Mechanisms of Neutralizing Antibody Resistance in Chronic HCV and HIV Infection

描述（由申请人提供）：该K 08职业发展奖的研究目标是确定介导逃避自体中和抗体（nAb）的丙型肝炎病毒（HCV）包膜突变的共享模式，测量这些突变的适应性成本，并确定编码HCV感染期间诱导的广泛中和抗体的人B细胞库。通过指导，结构化教学和实验室经验，这个K 08职业发展奖是一个理想的机制，让贾斯汀·贝利博士成为一个独立的研究者进行广泛的HCV感染中和抗体反应的转化研究。候选人：贝利医生是约翰霍普金斯医院传染病研究员培训的最后一年的医生。他获得了医学博士学位。和博士2007年，她通过医学科学家培训计划在约翰霍普金斯大学医学院获得免疫学硕士学位，并于2009年通过ABIM研究途径在马萨诸塞州总医院完成内科住院医师培训。他花了几年的研究，他的传染病奖学金研究丙型肝炎病毒（HCV）包膜的演变与他的主要导师，博士。他的短期目标是识别和表征HCV nAb逃逸突变，定义广泛nAb应答的遗传特征，获得杂交瘤生成和深度测序的实践经验，并在生物信息学方法和B细胞免疫学方面进行教学培训。他的长期目标是成为一名独立的研究者，研究病毒进化和B细胞库的进化导致广泛的nAb应答的机制。工作环境：本提案中描述的研究将在约翰霍普金斯医院传染病科教授Stuart Ray博士和国际公认的HCV病毒学、体液免疫和计算生物学专家James E.小克罗，他是范德比尔特大学医学中心的儿科、微生物学和免疫学教授，也是B细胞生物学和开发有效B细胞对人体病毒反应的分子基础方面的专家。两位导师都是各自领域的领导者，资金充足，在指导年轻调查人员独立方面有着良好的记录。两位导师的实验室都有必要的设备，以完成拟议的研究，相关的患者样本，抗体和其他试剂都很容易获得。调研：丙型肝炎病毒（HCV）的疫苗是迫切需要的，诱导有效的中和抗体反应可能是任何成功的疫苗策略的基石。困难在于HCV复制到高水平 使用易错聚合酶，导致病毒在世界范围内广泛的遗传多样性和感染个体中的快速病毒进化。大多数抗体在自然感染过程中诱导产生 不具有足够广泛的特异性来中和不同的HCV分离株，并且病毒进化可导致感染个体逃避nAb应答。然而，罕见的感染个体会产生广泛的nAb应答，并且某些表位中的nAb逃逸突变可能会给病毒带来显著的适应性成本。本研究的目的是确定丙型肝炎病毒（HCV）包膜突变的共同模式，介导逃避自体中和抗体（nAb），以衡量这些突变的健身成本，并确定人类B细胞库编码广泛的中和抗体在HCV感染期间诱导。更好地理解这些问题将有助于HCV疫苗的开发，通过确定免疫原性，但健身受限的表位，可能作为疫苗抗原，也通过定义广泛的nAb的遗传特征，应诱导针对HCV的疫苗。本建议书中描述的研究是新颖的，可在奖励期内实现，并具有很高的潜在意义。通过完成这项工作获得的研究经验，密集的指导和结构化的教学，这个K 08职业发展奖将允许主要研究者Justin Bailey博士成为一名独立的研究者，对HCV感染中的广泛中和抗体反应进行转化研究。据世界卫生组织估计，全球有1.7亿人感染丙型肝炎病毒（HCV），在大多数国家，HCV感染占总人口的1-2%。迫切需要一种预防或减弱HCV感染的疫苗，刺激有效的中和抗体（nAb）应答可能是任何成功疫苗策略的关键。因此，更好地了解病毒从nAb逃逸和广泛的nAb应答的发展应有助于HCV疫苗的开发。

DESCRIPTION (provided by applicant): The research objectives of this K08 career development award are to to define shared patterns of hepatitis C virus (HCV) envelope mutation that mediate escape from autologous neutralizing antibody (nAb), to measure the fitness costs of those mutations, and to define the human B cell repertoire encoding broadly neutralizing antibodies induced during HCV infection. Through mentoring, structured didactics and laboratory experience, this K08 career development award is the ideal mechanism to allow Dr. Justin Bailey to become an independent investigator conducting translational research on broadly neutralizing antibody responses in HCV infection. Candidate: Dr. Bailey is a physician in his final year of fellowship training in Infectious Diseases at the Johns Hopkins Hospital. He earned an M.D. and Ph.D. in Immunology at the Johns Hopkins University School of Medicine through the Medical Scientist Training Program in 2007 and completed residency training in Internal Medicine at the Massachusetts General Hospital through the ABIM research pathway in 2009. He has spent the research years of his Infectious Diseases fellowship studying hepatitis C virus (HCV) envelope evolution with his primary mentor, Dr. Stuart Ray. His short term goals are to identify and characterize HCV nAb escape mutations, to define genetic characteristics of a broad nAb response, to gain practical experience in hybridoma generation and deep sequencing, and to pursue didactic training in bioinformatic methods and B cell immunology. His long term goal is to become an independent investigator studying the mechanisms by which viral evolution and evolution of the B cell repertoire can lead to a broad nAb response. Environment: The investigations described in