Env evolution in humans and RMs

人类和 RM 的环境进化

• 批准号: 10117175
• 负责人: GEORGE M SHAW
• 金额: $ 109.37万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-03-07 至 2022-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10117175
• 关键词: Amino Acid Substitution; Animal Model; Animals; Antibodies; Antibody Response; Antibody Specificity; Antigens; Autologous; B-Cell Antigen Receptor; B-Lymphocytes; Binding; Bioinformatics; Biological Models; CD4 Positive T Lymphocytes; Cell Culture Techniques; Clinical; DNA; Data; Data Analyses; Development; Epitopes; Evolution; Fingerprint; Genetic; HIV; HIV Envelope Protein gp120; HIV-1; HIV-1 vaccine; Human; Immune system; Immunity; Immunize; In Vitro; Infection; Kinetics; Lead; Link; Macaca mulatta; Maps; Molecular; Molecular Conformation; Pathway interactions; Pattern; Peptides; Polysaccharides; Primary Infection; Reproducibility; Rhesus; Sampling; Site-Directed Mutagenesis; Specificity; Testing; Time; Ursidae Family; Vaccinated; Vaccine Design; Vaccines; Variant; Virus; Virus Diseases; design; env Gene Products; expression cloning; in vivo; monomer; neutralizing antibody; novel; pre-clinical; response; simian human immunodeficiency virus; transmission process; vaccine candidate; vaccine development; vaccine trial; vector; virtual

SUMMARY Excluding the great apes, the immune system of Indian rhesus macaques (RMs) most closely approximates that of humans. Thus, it is widely believed that the RM represents the closest practical animal model for evaluating protective immunity to HIV-1 and vaccines that might elicit such protection. For the analysis of HIV-1 neutralizing antibodies (NAbs), RMs have in the past been infected with simian-human immunodeficiency viruses (SHIVs) that bear HIV-1 Envs that were heavily adapted in cell culture or by animal passage, or they were immunized with any of numerous Env containing candidate vaccines ranging from Env peptides or DNA vectors to gp120 monomers to soluble stabilized Env trimers (SOSIPs). The findings from all such studies to date have been the same: Abs can be generated that neutralize heterologous tier 1 viruses, and in some instances autologous tier 2 viruses, but generally not heterologous tier 2 viruses that constitute virtually all primary HIV-1 strains and are responsible for clinical HIV-1 transmission. Surprisingly, there is no direct experimental evidence that RMs have the potential to develop heterologous tier 2 broadly neutralizing antibodies (bNAbs) even if vaccinated with an appropriate immunogen. Thus, a major roadblock to HIV-1 vaccine development is that there is no animal model system where the elicitation of HIV-1 bNAbs can be reliably and consistently demonstrated, let alone be studied in an iterative fashion for rational vaccine design. Project 1 seeks to overcome this roadblock by capitalizing on recent discoveries by the Shaw lab regarding novel SHIV design strategies. The scientific premise of Project 1 is that since most examples of bNAb elicitation come from natural human infection by primary strains of HIV-1, the most likely means to elicit bNAbs in RMs is by infection with SHIVs bearing primary HIV-1 Envs in their native conformations. A key hypothesis that we will test is that SHIVs bearing primary or transmitted/founder (T/F) Envs will engage rhesus germline and intermediate ancestor B cell receptors (BCRs) that are orthologous to those engaged by the same Envs in human infection and that patterns of virus-Ab coevolution leading to the development of neutralizing antibody specificity, potency and breadth will be similar in both species. Specific Aims of Project 1 are to: (i) analyze in 33 RMs the in vivo replication kinetics and NAb responses of 11 novel SHIVs whose Envs are known to bind to human bNAb lineage BCRs targeting the V3-glycan supersite (CH848, CH694, CH040), V1V2 supersite (CAP256SU, ZM233, WITO, Q23, T250-4, CH1012), CD4bs (CH505) or other (BG505), and down-select to two SHIVs for inoculation into 9 RMs each; (ii) analyze in vivo replication kinetics and env evolutionary pathways of SHIVs targeting V3-glycan or V1V2 germline and IA BCRs; and (iii) determine the kinetics, potency and breadth of polyclonal NAb responses and map epitope specificities by a combination of Env fingerprinting, Env-expression cloning, and site-directed mutagenesis. Project 1 will link closely with Cores B and C for sequencing and bioinformatics and Projects 2 and 3 for sample provision and data interpretation.

概括 除类人猿外，印度恒河猴 (RM) 的免疫系统最接近 人类的。因此，人们普遍认为 RM 代表了最接近的实用动物模型。 评估对 HIV-1 的保护性免疫力和可能引起这种保护的疫苗。用于 HIV-1 分析 中和抗体（NAb），RM过去曾感染过猿人免疫缺陷病 携带 HIV-1 包膜的病毒 (SHIV) 在细胞培养或动物传代中得到了高度适应，或者它们 使用多种含有 Env 候选疫苗（包括 Env 肽或 DNA）中的任何一种进行免疫 载体到 gp120 单体到可溶性稳定的 Env 三聚体 (SOSIP)。所有此类研究的结果 日期相同：可以产生中和异源 1 级病毒的抗体，并且在某些情况下 实例是自体 2 级病毒，但通常不是构成几乎所有病毒的异源 2 级病毒。 主要 HIV-1 毒株并负责临床 HIV-1 传播。令人惊讶的是，没有直接的 实验证据表明 RM 有潜力开发异源 2 层广泛中和 即使接种了适当的免疫原，也会产生抗体（bNAb）。因此，HIV-1 的主要障碍 疫苗开发的一个缺点是没有动物模型系统可以诱导 HIV-1 bNAb 可靠且一致地得到证明，更不用说以迭代方式研究合理的疫苗设计了。 项目 1 试图通过利用 Shaw 实验室关于以下方面的最新发现来克服这一障碍： 新颖的 SHIV 设计策略。项目 1 的科学前提是，由于大多数 bNAb 实例 诱导来自人类自然感染 HIV-1 的原代毒株，这是诱导 bNAb 的最有可能的方法 RM 中的感染是通过感染具有原始构象的原始 HIV-1 包膜的 SHIV 来实现的。一个关键假设 我们要测试的是，携带原代或传播/创始人 (T/F) 环境的 SHIV 会与恒河猴种系结合 和中间祖先 B 细胞受体 (BCR)，它们与参与相同 Env 的受体是直系同源的 人类感染以及病毒-抗体共同进化模式导致中和抗体的产生 两个物种的特异性、效力和广度相似。项目 1 的具体目标是： (i) 分析 33 RMs 11 种新型 SHIV 的体内复制动力学和 NAb 反应，已知其 Env 与其结合 靶向 V3-聚糖超级位点（CH848、CH694、CH040）、V1V2 超级位点的人 bNAb 谱系 BCR (CAP256SU、ZM233、WITO、Q23、T250-4、CH1012)、CD4bs (CH505) 或其他 (BG505)，然后向下选择 两份 SHIV，分别接种到 9 个 RM 中； (ii) 分析体内复制动力学和环境进化 SHIV 靶向 V3 聚糖或 V1V2 种系和 IA BCR 的途径； (iii) 确定动力学， 多克隆 NAb 反应的效力和广度以及 Env 组合的图谱表位特异性 指纹识别、Env 表达克隆和定点突变。项目1将与Cores B紧密联系 和 C 用于测序和生物信息学，项目 2 和 3 用于样本提供和数据解释。