Human Monoclonal Antibodies for Encephalitic Alphaviruses

总结： 东方马脑炎病毒（EEEV）是一种重新出现的蚊媒甲病毒，可引起一种使人衰弱的 人类的脑炎大约三分之一的EEEV感染病例死亡，许多幸存者 长期的神经衰弱问题该病毒维持在库利塞塔之间的地方流行循环中， 黑尾蚊和鸟类宿主，但可通过以下途径传播给人类和马： 一些伊蚊、Coquillettidia和库蚊属物种。这种感染在人类中并不常见，但其频率正在增加 近年来，可能继发于气候变化、病媒扩张和其他未定性因素。EEEV 由于通过气溶胶途径传播，也被视为潜在的生物恐怖主义威胁。尽管高致病性 由于病毒的性质，没有针对EEEV的特异性治疗或疫苗。该项目的主要目标是 确定了超强效中和人血白细胞的分子、遗传、免疫学和结构特征， 在体内对EEEV具有广泛活性的mAb。其他目标包括定义以下机制的相关性： 通过这些超强力的中和单克隆抗体的保护，并确定优化功能和递送至 个脑袋在这些研究中，我们将阐明具有特殊抑制活性的抗病毒抗体是如何发挥其作用的， 细胞培养和体内。该方法将包括高效分离人mAb， 基于下一代测序的创新抗体基因库研究。几个假设将被测试， 包括由两种抗体的特征（选择）产生的超强中和活性的概念 最佳V-D-J克隆型和关键体细胞突变的积累）和抗原（结合 多个相邻包膜蛋白上的四级表位和对病毒关键的结构转换的阻断 进入或释放）。我们还将应用新技术，通过受体介导的分子转移， 使用Fc区中的工程化序列改变来改善血脑屏障。虽然我们的重点是了解 如何以及为什么超有效的人类单克隆抗体抑制EEEV，研究可能会相关的一般原则， 抗体中和许多不同的脑炎病毒。除了定义分子和结构 基于抗体中和EEEV和部署新的策略，将生物制剂输送到大脑，这些 研究将产生一组完全人源的单克隆抗体，可以预防和治疗EEEV感染，这可能是 在不久的将来，它可能成为人类的治疗药物。该项目的研究虽然针对 EEEV，可能会告知未来的抗体和/或疫苗的努力，对其他虫媒病毒，造成人类大脑 感染.我们已经召集了一个独特的调查小组，包括一个人类抗体专家，一个分子生物学专家， 具有Ab-病毒相互作用经验的病毒学家，具有特异性抗体的动物模型和发病机制专家， 在脑炎甲病毒，包括EEEV，和脑靶向科学家的专业知识，以追求这些研究。

SUMMARY: Eastern equine encephalitis virus (EEEV) is a re-emerging mosquito-borne alphavirus that causes a debilitating encephalitic illness in humans. About a third of human cases of EEEV infection die and many survivors have long-term, debilitating neurologic problems. The virus is maintained in an enzootic cycle between Culiseta melanura mosquitoes and avian hosts but can be transmitted to humans and horses by some Aedes, Coquillettidia, and Culex species. The infection is unusual in humans but increasing in frequency in recent years, likely secondary to climate changes, vector expansion, and other uncharacterized factors. EEEV also is regarded as a potential bioterrorism threat due to spread via aerosol route. Despite the highly pathogenic nature of the virus, no specific treatment or vaccine for EEEV is available. A primary goal of this project is to define the molecular, genetic, immunologic, and structural characteristics of ultra-potent neutralizing human mAbs with broad activity in vivo against EEEV. Additional goals include defining the mechanistic correlates of protection by these ultra-potent neutralizing mAbs and determining ways to optimize function and deliver to the brain. In these studies, we will elucidate how antiviral Abs with exceptional inhibitory activity exert their action in cell culture and in vivo. The approach will include high efficiency isolation of human mAbs, coupled with innovative antibody gene repertoire studies based on next-gen sequencing. Several hypotheses will be tested, including the concept that ultra-potent neutralizing activity results from features of both the antibodies (selection of optimal V-D-J clonotypes and accumulation of critical somatic mutations) and the antigen (binding to quaternary epitopes on multiple adjacent envelope proteins and blockade of structural transitions critical for virus entry or release). We also will apply new technologies for receptor-mediated transfer of molecules across the blood-brain barrier using engineered sequence changes in the Fc region. Although our focus is to understand how and why ultra-potent human mAbs inhibit EEEV, the studies likely will be relevant to general principles of antibody neutralization of many different encephalitic viruses. In addition to defining the molecular and structural basis of Ab neutralization of EEEV and deploying new strategies for delivery of biologics to the brain, these studies will generate a group of fully human mAbs that can prevent and treat EEEV infection, which could be developed in the near future as a possible therapeutic for humans. Studies in this project, while targeted against EEEV, likely will inform future Ab-based and/or vaccine efforts against other arboviruses that cause human brain infections. We have assembled a unique group of investigators, including a human Ab expert, a molecular virologist with experience in Ab-virus interactions, an animal model and pathogenesis expert with specific expertise in encephalitic alphaviruses, including EEEV, and brain-targeting scientists to pursue these studies.