A dual vaccine strategy against filovirus infection

项目描述（申请人提供）：该项目的重点是开发针对丝状病毒感染的有效疫苗，丝状病毒感染是高致死性出血热的病原体，可通过人与人之间的接触传播，因此具有很高的爆发流行的威胁。我们已经研究了针对病毒感染的VLP疫苗的开发，并且已经显示使用重组杆状病毒表达系统在昆虫细胞中产生的EBOV VLP具有高VLP产量，显示DC刺激活性并且诱导强的中和EBOV GP介导的病毒感染的抗体应答，表明此类VLP可以是安全且有效的疫苗，以诱导针对EBOV感染的保护性免疫。我们还发现，用DNA和VLP疫苗的混合物（DNA/VLP）进行免疫接种与用单独的任一种进行免疫接种相比诱导更高水平的抗体和细胞免疫应答。我们假设新型DNA/VLP疫苗将引发针对丝状病毒感染的强烈细胞和抗体应答，并且采用新的疫苗递送技术将进一步增强此类应答的诱导，目的是获得可以赋予针对丝状病毒感染的快速和持久保护的疫苗策略。具体目标1。提高DNA疫苗和VLP疫苗的免疫原性，以诱导针对泛丝状病毒感染的更有效和持久的保护性免疫。我们将探索不同的策略来修饰丝状病毒DNA和VLP疫苗，以增强其诱导抗体和T细胞应答的免疫原性以及其产量，并将确定有助于实现针对丝状病毒感染的持久保护的免疫应答。具体目标2。评价微针（MN）技术用于丝状病毒疫苗递送。我们将开发将丝状病毒DNA和VLP疫苗包封到生物可吸收MN中的技术，并研究包封疫苗的生物学特性、稳定性和免疫原性，并研究不同的几何设计和化学配方，以进一步改进MN疫苗递送技术，以实现更有效和可重复的疫苗包封，并提高疫苗稳定性。具体目标3。比较不同疫苗方法的保护效力，并确定针对丝状病毒感染的免疫相关性。我们将比较使用常规肌内注射以及新型MN疫苗递送技术的不同疫苗制剂诱导的免疫应答，并在小型实验室动物模型以及非人灵长类动物中评价其针对致死性丝状病毒攻毒的保护效力，并将确定对于实现针对丝状病毒感染的持久保护重要的免疫应答的相关性。这些结果将为GMP生产和人体试验选择最有效的候选疫苗策略奠定基础。这种疫苗策略的成功开发也可以很容易地应用于针对仍然缺乏有效疫苗的其他病毒性出血热的疫苗。

DESCRIPTION (provided by applicant): This project focuses on development of an effective vaccine for filovirus infection, which is an etiologic agent of highly lethal hemorrhagic fever and can be transmitted via person-to-person contact, thus posing a high threat of an epidemic outbreak. We have studied the development of VLP vaccines against virus infection, and have shown that EBOV VLPs produced in insect cells using the recombinant baculovirus expression system, which gives high VLP production yield, exhibit DC-stimulating activity and induce strong antibody responses that neutralize EBOV GP mediated virus infection, indicating that such VLPs could be safe and effective vaccines to induce protective immunity against EBOV infection. We also found that immunization with a mixture of DNA and VLP vaccines (DNA/VLP) induced higher levels of both antibody and cellular immune responses in comparison to immunization with either alone. We hypothesize that the novel DNA/VLP vaccine will elicit strong cellular and antibody responses against filovirus infection and that the employment of a new vaccine delivery technology will further augment induction of such responses, with the aim to obtain a vaccine strategy that can confer rapid and long lasting protection against filovirus infection. Specific Aim 1. To improve the immunogenicity of DNA and VLP vaccines for eliciting more potent and durable protective immunity against pan-filovirus infection. We will explore different strategies to modify filovirus DNA and VLP vaccines to enhance their immunogenicity for inducing both antibody and T cell responses as well as their production yield and will determine the immune responses that contribute to and are critical for achieving long lasting protection against filovirus infection. Specific Aim 2. To evaluate the microneedle (MN) technology for filovirus vaccine delivery. We will develop the technology to encapsulate filovirus DNA and VLP vaccines into bio-absorbable MNs and investigate the biological property, stability, and immunogenicity of encapsulated vaccines and investigate different geometrical designs and chemical formulations to further improve the MN vaccine delivery technology for achieving more efficient and reproducible vaccine encapsulation, and improved vaccine stability. Specific Aim 3. To compare the protective efficacy of different vaccine approaches and determine the immune correlates for protection against filovirus infection. We will compare immune responses induced by different vaccine formulations using both conventional intramuscular injection as well as the novel MN vaccine delivery technology and evaluate their protective efficacy against lethal filovirus challenge in small laboratory animal models as well as non-human primates and will determine the correlates of immune responses that are important for achieving long lasting protection against filovirus infection. The results will set the foundation for selection of the most effective candidate vaccine strategy for GMP production and human trials. The successful development of this vaccine strategy may also be readily applied to vaccines against other viral hemorrhagic fevers which still lack effective vaccines.