Development of pan-betacoronavirus vaccines

项目摘要/摘要 严重急性呼吸综合征冠状病毒2型(SARS-CoV-2)，一种新的冠状病毒 2019年，导致了目前的全球大流行。SARS-CoV-2病毒属于沙门氏菌亚属病毒。 贝塔冠状病毒属，由两种与SARS-CoV-2密切相关的病毒(SARS-CoV-1和SARS-CoV-1)组成的属 中东呼吸综合征冠状病毒(MERS-CoV)在过去17年里跨越了对人类的物种障碍。这些冠状病毒有 通过动物水库的人畜共患传播进入人类，突显了 未来的溢出效应。因此，制定能够缓解未来疫情爆发的干预策略 冠状病毒是至关重要的。为了应对未来的冠状病毒(Cov)大流行，生产疫苗是可取的。 能够诱导针对不同冠状病毒的中和抗体(NAB)反应。目前有两个主要的 开发基于预防疫苗的冠状病毒策略面临的挑战：1)冠状病毒尖峰的识别 用于疫苗靶向的广谱中和抗体(BNab)位点；以及2)疫苗策略的发展 这可以重复地诱导持久和保护性的bNab反应，以对抗广泛的冠状病毒。在……里面 在这次R01拨款申请中，我们将通过采用基于bNab表位的方法来解决这些知识差距 合理的疫苗设计方法，以开发免疫原和免疫策略，可以 冠状病毒疫苗接种保护性bNab反应。该项目由三个目标组成：目标#1将设计小说 使用合理的反向疫苗工程方法靶向疫苗免疫原的Spike S2干细胞bNab位点。 利用冠状病毒S_2茎螺旋bNAbs及其UCA，我们将设计基于冠状病毒S_2茎多肽的纳米颗粒， 以S蛋白三聚体为靶点的合理构建的S2bNab种系免疫原及其多聚体 能在体内高效激活靶向保守的S2干区的B细胞前体的纳米粒版本 穿过β冠状病毒尖峰。Aim#2将迭代评估和优化Prime Boost免疫策略 合适的临床前动物模型来开发疫苗方案，可以重复地诱导持久和 针对不同β冠状病毒的保护性bNab反应。我们将评估疫苗的体内保护效果- 在适当的病毒攻击模型中诱导bNab应答。Aim#3将产生尖峰S2茎螺旋bNab 利用合理的抗体工程方法，开发针对β冠状病毒的“超级抗体”。这个 这项R01拨款提案的总体目标是合理设计新的候选疫苗免疫原，开发 强大的疫苗接种策略，可以诱导持久的保护性bNab对广泛的β- 冠状病毒和开发“超级抗体”分子有望成为广泛的冠状病毒干预策略 以减轻令人担忧的SARS-CoV-2变种和新出现的冠状病毒，作为大流行防备的一部分。

PROJECT SUMMARY/ABSTRACT Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel coronavirus identified at the end of 2019, has led to the current global pandemic. The SARS-CoV-2 virus belongs to the subgenus sarbecovirus of the genus betacoronavirus, the genus from which two SARS-CoV-2 closely related viruses (SARS-CoV-1 and MERS-CoV) have crossed the species barrier to humans in the past 17 years. These coronaviruses have crossed into humans through zoonotic transmissions from animal reservoirs highlighting a potential threat for future spillovers. Therefore, development of intervention strategies that can mitigate outbreaks of future coronaviruses is critical. To prepare for future coronavirus (CoV) pandemics, it is desirable to generate vaccines capable of eliciting neutralizing antibody (nAb) responses against diverse CoVs. Currently there are two major challenges to develop prophylactic vaccine-based strategies against coronaviruses; 1) identification of CoV spike broadly neutralizing antibody (bnAb) sites for vaccine targeting; and 2) the development of vaccine strategies that can reproducibly induce durable and protective bnAb responses against a broad range of coronaviruses. In this R01 grant application, we will squarely address these knowledge gaps by employing a bnAb epitope based rational vaccine design approach to develop immunogens and immunization strategies that can induce coronavirus protective bnAb responses by vaccination. The project consists of 3 aims: Aim #1 will design novel spike S2 stem bnAb site targeting vaccine immunogens using a rational reverse vaccine engineering approach. Using CoV spike S2 stem helix bnAbs and their UCAs we will design, CoV S2 stem peptide-based nanoparticles, rationally engineered S2 bnAb germline-targeting S-protein trimer immunogens and their multimerized nanoparticle versions that can efficiently in vivo activate B cell precursors targeting the S2 stem region conserved across β-CoV spikes. Aim #2 will iteratively evaluate and optimize prime boost immunization strategies in appropriate pre-clinical animal models to develop vaccine protocols that can reproducibly induce durable and protective bnAb responses against diverse β-CoVs. We will assess the in vivo protective efficacy of the vaccine- induced bnAb responses in appropriate virus challenge models. Aim #3 will generate spike S2 stem helix bnAb based “super antibodies” against β-coronaviruses by utilizing rational antibody engineering approaches. The overall goal of this R01 grant proposal is to rationally design novel vaccine immunogen candidates, develop robust vaccination strategies that can induce durable protective bnAb responses against a broad range of β- coronaviruses and develop “super antibody” molecules promising for broad coronaviruses intervention strategies to mitigate SARS-CoV-2 variants of concern and emerging coronaviruses as part of pandemic preparedness.