Drug Delivery and Translational Research - Featured Article: June 2023
Read the featured article from the June 2023 issue! (this opens in a new tab)
Title: Sustained antigens delivery using composite microneedles for effective epicutaneous immunotherapy
Allergen-specific immunotherapy is an efficacious therapy for various allergic diseases such as food allergy (FA). However, frequent clinical visits and potential adverse effects often hinder patient compliance. Here, we proposed an implantable microneedle (MN) system composed of OVA (antigen)-loaded silk MNs and a dissolvable, flexible polyvinyl alcohol (PVA) pedestal. Once MNs are inserted into the skin, the PVA pedestal can quickly dissolve in the interstitial fluid of the excised skin and implant the OVA-loaded silk MN tips in dermal layer as a sustained antigen depot, thus inducing long-lasting immune response. After receiving 3 doses of MN-based immunotherapy, the immune response in OVA-sensitized mice was successfully suppressed, with no apparent side effects. Compared to conventional subcutaneous immunotherapy, MN immunotherapy ameliorated systemic anaphylaxis more effectively even at a lower dose, demonstrating the antigen dose-sparing potential of the proposed MNs. Moreover, due to the prolonged release effect of silk-PVA composite MNs, the frequency of immunotherapy can be significantly reduced. Overall, through prolonged skin exposure to antigen, this implantable designed MN may offer a new therapeutic strategy for FA treatment with significant improvements in efficacy and convenience.