Injectable Polypeptide‐Protein Hydrogels for Promoting Infected Wound Healing

TLDR

Protein is widely used in tissue engineering for its biocompatibility, yet natural proteins lack active functions such as vascularization, osteo‑induction, and neural differentiation, limiting their therapeutic potential. The study aims to create injectable polypeptide‑protein hydrogels that combine vascularization and antibacterial properties to promote healing of infected wounds. These hydrogels are fabricated by cross‑linking bovine serum albumin‑based polypeptides with silver ions, where Ag⁺ provides a sterile, antibacterial microenvironment and the K₂(SL)₆K₂(KK) polypeptide induces vascularization. In vivo experiments show the hydrogel enhances collagen deposition and vascularization, accelerates new tissue formation, and stimulates hair follicle regeneration, indicating its promise for infected wound treatment.

Abstract

Abstract Protein is the key composition of all tissues, which has also been widely used in tissue engineering due to its superior biocompatibility and low immunogenicity. However, natural protein usually lacks active functions such as vascularization, osteo‐induction, and neural differentiation, which limits its further applications as a functional biomaterial. Here, based on the mimetic extracellular matrix feature of bovine serum albumin, injectable polypeptide‐protein hydrogels with vascularization and antibacterial abilities are constructed successfully via coordinative cross‐linking of sulfydryl groups with silver ions (Ag+) for the regeneration of infected wound. In this protein hydrogel system, (Ag+), acting as crosslinkers, can not only provide a sterile microenvironment and a strong and robust antibacterial ability but also introduce K 2 (SL) 6 K 2 (KK) polypeptide, which endows the hydrogel with vascularization behavior. Furthermore, the in vivo data show that the polypeptide‐protein hydrogel has a considerable collagen deposition and vascularization abilities in the early stage of wound healing, resulting in rapid new tissue regeneration featured with newly appeared hair follicles. Altogether, this newly developed multifunctional 3D polypeptide‐protein hydrogel with vascularization, antibacterial properties, and hair follicle promotion can be a promising approach in biomedical fields such as infected wound healing.