DNA-based vaccines: Advances, applications, and future prospects.

DNA-based vaccines represent a promising advancement in immunization strategies, offering a novel approach for preventing infectious diseases and treating various conditions, including cancers and autoimmune disorders. These vaccines utilize genetically engineered plasmid or viral vector DNA encoding antigens of interest, which, upon administration, are taken up by host cells to produce the antigen in situ. This endogenous antigen expression elicits both humoral and cellular immune responses, mimicking natural infection pathways. Compared to conventional vaccines, DNA vaccines offer several advantages: they are relatively easy to design and manufacture, relatively stable, and capable of inducing long-lasting immunity without the need for live pathogens. Additionally, their platform is highly adaptable, enabling rapid development against emerging pathogens. Despite their success in animal models and promising results in clinical trials for infectious diseases caused by viruses, such as Zika, HPV, and SARS-CoV-2, DNA vaccines have faced challenges in eliciting robust immunogenicity in humans. Recent innovations-including improved delivery technologies, adjuvant formulations, and optimized plasmid and viral vectors-are addressing these limitations. The approval of DNA vaccines for veterinary use and recent human applications, such as Adenovirus (Ad) DNA-based Ebola vaccines and plasmid DNA-based COVID-19 vaccine, ZyCoV-D, mark significant milestones. Continued research and technological refinement are expected to expand their utility in global health. Overall, DNA-based vaccines hold great potential as a next-generation platform for safe, effective, and rapid-response immunization against a broad spectrum of diseases.