Enhanced immunogenicity and protection study of lipid modified protein vaccine candidates of Nontypeable Haemophilus influenzae

摘要： 在结合疫苗时代，不可分型流感嗜血杆菌（NTHi）已成为 急性中耳炎（AOM），复发性AOM，急性鼻窦炎和结膜炎的主要原因， 儿童和成人与慢性阻塞性肺疾病（COPD）急性加重 成年人了需要开发针对NTHi的疫苗。各种候选疫苗已经被 但是仍然需要增强NTHi的抗体和Th 17免疫应答 有助于预防鼻咽定植和感染的疫苗。在这个项目中，我们将 比较重组蛋白P6和OMP 26及其融合构建体在小鼠中的免疫原性。 在NTHi-AOM的小鼠共感染模型中，我们开发了它们的脂化和非脂化形式。 基于它们的不同功能选择两种蛋白质，并且考虑到P6是天然的。 脂化的和天然的OMP 26不诱导Th 17免疫，但已知其诱导Th 17免疫。我们将测试我们的 假设脂化蛋白抗原也引起更高的血液和粘膜抗体水平 Th 17免疫应答（通过Toll样受体2激活）。脂化 蛋白抗原将引起耳和鼻细菌负荷的更大减少， 抗NTHi的非脂化抗原。抗体介导的免疫反应的贡献和机制 将在婴儿和成年小鼠中比较TH 17介导的免疫对NTHi的保护作用， 以及在TLR 2敲除小鼠中使用脂质化、非脂质化和融合疫苗构建体 候选人P6和OMP 26。我们将测试脂化蛋白质是否产生更强的IL-17 A 来自鼻咽部记忆性Th 17细胞的反应，有助于中性粒细胞的运输， 与非脂化蛋白抗原相比，NTHi清除率提高。总体而言，拟议 这些研究将显著推进我们对重组免疫原性增强的理解， TLR-2依赖的脂化调节的蛋白质和分子机制 NTHi疫苗开发中的Th 17免疫。

Abstract: In the conjugate vaccine era, Nontypeable Haemophilus influenzae (NTHi) has become the leading cause of acute otitis media (AOM), recurrent AOM, acute sinusitis and conjunctivitis in children and adults and acute exacerbations of chronic obstructive pulmonary disease (COPD) in adults. There is need to develop a vaccine against NTHi. Various vaccine candidates have been explored but still there is need for enhancement of antibody and Th17 immunity response for NTHi vaccines that will help prevent nasopharyngeal colonization and infection. In this project we will compare immunogenicity of recombinant proteins P6 and OMP26 and their fusion constructs in their lipidated and non-lipidated form in a mouse coinfection model of NTHi-AOM, we developed. Two proteins were selected based on their different function and considering P6 is naturally lipidated and native OMP26 is not but is known to induce Th17 immunity. We will test our hypothesis that lipidated protein antigens elicit higher blood and mucosal antibody levels as well as Th17 immune response (via toll-like receptor 2 activation) than non lipidated proteins. Lipidated protein antigens will elicit greater reduction in ear and nasal bacterial loads compared to nonlipidated antigens against NTHi. The contribution and mechanism of antibody mediated and TH17-mediated immunity in protection against NTHi will be compared in infant and adult mice as well as in TLR2-knock out mice using lipidated, nonlipidated and fusion constructs of vaccine candidates P6 and OMP26. We will test whether lipidated proteins produce a more robust IL-17A response from memory Th17 cells in the nasopharynx that helps traffic neutrophils and show enhanced NTHi clearance compared to nonlipidated protein antigens. Overall, the proposed studies will significantly advance our understanding of enhanced immunogenicity of recombinant proteins and molecular mechanisms underlying the lipidation regulation of TLR-2 dependent Th17- immunity in NTHi vaccine development.