this proposal will be performed in the laboratories of Dr Stuart Ray, a Professor in the Infectious Diseases Division at Johns Hopkins Hospital and an internationally- recognized expert in HCV virology, humoral immunity, and computational biology and Dr. James E. Crowe, Jr., a Professor of Pediatrics, Microbiology and Immunology at Vanderbilt University Medical Center and an expert in B cell biology and the molecular basis for the development of effective B cell responses to viruses in humans. Both mentors are leaders in their respective fields, are well-funded, and have a strong track record of mentoring young investigators to independence. Necessary equipment is available in the labs of both mentors for the completion of the proposed studies, and relevant patient samples, antibodies, and other reagents are readily available. Research: A vaccine against hepatitis C virus (HCV) is urgently needed, and induction of an effective neutralizing antibody response will likely be a keystone of any successful vaccine strategy. The difficulty lies in the fact that HCV replicates to high levels using an error-prone polymerase, leading to extensive world-wide genetic diversity of the virus and rapid viral evolution in infected individuals. Most antibodies induced during natural infection do not have broad enough specificity to neutralize diverse HCV isolates, and viral evolution can lead to escape from nAb responses in individuals who become infected. However, rare infected individuals develop broad nAb responses, and nAb escape mutations in some epitopes may convey significant fitness cost to the virus. The goal of this investigation is to define shared patterns of hepatitis C virus (HCV) envelope mutation that mediate escape from autologous neutralizing antibody (nAb), to measure the fitness costs of those mutations, and to define the human B cell repertoire encoding broadly neutralizing antibodies induced during HCV infection. A better understanding of these questions will facilitate HCV vaccine development by identifying immunogenic but fitness-constrained epitopes that might serve as vaccine antigens and also by defining genetic features of broadly nAb that should be induced by a vaccine against HCV. The research described in this proposal is novel, achievable within the award period, and of high potential significance. Through the research experience acquired through completion of this work, intensive mentoring, and structured didactics, this K08 career development award will allow the primary investigator, Dr. Justin Bailey, to become an independent investigator conducting translational research on broadly neutralizing antibody responses in HCV infection. Relevance The World Health Organization estimates there are 170 million persons with hepatitis C virus (HCV) infection worldwide, and in most countries, HCV infection is found in 1-2% of the general population. A vaccine to prevent or attenuate HCV infection is urgently needed, and stimulation of effective neutralizing antibody (nAb) responses will likely be a keystone of any successful vaccine strategy. Therefore, a better understanding of viral escape from nAb and development of broadly nAb responses should facilitate HCV vaccine development.