Presenting Author: Renukaradhya Gourapura
, Professor at Ohio State Univ.
Abstract:
We developed whole inactivated SwIV H1N2 based mannose-chitosan nanoparticle (mChit-SwIV-NP) vaccine containing STING (stimulator of interferon gene) adjuvant ADU-S100, either both encapsulated (mChit-SwIV+S100-eNP) or surface adsorbed (mChit-SwIV+S100-sNP). Influenza-free nursery pigs were vaccinated intranasally twice at 3-weeks interval and challenged with the heterologous pandemic 2009 H1N1 virus. The infectious virus load was reduced by over 2 log10 in nasal passage of mChit-SwIV+S100-sP and 1.5 log10 in mChit-SwIV+S100-eNP vaccinates. Immunologically, increased specific IgG and sIgA responses with high avidity and virus neutralizing antibodies in the respiratory tract and serum of mChit-SwIV+S100-sNP vaccinates was observed. While frequency of activated IFNγ+ and IL-17A+ cytotoxic T lymphocytes and T-helper/memory cells in PBMCs and tracheobronchial lymph nodes mononuclear cells, and lymphocytes stimulation index in lymph nodes cells were increased in mChit-SwIV+S100-eNP vaccinates, higher than mChit-SwIV+S100-sNP and commercial SwIV vaccinated animals. In summary, intranasal mChit-SwIV+S100-sNP vaccine elicited cross-reactive antibody while mChit-SwIV+S100-eNP vaccine induced mucosal and systemic cell-mediated immune responses higher than commercial SwIV vaccinates. Suggesting that mannose-chitosan nanoparticle vaccine has a promise in mitigating SwIV infections and transmission in swine herds.