Intranasal immunization with O-2′-Hydroxypropyl trimethyl ammonium chloride chitosan nanoparticles loaded with Newcastle disease virus DNA vaccine enhances mucosal immune response in chickens
Kai Zhao, Beini Sun, Ci Shi, Yanwei Sun, Zheng Jin, Gaowei Hu
Abstract
BACKGROUND: There has been a great interest in developing strategies for enhancing antigen delivery to the mucosal immune system as well as identifying mucosal active immunostimulating agents. To elevate the potential of O-2'-Hydroxypropyl trimethyl ammonium chloride chitosan (O-2'-HACC) as an adjuvant and mucosal immune delivery carrier for DNA vaccine, we prepared the O-2'-HACC loaded with Newcastle disease virus (NDV) F gene plasmid DNA and C3d6 molecular adjuvant (O-2'-HACC/pFDNA microparticles). RESULTS: The O-2'-HACC/pFDNA exhibited a regular spherical morphology with a particle size of 202.3 ± 0.52 nm, a zeta potential of 50.8 ± 8.21 mV, encapsulation efficiency of 90.74 ± 1.10%, and a 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 higher levels of IL-2, IL-4, IFN-γ, CD4+, and CD8 + T lymphocytes compared with the NDV commercial live attenuated 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 compared with the intramuscular delivery. CONCLUSIONS: Collectively, our findings indicated that the O-2'-HACC could be used as a vaccine adjuvant and delivery system for mucosal immunity and have an immense application promise.