Microneedle-Mediated Transcutaneous Immunization: Potential in Nucleic Acid Vaccination.

Efforts aimed at exploring economical and efficient vaccination have taken center stage to combat frequent epidemics worldwide. Various vaccines have been developed for infectious diseases, among which nucleic acid vaccines have attracted much attention from researchers due to their design flexibility and wide application. However, the lack of an efficient delivery system considerably limits the clinical translation of nucleic acid vaccines. As mass vaccinations via syringes are limited by low patient compliance and high costs, microneedles (MNs), which can achieve painless, cost-effective, and efficient drug delivery, could provide an ideal vaccination strategy. The MNs can break through the stratum corneum barrier in the skin and deliver vaccines to the immune cell-rich epidermis and dermis. In addition, the feasibility of MN-mediated vaccination has been demonstrated in both preclinical and clinical studies and has tremendous potential for the delivery of nucleic acid vaccines. In this manuscript, we review the current status of research on MN vaccines. Moreover, we summarize the improvements of MN-mediated nucleic acid vaccination and discuss the challenges of its clinical translation in the future. This article is protected by copyright. All rights reserved.