Local Immunomodulation Using an Adhesive Hydrogel Loaded with miRNA‐Laden Nanoparticles Promotes Wound Healing

TLDR

Chronic wounds exhibit impaired healing and uncontrolled inflammation that can lead to infection, while miR‑223 promotes macrophage M2 polarization to aid repair, yet delivering miRNAs locally remains difficult due to instability. The study developed adhesive hydrogels loaded with hyaluronic acid nanoparticles carrying miR‑223* to modulate macrophage polarization during wound healing. In vivo, the hydrogels adhered to acute excisional wounds and released miR‑223*, enabling local delivery of the microRNA. The treatment increased anti‑inflammatory Arg‑1, reduced TNF‑α, IL‑1β, and IL‑6 in macrophages, and in vivo promoted uniform vascularized skin formation through M2 polarization, accelerating wound healing.

Abstract

Abstract Chronic wounds are characterized by impaired healing and uncontrolled inflammation, which compromise the protective role of the immune system and may lead to bacterial infection. Upregulation of miR‐223 microRNAs (miRNAs) shows driving of the polarization of macrophages toward the anti‐inflammatory (M2) phenotype, which could aid in the acceleration of wound healing. However, local‐targeted delivery of microRNAs is still challenging, due to their low stability. Here, adhesive hydrogels containing miR‐223 5p mimic (miR‐223*) loaded hyaluronic acid nanoparticles are developed to control tissue macrophages polarization during wound healing processes. In vitro upregulation of miR‐223* in J774A.1 macrophages demonstrates increased expression of the anti‐inflammatory gene Arg‐1 and a decrease in proinflammatory markers, including TNF‐α, IL‐1β, and IL‐6. The therapeutic potential of miR‐223* loaded adhesive hydrogels is also evaluated in vivo. The adhesive hydrogels could adhere to and cover the wounds during the healing process in an acute excisional wound model. Histological evaluation and quantitative polymerase chain reaction (qPCR) analysis show that local delivery of miR‐223* efficiently promotes the formation of uniform vascularized skin at the wound site, which is mainly due to the polarization of macrophages to the M2 phenotype. Overall, this study demonstrates the potential of nanoparticle‐laden hydrogels conveying miRNA‐223* to accelerate wound healing.