Alternative approaches for NALT-based immunity to respiratory pathogens

摘要 鼻咽道是使人衰弱和潜在致命病原体的主要入口 包括炭疽杆菌和流感病毒。一种能促进抗体产生的粘多糖疫苗， 粘膜组织中的细胞毒性T细胞反应，除了一般的血流，保护更多的 比传统的注射疫苗更有效地对抗呼吸道病原体。因此需要 用于安全的粘膜佐剂和疫苗输送系统。以前这项赠款的工作集中在 将小鼠鼻相关淋巴网状组织（NALT）定义为免疫诱导位点， 针对鼻咽道的反应。我们使用霍乱毒素并开发了新的衍生物 缺乏ADP核糖基转移酶活性以避免该肠毒素佐剂的反应原性。 此外，我们还评估了炭疽毒素对小鼠NALT的作用。这些研究还 包括炭疽保护性抗原的抗体（Abs）的特性， 保护粘膜组织的潜力。共有五个原始的具体目标是成功的 处理。在我们的研究过程中，一个主要的和意想不到的发现是， 将炭疽芽孢杆菌保护性抗原与cAMP诱导性抗原的突变体一起共施用， 炭疽杆菌水肿因子增强粘膜和全身免疫力， 分子。此外，我们发现水肿毒素（EdTx或保护性抗原加水肿） 因子）衍生物增强了对共同施用的无关抗原的粘膜和全身免疫 如重组鼠疫耶尔森氏菌F1-V抗原。与神经节苷脂结合肠毒素霍乱不同 毒素，EdTx或其衍生物在鼻应用后都不靶向中枢神经系统组织。在 这次更新补助金，我们将解决的总体假设，舌下应用EdTx 衍生物将诱导基于NALT的免疫力，并保护免受呼吸道病原体的侵害， 副作用通常与鼻内应用肠毒素有关。一个人要确立的具体目标 与保护性抗原（PA）共同施用的水肿因子衍生物的佐剂活性， 舌下途径，以增强对炭疽毒素成分的免疫力。具体目标二将 表征通过舌下免疫提供的对呼吸道病毒感染的保护性免疫， EdTx衍生物作为佐剂。具体目标三的研究将确定 舌下免疫后分泌型IgA（SIgA）Ab的产生和粘膜免疫 EdTx衍生物。最后，具体目标四将确定诱导的分子信号， 通过EdTx衍生物作为舌下佐剂的SIgA应答。这笔资金将解开 EdTx衍生物通过其充当舌下疫苗的佐剂并诱导基于NALT的免疫。 我们还将验证一种新的粘膜疫苗递送途径，以及新的基于PA的粘膜疫苗。 用于诱导针对呼吸道病原体的免疫的佐剂。

Abstract The nasopharyngeal tract is a major portal entry of debilitating and potentially lethal pathogens including Bacillus anthracis and influenza virus. Mucosal vaccines capable of promoting antibody and cytotoxic T cell responses in mucosal tissues, in addition to the general bloodstream, protect more effectively against respiratory pathogens than classical injected vaccines. Therefore, there is a need for safe mucosal adjuvants and vaccine delivery systems. Previous work on this grant focused at defining murine nasal-associated lymphoreticular tissues (NALT) as inductive sites for immune responses targeting the nasopharyngeal tract. We used cholera toxin and developed novel derivatives lacking ADP ribosyl transferase activity to circumvent the reactogenicity of this enterotoxin adjuvant. In addition, we have assessed the action of anthrax toxins on murine NALT. These studies have also included the characterization of antibodies (Abs) to anthrax protective antigens with special emphasis on the potential to protect mucosal tissues. A total of five original Specific Aims were successfully addressed. A major and unexpected finding during the course of our studies was the fact the nasal co-administration of Bacillus anthracis protective antigen together with a mutant of the cAMP-inducing Bacillus anthracis edema factor enhanced mucosal and systemic immunity against these two molecules. Furthermore, we found that the edema toxin (EdTx or protective antigen plus edema factor) derivative enhanced mucosal and systemic immunity to co-administered unrelated antigens such as recombinant Yersinia pestis F1-V antigen. Unlike the ganglioside-binding enterotoxin cholera toxin, neither EdTx nor its derivatives target central nervous system tissues after nasal application. In this renewal grant, we will address the overall hypothesis that sublingual application of EdTx derivatives will induce NALT-based immunity and protect against respiratory pathogens, without the adverse effects often associated with nasal application of enterotoxins. Specific aim one will establish the adjuvant activity of edema factor derivatives co-administered with protective antigen (PA) via the sublingual route for enhanced immunity to anthrax toxin components. Specific aim two will characterize protective immunity to respiratory viral infection afforded by sublingual immunization with EdTx derivatives as adjuvant. Studies in specific aim three will identify inductive sites for the generation of secretory IgA (SIgA) Abs and mucosal immunity after sublingual immunization with EdTx-derivatives. Finally, specific aim four will determine molecular signals underlying the induction of SIgA responses by EdTx-derivatives as sublingual adjuvant. This grant will unravel the mechanisms by which EdTx derivatives act as adjuvant for sublingual vaccines and induce NALT-based immunity. We will also validate a new route for mucosal vaccine delivery, as well as new PA-based mucosal adjuvant(s) for the induction of immunity against respiratory pathogens.