DENDRITIC CELL-TARGETED NANOPARTICLES FOR THE DELIVERY OF DNA AND PROTEIN VACCINES

• Author / Creator

  Raghuwanshi,Dharmendra

• Dendritic cells (DCs) play a central role in shaping antigen-specific immune response. Antibody-mediated antigen targeting to DC-specific surface receptors is a promising approach to enhance vaccine efficacy. The objective of this thesis was to develop DC-targeted nanoparticulate formulations for the delivery of DNA and protein antigen using a novel strategy. The approach involved use of a two-component DC targeted delivery system for enhanced immune response. One component consisting of a recombinant bifunctional fusion protein (bfFp) was used for DC targeting, whereas, the other component made of biotinylated nanoparticles encapsulated antigen. For DNA vaccines, two strategies were adapted. In the first strategy, bfFp functionalized biotinylated chitosan nanoparticles containing DNA-encoding for nucleocapsid (N) of severe acute respiratory syndrome coronavirus (SARS-CoV) or hemagglutinin (HA) of avian influenza virus was used for nasal delivery. Immune response studies in mice showed that intranasal administration of targeted formulation along with DC maturation stimuli (anti-CD40 mAb) enhanced magnitude of mucosal, humoral and cellular immune responses. In the second strategy, a DNA (pDECN) vaccine encoding a fusion protein comprised of SARS CoV N antigen and anti-DEC-205 scFv was constructed. In vitro studies showed that expressed protein was able to bind with DCs. Vaccination of mice with pDECN-laoded chitosan nanoparticles induced significantly higher IgG and cytokine (IFN-γ and IL-2) response relative to SARS CoV N DNA. Coadministration of anti-CD40 antibody further improved efficacy of nanoencapsulated DNA formulations. For the delivery of a model antigen ovalbumin (OVA), biotinylated poly(D,L-lactic-co-glycolic acid) (PLGA) nanoparticles were formulated using biotin-PEG-PLGA polymer and were decorated with bfFp. In vitro uptake studies revealed one-fold higher uptake of targeted nanoparticles compared to non-targeted NPs. In vivo studies show targeted NPs in conjunction with anti-CD40 mAb enhanced OVA-specific IgG and IgG subclass responses. Splenocytes of these mice secreted significantly higher levels of IFN-γ and IL-2, indicating Th1 response. In conclusion, these results demonstrate that bfFp based DC targeting is a versatile approach and vaccine efficacy can be enhanced via non-invasive DC targeting. The two-component DC targeting approach can serve as a viable alternative to conventional antibody-targeted vaccines that also precludes any post-formulation modification of the antigen-loaded NPs.

• Subjects / Keywords

  • Nanoparticles
  • Vaccine
  • Dendritic cell targeting

• Graduation date

  Fall 2012

• Type of Item

  Thesis

• Degree

  Doctor of Philosophy

• DOI

  https://doi.org/10.7939/R3W07K

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.