

Dermal substitutes have been widely used as therapeutic options in skin damage to regenerate the skin. Rapid vascularization of a dermal substitute can provide channels for nutritional support, excretion and create an interventional pathway for the immune system during the early wound healing stages. Therefore it is important to evaluate the vascularization property of dermal substitutes in the process of dermal reconstruction. In this study, a proangiogenic self-assembling peptide nanofiber hydrogel (SLg) was synthesized and combined with UV-cured gelatin (GelMA) to prepare a series of three-dimensional (3D) printed scaffolds. Interpenetrating polymer networks (IPNs) comprising interwoven gelatin and peptide were constructed during 3D printing process, resulting in advancement in absorbency and elasticity. Moreover, the 3D printed GelMA/SLg scaffolds exhibited controlled porosity, pore size and connected pore properties. These properties provided the appropriate microenvironment for cellular migration, proliferation and were conducive for the growth of blood vessels leading to early angiogenesis. An in vivo study found that 3D printed GelMA/SLg scaffolds containing 20% peptide hydrogel exhibited the best collagenous fibrous structure, fastest repair cycles in revascularization and dermal regeneration. These results imply that the proangiogenic scaffold promotes early rapid vascularization and tissue healing, and is a promising therapeutic option for high-quality regenerative repair of skin damage.