Universal T cell targeted influenza vaccine

摘要 流感每年在世界范围内造成显著的发病率和死亡率，并导致严重的 当新的毒株演变成以前没有在人类中传播的病毒时，就会发生大流行。高病毒变异率 这就需要每年根据流行毒株的流行情况生产新的疫苗。这些 重新配制的流感疫苗并不总是具有保护作用；疫苗效力(VE)各不相同 根据疫苗毒株与流行毒株的匹配程度，在过去10年中下降了10%至60%。 目前迫切需要能够产生更强交叉保护免疫力的流感疫苗，这种需求尚未得到满足。我们 建议利用广泛反应的流感特异性T细胞表位的免疫原性潜力来产生 具有普遍意义的疫苗。我们之前由R21资助的工作已经提供了原则证明 先进的免疫信息学工具可以有效地识别高度保守的甲型流感表位， 包括混杂的CD4+T细胞表位和人类白细胞抗原A2限制的CD8+T细胞表位，即 具有免疫原性，可诱导保护性免疫。此外，我们已经令人信服地证明 旨在刺激人类T细胞反应的T细胞疫苗可以诱导异型保护 豁免权。我们现在建议扩展我们的R21研究，以更全面地评估混杂的CD4+T细胞 确认这些表位可以在95%的人类中激发有效的CD4+T细胞反应 表达多种人类白细胞抗原II类等位基因。我们还将确定相关的CD8+T细胞表位， 额外的非人类白细胞抗原A2 I类超类型，以获得广泛人群覆盖的足够表位(&gt；95% 人类)。然后，我们将开发并比较多表位疫苗的免疫原性和保护效果。 使用几种最先进的疫苗输送平台，包括：重组的裸露DNA，纯化的蛋白质 混合了新型佐剂的新型腺病毒(Ad)疫苗旨在逃避先前存在的人类Ad 免疫和病毒样颗粒(VLP)包裹的RNA疫苗。疫苗将在体外进行测试，使用 人外周血单核细胞和体内用人源化小鼠表达转基因人类白细胞抗原。异型药效将是 对3种不同的甲型流感病毒株(H1N1、H3N1和H5N1)进行攻击后进行评估。拟议中的工作 可为流感疫苗开发提供变革性新产品和方向，重点 关于诱导广泛保护性T细胞反应的范式转换概念。

Abstract Influenza is responsible for significant morbidity and mortality worldwide every year and causes severe pandemics when new strains evolve that have not previously circulated in humans. The high viral mutation rate necessitates that new vaccines be generated based on the prevalence of circulating strains every year. These reformulated versions of influenza vaccines are not always protective; vaccine effectiveness (VE) has varied from 10 to 60% over the past 10 years based on how well vaccine strains are matched with circulating strains. There is an urgent unmet need for influenza vaccines that induce greater cross-protective immunity. We propose to harness the immunogenic potential of broadly reactive influenza-specific T cell epitopes to produce vaccines with universal significance. Our previous R21 funded work has provided proof-of-principle that advanced immunoinformatic tools can be used to efficiently identify highly conserved influenza A epitopes, including promiscuous CD4+ T cell epitopes and HLA-A2-restricted CD8+ T cell epitopes, that are immunogenic and can induce protective immunity. Furthermore, we have convincingly demonstrated that T cell-based vaccines designed to stimulate human T cell responses can induce heterotypic protective immunity. We now propose to extend our R21 studies to more fully evaluate promiscuous CD4+ T cell epitopes to confirm that these epitopes can elicit potent CD4+ T cell responses in >95% of all humans expressing diverse HLA class II alleles. We also will identify relevant CD8+ T cell epitopes restricted by additional non-HLA-A2 class I supertypes, to obtain sufficient epitopes for broad population coverage (>95% of humans). We then will develop and compare immunogenicity and protective efficacy of multi-epitope vaccines using several state-of-the art vaccine delivery platforms including: recombinant ‘naked’ DNA, purified proteins mixed with novel adjuvants, novel adenovirus (Ad) vaccines designed to evade preexisting human Ad immunity, and virus-like particle (VLP) encapsidated RNA vaccines. Vaccines will be tested in vitro using human PBMC and in vivo using humanized mice expressing transgenic HLA. Heterotypic efficacy will be evaluated upon challenge with 3 distinct influenza A strains (H1N1, H3N2, and H5N1). The proposed work can provide transformational new products and direction for influenza vaccine development, focusing on a paradigm-shifting concept of inducing broadly protective T cell responses.