On Designing Magnetic Vectors for DNA Vaccine Delivery

F.N. Al-Deen, C. Selomulya, C. Ma, S.D. Xiang, Y.Y. Kong, R. Coppel, M. Plebanski
Monash University, AU

Keywords: SPIONs, DNA vaccine, dendritic cells, malaria


Traditional protein-based malaria vaccines elicit only antibody-mediated (humoral) immune responses and are often expensive due to their processing requirements. DNA vaccine has emerged as an alternative strategy due to its low manufacturing costs and ability to induce both humoral and cellular immune responses against antigens encoded recombinant DNA. Effective delivery of DNA vaccines is crucial to ensure their efficacy, while non-viral polymeric DNA vaccine carriers are likely to be more immunogenic if they can also be efficiently taken up by potent antigen-presenting cells (APCs) such as dendritic cells (DCs). We reported how magnetofection can be used to enhance the delivery of a malaria DNA vaccine encoding Plasmodium yoelii merozoite surface protein, MSP119 (VR1020-PyMSP119). The magnetic vectors also showed adjuvant activity that encouraged DC maturation, while the application of external magnetic field improved gene delivery to DCs at low DNA doses, and also up-regulation of DC maturation markers. This knowledge is important for the design of DNA gene delivery tool to somatic cells such as DCs for potent immune activation for other diseases besides malaria, with studies currently underway to investigate the detailed uptake mechanisms and also specific type of DCs receptor of this gene delivery system.