Adenoviral Vector-based Pandemic Influenza Vaccine

项目摘要 H5、H7和H9亚型的低致病性和高致病性禽流感（HPAI）病毒的能力， 反复感染人类揭示了它们的人畜共患病性质和大流行潜力。此外，季节性流感 病毒（H1N1、H3 N2和流感B）继续演变并在全世界范围内构成重大的公共卫生威胁。 虽然可以针对个别流感病毒株制备候选疫苗病毒，但制备候选疫苗病毒是不切实际的。 为每一种潜在的大流行病毒储备大量疫苗。发展一个普遍的 流感疫苗对于制定更好的策略来对抗季节性流感以及 潜在的大流行性流感病毒。 我们研制了一种新的复制缺陷型3型牛腺病毒（BAd 3）疫苗 平台，其优于目前可获得的用于提供异源流感病毒的Ad载体系统 保护与剂量节省，并且不受预先存在的人Ad载体免疫力的影响。最近我们 已经揭示了BAd疫苗平台诱导免疫原的显著更高的表达水平 以及先天性和适应性免疫相关因子。我们还 鉴定了22个氨基酸残基的自噬诱导肽（AIP）C5（AIP-C5），其来自于 M.结核病增强小鼠对H7N9流感病毒NP的强大T细胞免疫应答， 通过广告载体传递。它提供了完全的保护（免于疾病，死亡或肺部病毒滴度）， H1N1、H3 N2、H5 N2、H7N9和H9 N2流感病毒。用表达Ad的Ad载体免疫小鼠 H5 N1 M2 e-HA 2 [与血凝素（HA）的茎部分（HA 2）连接的基质2的胞外结构域， HA信号肽和GCN 4亮氨酸拉链三聚化结构域]导致肺内 用H5 N1病毒攻击后的病毒滴度。 这一建议是基于这样的假设，即异亚型细胞介导的免疫（CMI） 针对NP的免疫应答和交叉反应性（不一定是交叉中和性）体液免疫应答 当与AIP-C5一起表达并通过载体递送时，针对NP或其他保守结构域（M2 e-HA 2） BAd疫苗平台，将提供广泛的保护，防止潜在的大流行H5，H7或H9禽流感 病毒以及季节性H1、H3和流感B病毒。该提案的目的是：（一）调查 新型抗原设计和疫苗递送平台在小鼠模型中免疫原性和保护效力 开发通用流感疫苗（目标1）; ii）确定 两种选定的雪貂通用流感疫苗配方（目标2）;以及iii）监测病毒传播 从接种疫苗的动物到未接种疫苗的动物，记忆B和T细胞应答的质量， 保护性免疫和病媒免疫，以及与疫苗相关的潜在增强呼吸道疾病（目标3）， 利用最先进的技术。

PROJECT SUMMARY The ability of both low and highly pathogenic avian influenza (HPAI) viruses of H5, H7, and H9 subtypes to repeatedly infect humans reveals their zoonotic nature and pandemic potential. Besides, the seasonal influenza viruses (H1N1, H3N2 & influenza B) continue to evolve and pose significant public health threats worldwide. While candidate vaccine viruses can be made for individual influenza strains, it is impractical to prepare significant vaccine stocks for each of the potentially pandemic viruses. The significance of developing a universal influenza vaccine is of utmost importance for developing a better strategy for combatting seasonal as well as potential pandemic influenza viruses. We have developed a novel replication-defective bovine adenovirus (Ad) type 3 (BAd3)-based vaccine platform, which is better than the currently available Ad vector systems for providing heterologous influenza protection with dose sparing and is not impacted by the pre-existing human Ad vector immunity. Recently, we have revealed that the BAd vaccine platform induces significantly higher expression levels of the immunogen and innate and adaptive immunity-related factors compared to that of human Ad vectors in mice. We have also identified a 22 amino acid residues Autophagy-Inducing Peptide (AIP) C5 (AIP-C5) from the CFP10 protein of M. tuberculosis that enhances robust T cell immune responses in mice to NP of H7N9 influenza virus when delivered through an Ad vector. It conferred complete protection (from disease, death, or lung viral titers) against H1N1, H3N2, H5N2, H7N9, and H9N2 influenza viruses. Immunization of mice with an Ad vector expressing H5N1 M2e-HA2 [the extracellular domain of matrix 2 linked to the stem portion (HA2) of hemagglutinin (HA) with the HA signal peptide and the GCN4 leucine zipper trimerization domain] led to a significant reduction in lung viral titers following challenge with an H5N1 virus. This proposal is based on the hypothesis that a combination of heterosubtypic cell-mediated immune (CMI) responses against NP and the cross-reactive (not necessarily cross-neutralizing) humoral immune responses against NP or other conserved domains (M2e-HA2), when expressed with AIP-C5 and delivered through the BAd vaccine platform, will provide broad protection against potential pandemic H5, H7, or H9 avian influenza viruses as well as seasonal H1, H3, and influenza B viruses. The aims of this proposal are: i) To investigate immunogenicity and protective efficacy of novel antigen design and vaccine delivery platform in a mouse model for developing universal influenza vaccines (Aim 1); ii) To ascertain immunogenicity and protective efficacy of two selected universal influenza vaccine formulations in ferrets (Aim 2); and iii) To monitor virus transmission from the vaccinated to non-vaccinated animals, the quality of memory B and T cell responses, the durability of protective and vector immunity, and potential vaccine-associated enhancement of respiratory disease (Aim 3), utilizing the state-of-the-art technologies.