Protective B-cell responses in chikungunya virus infection

基孔肯雅病毒感染中的保护性 B 细胞反应

• 批准号: 9117149
• 负责人: GRAHAM SIMMONS
• 金额: $ 43.64万
• 依托单位: VITALANT
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-19 至 2016-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9117149
• 关键词: Acute; Address; Alphavirus; Alphavirus Infections; Animal Model; Antibodies; Antibody Binding Sites; Antigens; Arboviruses; Area; Arthralgia; Arthritis; B cell repertoire; B-Lymphocyte Epitopes; B-Lymphocytes; Bar Codes; Binding; Biological Assay; Caribbean region; Cell Separation; Cells; Central America; Chikungunya virus; Chronic; Common Epitope; Data Set; Development; Disease; Disease Outbreaks; Economics; Enrollment; Enzyme-Linked Immunosorbent Assay; Epidemic; Epitopes; Escape Mutant; Event; Evolution; Fever; Genbank; Generations; Genes; Genetic Variation; Glycoproteins; Goals; Health; Human; Immune; In Vitro; Individual; Infection; Lead; Licensing; Light; Luciferases; Maps; Mediating; Membrane; Memory B-Lymphocyte; Monoclonal Antibodies; Mutagenesis; Mutation; Nature; Patients; Phenotype; Plasmablast; Population; Production; Public Health; Recovery; Reporter; Serum; South America; Staging; Structure; Surface; Technology; Therapeutic; United States; Vaccines; Variant; Viral; Viral Antigens; Virion; Virus; Virus Diseases; West Nile virus; deep sequencing; genetic evolution; human monoclonal antibodies; in vivo; neutralizing antibody; novel; particle; pressure; prevent; prophylactic; response; screening; surveillance study; transmission process; vaccine development; vector mosquito; virus envelope; virus genetics

 DESCRIPTION (provided by applicant): Chikungunya virus (CHIKV) has the potential to create a major public health impact should it be introduced into the United States, as seems likely following a large and sustained outbreak in the Caribbean. CHIKV causes extensive human and economic damage, primarily due to acute fever and arthralgia and post-viral chronic joint pain/arthritis. Currently no licensed therapeutic treatments or vaccines exist for CHIKV. We will address the important public health threat posed by CHIKV by identifying lead candidate monoclonal antibodies (mAbs) for development into treatments capable of being used both prophylactically and therapeutically. Importantly, we have demonstrated the ability of mAbs directed against CHIKV to block viral assembly/budding - probably by preventing the envelope glycoprotein-driven membrane curvature required to form particles. We will characterize new antibodies targeting this mechanism, as well as describe the full B-cell repertoire in response to infection - both in acutely infected patients and recovered individuals. Finally, we will characterize CHIKV genetic diversity and evolution with emphasis on detecting variation and signatures of selection at B-cell epitopes. In order to achieve these goals we will perform three Specific Aims: Aim 1. Identification and characterization of potent human monoclonals capable of budding inhibition. We will derive and screen B-cell clones from recovered CHIKV patients specifically for inhibition of CHIKV virus release/budding. Resulting mAbs will be characterized for in vitro and in vivo potency, and their epitopes will be mapped using escape mutants and mutagenesis. Aim 2. Characterize acute and memory B-cell responses to CHIKV infection. Using immune repertoire capture (IRC) technology, we will fully map B-cell repertoires during CHIKV infection. Common epitopes will be identified by looking for convergent evolution of B-cell paratopes in multiple individuals, and the relationship between entry neutralization and budding inhibition will be characterized in acutely infected and recovered individuals. Aim 3. Characterization of CHIKV envelope glycoprotein diversity and evolution. In order to assess the potential for the antibodies derived in Aims 1 and 2 to be broadly cross reactive, we will characterize the nature and extent of CHIKV envelope sequence variation in viral isolates derived from individuals enrolled in the study (over three years) together with CHIKV sequences from the wider global population. Data sets will be screened for signatures of selective pressure, particularly from the humoral response. In summary, we hope to develop novel mAbs, targeting specific stages of the viral lifecycle. The humoral responses during infection will be mapped and related to viral diversity and evolution.

 描述（由申请人提供）：基孔肯雅病毒（CHIKV）如果被引入美国，就有可能对公共卫生产生重大影响，在加勒比海地区大规模持续爆发后，这种情况似乎很可能发生。 CHIKV 造成广泛的人类和经济损失，主要是由于急性发烧和关节痛以及病毒后慢性关节痛/关节炎。目前尚无针对 CHIKV 的许可治疗方法或疫苗。我们将通过确定主要候选单克隆抗体 (mAb) 来开发可用于预防和治疗的治疗方法，从而应对 CHIKV 带来的重要公共卫生威胁。重要的是，我们已经证明了针对 CHIKV 的单克隆抗体能够阻止病毒组装/出芽——可能是通过阻止形成颗粒所需的包膜糖蛋白驱动的膜曲率。我们将描述针对这一机制的新抗体的特征，并描述针对感染的完整 B 细胞库 - 无论是在急性感染患者还是康复个体中。最后，我们将描述 CHIKV 遗传多样性和进化的特征，重点是检测 B 细胞表位的变异和选择特征。为了实现这些目标，我们将实现三个具体目标： 目标 1. 鉴定和表征能够抑制出芽的有效人类单克隆抗体。我们将从康复的 CHIKV 患者中衍生和筛选 B 细胞克隆，专门用于抑制 CHIKV 病毒释放/出芽。所得单克隆抗体将进行体外和体内效力表征，并且将使用逃逸突变体和诱变来绘制它们的表位。目标 2. 表征 B 细胞对 CHIKV 感染的急性和记忆反应。利用免疫组库捕获 (IRC) 技术，我们将完整绘制 CHIKV 感染期间 B 细胞组库的图谱。通过寻找多个个体中 B 细胞互补位的趋同进化，将鉴定常见表位，并且将在急性感染和康复个体中表征进入中和和出芽抑制之间的关系。目标 3. CHIKV 包膜糖蛋白多样性和进化的表征。为了评估目标 1 和目标 2 中产生的抗体广泛交叉反应的潜力，我们将描述来自参与研究的个体（超过三年）的病毒分离株中 CHIKV 包膜序列变异的性质和程度，以及来自更广泛的全球人群的 CHIKV 序列。将筛选数据集以寻找选择性压力的特征，特别是来自体液反应的特征。 总之，我们希望开发针对病毒生命周期特定阶段的新型单克隆抗体。感染期间的体液反应将被绘制出来并与病毒多样性和进化相关。