Bacterial infection often leads to inflammatory responses and delays wound healing. Chitosan (CS)-based composite hydrogels can hold desirable mechanical properties and maintain excellent antibacterial abilities, and thus may be promising as wound dressings. Although CS-based hydrogels have been widely studied on the antibacterial and wound-healing abilities, their immunomodulatory abilities were rarely evaluated. Herein, we developed a multifunctional CS/Poly[2-(methacryloyloxy)ethyl] trimethyl ammonium chloride (PMETAC) hydrogel. In vitro, this hydrogel exhibited self-healing ability and excellent biocompatibility, promoted macrophage polarization towards M2 phenotype, and showed desirable antibacterial activity. In vivo, this hydrogel accelerated the wound regeneration process by reducing bacterial burden, increasing collagen deposition, stimulating angiogenesis, promoting macrophage polarization to M2 direction, and shifting the balance of T helper type 17 (Th17) cells towards anti-inflammatory regulatory T (Treg) cells. This work revealed the potential immunomodulatory effect of CS-based wound dressings and thus may provide a novel target for developing efficient wound healing tools.

细菌感染通常会导致炎症反应并延迟伤口愈合。基于壳聚糖 (CS) 的复合水凝胶可以保持理想的机械性能并保持出色的抗菌能力，因此有望用作伤口敷料。尽管基于 CS 的水凝胶在抗菌和伤口愈合能力方面得到了广泛研究，但很少评估其免疫调节能力。在此，我们开发了一种多功能 CS/聚 [2-(甲基丙烯酰氧基)乙基] 三甲基氯化铵 (PMETAC) 水凝胶。在体外，这种水凝胶表现出自我修复能力和优异的生物相容性，促进巨噬细胞向 M2 表型极化，并显示出理想的抗菌活性。体内, 这种水凝胶通过减少细菌负担、增加胶原蛋白沉积、刺激血管生成、促进巨噬细胞极化向 M2 方向以及将 17 型辅助性 T (Th17) 细胞的平衡转向抗炎调节性 T (Treg) 细胞来加速伤口再生过程. 这项工作揭示了基于 CS 的伤口敷料的潜在免疫调节作用，因此可能为开发有效的伤口愈合工具提供新的目标。