Immunomodulatory Microneedle Patch for Cardiac Repair in Rodent and Porcine Models of Myocardial Infarction.

This study introduces a hyaluronic acid hydrogel-based microneedle patch embedded with IL-4-loaded PLGA microparticles. This highly biodegradable cardiac patch is for localized immunomodulation and cardiac repair following acute myocardial infarction (MI). This patch enables sustained IL-4 release, thereby fostering a macrophage-mediated pro-reparative microenvironment that promotes cardiomyocyte re-entry into the cell cycle and attenuates endothelial inflammatory signaling. In both rat and porcine MI models, this treatment significantly improved cardiac function and preserved myocardial structure. These findings highlight the translational potential of this patch as a therapeutic strategy for heart repair during the acute phase of MI.