MPER broadly neutralizing antibody knockin mice to study anti-HIV Bcell responses

MPER 广泛中和抗体敲入小鼠用于研究抗 HIV B 细胞反应

• 批准号: 7841551
• 负责人: Laurent Karl Verkoczy
• 金额: $ 38.3万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-04-01 至 2015-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7841551
• 关键词: Acquired Immunodeficiency Syndrome; Affinity; Anti-Retroviral Agents; Antibodies; Antibody Formation; Antigens; Autoantigens; B cell repertoire; B-Cell Development; B-Lymphocytes; Back; Binding; Bone Marrow; Charge; DNA Sequence Rearrangement; Defect; Developing Countries; Development; Engineering; Epitopes; Exhibits; Gene Targeting; Goals; HIV Envelope Protein gp120; HIV-1; HIV-1 vaccine; Human; Immune response; Immunization; Immunoglobulin Variable Region; Immunoglobulins; In Vitro; Individual; Infection; Knock-in Mouse; Light; Modeling; Modification; Monoclonal Antibodies; Mouse Strains; Mus; Mutate; Mutation; Patients; Peripheral; Pharmaceutical Preparations; Polysaccharides; Population; Process; Production; Regulation; Relative (related person); Role; Self Tolerance; Series; Shapes; Structural Genes; Structure; Testing; Vaccination; Vaccines; anergy; arm; autoreactivity; base; central tolerance; design; genetic immunization strategies; in vivo; neutralizing antibody; novel; novel strategies; pandemic disease; prevent; prophylactic; public health relevance; receptor; research study; response; simian human immunodeficiency virus

DESCRIPTION (provided by applicant): The identification of a few rarely made antibodies to different HIV-1 envelope epitopes which are capable of neutralizing a broad range of HIV-1 isolates in vitro and controlling SHIV infection in vivo has provided hope for achieving an antibody-based HIV-1 vaccine strategy. One of these rare antibodies, 2F5, has particularly potent and broad neutralizing activity and is directed against an attractive antibody-based vaccine target, the MPER epitope of the HIV-1 gp41 region. 2F5 has unusually long charged CDR3s and exhibits polyreactivity, raising the possibility that antibodies like 2F5 cannot be elicited because the B cells from which they originate have reactivity with host antigens. Using a gene-targeting approach, we have generated mice (2F5 VH) with directed expression of the original 2F5 heavy chain (HC) variable region into the mouse HC locus, and made the important observation that 2F5 HC-expressing B cells are primarily deleted in the bone marrow at the pre-B to immature transition. Despite this profound defect, a small, but detactable population of B cells are present in the periphery which retain the 2F5 HC. In this application, we propose to comprehensively extend our characterization of 2F5 VH mice, first to test the hypothesis that most of their remaining peripheral B cells have lost autoreactivity, either by LC editing, anergy or modification of the 2F5 HC. Using a systematic array of genetic, immunization, and pharmacological approaches to modulate self-tolerance, we will then test the hypothesis that these mice can be pushed into producing high titers of broadly neutralizing antibodies. Finally, we will extend/refine our studies in 2F5 VH mice by using a series of "back-mutated" 2F5 VH mice (expressing 2F5 VH regions that are either germline or have different selected back-mutations), to examine the ability of the 2F5 precursor B cell repertoire, when shaped by immunization-driven affinity maturation, to generate "2F5-like" neutralizing antibodies. PUBLIC HEALTH RELEVANCE: The development of a protective antibody-based HIV-1 vaccine remains an enormous challenge. In this study, we propose to use a series of mouse strains we have engineered to express different versions of the broadly and potently neutralizing HIV-1 antibody 2F5 in order to: 1) determine how the processes of self-tolerance and affinity maturation impact the ability of B cells to make neutralizing antibodies, and 2) to examine if appropriate manipulation of these processes can elicit B cells to make such antibodies. These experiments should be helpful in formulating novel strategies for properly eliciting protective HIV-1 antibodies in patients.

描述（由申请人提供）：鉴定了几种对不同HIV-1包膜表位的抗体很少制成的抗体，这些抗体能够中和，可以中和广泛的HIV-1分离株体外，并在体内控制SHIV感染为实现基于HIV的HIVBODOY HIVIBODY HIM-1疫苗疫苗策略提供了希望。这些稀有抗体之一2f5具有特别有效且广泛的中和活性，并且针对有吸引力的基于抗体的疫苗靶标，即HIV-1 GP41区域的MPER表位。 2F5具有异常长的电荷CDR3，并且表现出多反应性，从而提高了无法引起2F5之类的抗体的可能性，因为它们起源的B细胞与宿主抗原具有反应性。 使用基因靶向方法，我们产生了小鼠（2F5 VH），其定向表达原始2f5重链（HC）可变区域中的小鼠进入了小鼠HC基因座，并使得对2f5 HC表达B细胞的重要观察主要是在骨髓中主要删除了Pre-b to bone-b to pre-b to Pre-b to bone-b to bone-brow to bone-b to pre b bone botity to bone-brow。尽管存在这种严重的缺陷，但在保留2f5 HC的外围存在一个小但可被耐受的B细胞群体。 在此应用中，我们建议全面扩展我们对2F5 VH小鼠的表征，首先测试假说，即它们剩余的大多数外围B细胞都通过LC编辑，消极或2F5 HC的修改而失去了自动反应性。然后，我们将使用一系列遗传，免疫和药理学方法来调节自我耐受，然后测试以下假设：这些小鼠可以将这些小鼠推入产生广泛中和抗体的高滴度。最后，我们将通过使用一系列“反射” 2F5 VH小鼠（表达2F5 VH区域或具有不同选择的背部突变的2F5 VH区域），扩展/完善我们在2F5 VH小鼠中的研究，以检查2F5前体B细胞曲目的能力，当通过免疫化型亲和型族型中的生成型'2f5-foseptib to to to for to for to fosefib'2f5。 公共卫生相关性：基于保护抗体的HIV-1疫苗的开发仍然是一个巨大的挑战。在这项研究中，我们建议使用一系列的小鼠菌株，以表达广泛而有效的中和中和的HIV-1抗体2F5的不同版本，以：1）确定自我耐受性和亲和力的过程如何影响B细胞的能力如何使中和抗体进行中和抗体的能力进行中和抗体，以及将这些过程进行适当的挑战，以使B型均能进行by andib的操作。这些实验应有助于制定新的策略，以适当引起患者的保护性HIV-1抗体。