Abstract
Background: There is a great interest to develop strategies for enhancing antigen delivery to mucosal immune system as well as to identify mucosal active immunostimulating agents. To elevate the potential of O -2′-Hydroxypropyl trimethyl ammonium chloride chitosan (O-2′-HACC) nanoparticles as adjuvant and mucosal immune delivery carrier for DNA vaccine, we prepared the O-2′-HACC nanoparticles loaded with Newcastle disease virus F gene plasmid DNA with C3d6 molecular adjuvant (O-2′-HACC/pFDNA). Results: The O-2′-HACC/pFDNA had regular spherical morphology with a particle size of 202.3±0.52 nm, zeta potential of 50.8±8.21 mV, encapsulation efficiency of 90.74±1.10 %, and loading capacity of 49.84±1.20 %. The plasmid DNA could be sustainably released from the O-2′-HACC/pFDNA after an initial burst release. Intranasal vaccination of chickens immunized with O-2′-HACC/pFDNA not only induced higher anti-NDV IgG and sIgA antibody titers, but also significantly promoted lymphocyte proliferation and produced the higher levels of IL-2, IL-4, IFN-γ, CD4+ and CD8+ T lymphocytes than the NDV commercial attenuated live vaccine. Intranasal delivery of the O-2′-HACC/pFDNA enhanced humoral, cellular and mucosal immune responses, and protected chickens from the infection of highly virulent NDV than intramuscular delivery. Conclusions: This study indicated that the O-2′-HACC nanoparticles could be used as vaccine adjuvant and delivery system for mucosal immunity and have an immense application promise.
Immune effect of a Newcastle disease virus DNA vaccine with IL-12 as a molecular adjuvant delivered by electroporation
