Mapping the germinal center and memory B cell landscape to complex antigens

将生发中心和记忆 B 细胞景观映射到复杂抗原

• 批准号: 10473006
• 负责人: Robert Koehler Abbott
• 金额: $ 25.1万
• 依托单位: UNIVERSITY OF TEXAS MED BR GALVESTON
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-20 至 2023-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10473006
• 关键词: Affect; Affinity; Antibodies; Antibody Response; Antigens; Apoptosis; Avidity; B cell repertoire; B-Lymphocyte Subsets; B-Lymphocytes; Back; Binding; Biological Models; Biological Process; Biology; Bone Marrow; Cell Compartmentation; Cell physiology; Cells; Cellular biology; Clinical Trials; Clone Cells; Complex; Data; Development; Engineering; Epitopes; Exhibits; Experimental Models; Failure; Frequencies; Genes; HIV; HIV Seronegativity; HIV envelope protein; HIV vaccine; Helper-Inducer T-Lymphocyte; Human; Hypoxia; Immune response; Immunity; Immunization; Immunoglobulin Somatic Hypermutation; Immunologics; Individual; Infection; Institutes; Knowledge; Laboratories; Link; Mediating; Memory; Memory B-Lymphocyte; Mentors; Metabolic; Metabolic Pathway; Methods; Modality; Modeling; Mus; Mutate; Output; Pathway interactions; Pharmacology; Phase; Phenotype; Physiological; Plasma Cells; Play; Population; Process; Production; Property; Recording of previous events; Research; Role; Scientist; Series; Signal Pathway; Structure of germinal center of lymph node; System; T-Lymphocyte; Testing; Time; Training; Transgenic Organisms; Vaccination; Vaccine Antigen; Vaccine Design; Vaccines; Visit; Work; base; design; experience; mouse model; neutralizing antibody; novel; pandemic disease; pathogen; plasma cell development; precursor cell; public health intervention; recruit; response; success; vaccine candidate; vaccine trial

ABSTRACT Vaccines are one of the most successful public health interventions over the past century. Of the 28 licensed vaccines, nearly all of them work by induction of protective antibodies capable of neutralizing the pathogen. However, our understanding of the cellular dynamics of immune responses to vaccines, particularly the biology surrounding B cell competition within germinal centers (GC) and memory B cell biology to complex vaccine antigens, has remained limited. This lack of fundamental understanding of these biological processes may be a contributor to the failure to develop an effective HIV vaccine, despite nearly 30 years of research. The fact that a small population of HIV+ individuals develop broadly neutralizing antibodies (bnAbs) gives renewed hope that an HIV vaccine is indeed possible. Recent work has found that many HIV negative healthy human donors have VRC01-class precursor B cells. However, work from these studies revealed that these potential bnAb precursor B cells are found at an unusually rare frequency, suggesting that following immunization these B cells would be outcompeted by more frequent non-neutralizing B cells. To answer immunological questions surrounding this problem, I developed a model system utilizing mice containing human genes for the germline- reverted VRC01 bnAb (VRC01gHL), together with teams from the labs of Dr. David Nemazee and Dr. William Schief. Through this B cell transfer model, we found that antigen affinity, avidity, and precursor frequency all played interdependent roles in competitive success of rare VRC01gHL B cells in GCs. Critically, we found that rare VRC01gHL B cells with physiological affinities could be primed to successfully compete within GCs and form memory. In this K99/R00 proposal I will build on these findings. I will explore how precursor frequency and affinity affect the balanced output of memory B cell and long lived plasma cells from GCs, and how Tfh help can modulate these processes. I will assess how these parameters affect recall and competitive success of VRC01gHL memory B cells. Moreover, I will investigate if different metabolic pathways are involved in successful recruitment of memory VRC01gHL B cells to and within secondary GCs. I will further my training by developing a co-T cell transfer method to specifically study the impact of different Tfh pathways in competitive success of VRC01gHL B cells. The K99 phase will be conducted in the laboratory of Dr. Shane Crotty at the La Jolla Institute (LJI). Dr. Crotty is an ideal mentor as he has a highly successful history in studying vaccine biology, particularly T follicular helper (Tfh) biology. He has also explored this biology related to HIV vaccines. I will additionally receive formal training in antibody characterization through coursework and further develop real world training in immunogen production and design in the laboratory of Dr. William Schief as a visiting scientist. During the R00 phase, I will take my experimental models with me and investigate multiple parameters affecting memory cell biology. These will include studying the roles of circulating antibody, memory Tfh, and “metabolic memory” of B cells.

抽象的 疫苗是过去一个世纪最成功的公共卫生干预措施之一。 28个许可 疫苗，几乎所有的疫苗都通过诱导能够中和病原体的保护性抗体起作用。 但是，我们对疫苗免疫呼吸的细胞动力学的理解，尤其是生物学 周围生发中心（GC）内的B细胞竞争和记忆B细胞生物学到复杂疫苗 抗原，仍然有限。缺乏对这些生物过程的基本了解可能是 导致未能开发有效的艾滋病毒疫苗，迫切需要研究近30年的研究。事实 少数艾滋病毒+个体群体形成广泛中和抗体（BNAB）给人带来的新希望，希望 艾滋病毒疫苗确实是可能的。最近的工作发现，许多艾滋病毒负面健康的人类捐助者有 VRC01级前体B细胞。但是，这些研究的工作表明这些潜在的BNAB 前体B细胞以异常罕见的频率发现，这表明在免疫后这些B 细胞将被更常见的非中和B细胞所吸引。回答免疫学问题 围绕这个问题，我使用含有人类基因的生殖线的小鼠开发了一个模型系统。 David Nemazee博士和William博士的团队以及William博士的团队以及William博士 Schief。通过此B细胞转移模型，我们发现抗原亲和力，亲和力和前体频率al 在GC中稀有VRC01GHL B细胞的竞争成功中起着相互依存的作用。至关重要的是，我们发现 具有物理亲和力的罕见VRC01GHL B细胞可以在GCS中成功竞争，并且 形式记忆。在此K99/R00建议中，我将以这些发现为基础。我将探索前体频率 和亲和力会影响记忆B细胞的平衡输出和GC的长期浆细胞以及TFH的如何 帮助可以调节这些过程。我将评估这些参数如何影响回忆和竞争成功 VRC01GHL内存B细胞的元素。此外，我将调查是否参与了不同的代谢途径 成功地募集了记忆VRC01GHL B细胞到次级GC内和内部。我将通过 开发一种Co-T细胞转移方法，以专门研究不同TFH途径在竞争激烈的影响 VRC01GHL B细胞的成功。 K99阶段将在LA的Shane Crotty博士实验室进行 Jolla Institute（LJI）。 Crotty博士是一个理想的心理，因为他在研究疫苗方面拥有非常成功的历史 生物学，尤其是T卵泡辅助器（TFH）生物学。他还探索了与HIV疫苗有关的这种生物学。我 还将通过课程进行抗体表征的正式培训，并进一步发展 威廉·西弗（William Schief）博士实验室的免疫原生产和设计培训作为访问 科学家。在R00阶段，我将与我一起进行实验模型并研究多个 影响记忆细胞生物学的参数。这些将包括研究循环抗体的作用，记忆 TFH和B细胞的“代谢记忆”。