Periodontal diseases are caused by microbial infection and the recruitment of destructive immune cells. Current therapies mainly deal with bacteria elimination, but the regeneration of periodontal tissues remains a challenge. Here we developed a modular microneedle (MN) patch that delivered both antibiotic and cytokines into the local gingival tissue to achieve immunomodulation and tissue regeneration. This MN patch included a quickly dissolvable gelatin membrane for an immediate release of tetracycline and biodegradable GelMA MNs that contained tetracycline-loaded poly(lactic-co-glycolic acid) nanoparticles and cytokine-loaded silica microparticles for a sustained release. Antibiotic release completely inhibited bacteria growth, and the release of IL-4 and TGF-β induced the repolarization of anti-inflammatory macrophages and the formation of regulatory T cells in vitro. In vivo delivery of MN patch into periodontal tissues suppressed proinflammatory factors and promoted pro-regenerative signals and tissue healing, which demonstrated the therapeutic potential of local immunomodulation for tissue regeneration.
Keywords: Microneedles; anti-bacteria; anti-inflammatory; biomaterials; immunoengineering; local immunomodulation.