On-Demand Local Immunomodulation via Epigenetic Control of Macrophages Using an Inflammation-Responsive Hydrogel for Accelerated Wound Healing

Effective resolution of inflammation contributes to favorable tissue regenerative therapeutic outcomes. However, fine coordination of local immunomodulation in a timely manner is limited because of the lack of strategies for controlling disease dynamics. We developed an inflammation-responsive hydrogel (IFRep gel) as an effective therapeutic strategy for on-demand epigenetic modulation against disease dynamics in wound healing. The IFRep gel is designed to control drug release by cathepsins according to the state of inflammation for active disease treatment. The gel loaded with an inhibitor of the epigenetic reader bromodomain (BRD)4 regulates the translocation of nuclear factor erythroid 2 to the nucleus, where it promotes antioxidant gene expression to reverse the inflammatory macrophage state in vitro. In addition, on-demand BRD inhibition using the responsive hydrogel accelerates wound healing by controlling the early inflammatory phase and keratinocyte activation in vivo. Our data demonstrate the clinical utility of using the IFRep gel as a promising strategy for improving therapeutic outcomes in inflammationassociated diseases.