ANTI-CD40 DENDRITIC CELL-TARGETING VACCINE INDUCES PROTECTIVE IMMUNITY AGAINST NIPAH DISEASE

Nipah virus (NiV) is an emerging paramyxovirus which causes severe respiratory illness and deathly encephalitis in humans.Improving the ability of vaccines to induce strong, cellular, and humoral immune responses, remains the challenge to respond to Nipah and future Henipavirus infections rapidly and efficiently. A CD40.NiV vaccine has been engineered by fusing to the anti-CD40 monoclonal Ab the ectodomain of the Nipah G protein (Bangladesh strain) and immunogenic and conserved NiV F and N peptides. In mice, CD40.NiV promotes poly-antigenic T cell responses and significantly improves anti-NiV G IgG responses compared to the non-targeted NiV G immunogenic protein, in terms of avidity and neutralization potency. Immunogenicity was confirmed in the AGM (African Green Monkey) model, with induction of cross-neutralizing sera against circulating NiV strains and Hendra virus (HeV). Challenge experiment using NiV-B strain demonstrated the high protective efficacy of the vaccine with 100% survival in vaccinated group as compared to 100% lethality in controls. Surviving animals did not exhibit NiV viral replication in the blood, organs and swabs suggesting a sterilizing immunity conferred by the CD40.NiV vaccine. Taken together, results obtained with CD40.NiV vaccine are highly promising in terms of breadth and viral efficacy against NiV. we have performed RNA-sequencing analysis of peripheral whole blood at D0 (before prime), and one day post prime (PP, D1), before boost (D21) and one day post boost, (PB, D22) in 9 African green monkeys (AGM) vaccinated with CD40.NiV+Poly-ICLC at D0 and D21