Proteolytic Antibody HIVcides

蛋白水解抗体杀艾滋病剂

基本信息

批准号：
7286844
负责人：
Sudhir Paul
金额：
$ 20.66万
依托单位：
UNIVERSITY OF TEXAS HLTH SCI CTR HOUSTON
依托单位国家：
美国
项目类别：
财政年份：
2006
资助国家：
美国
起止时间：
2006-09-15 至 2009-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7286844
关键词：
Antibodies Antibody-Producing Cells Architecture B-Lymphocytes Binding CD4 Positive T Lymphocytes Catalytic Antibodies Cell Fractionation Cell Line Class Coitus Condition Development Drug Formulations Environment Excipients HIV HIV Envelope Protein gp120 HIV Seropositivity Immune Immunization Immunoglobulin A Immunoglobulin G In Vitro Infection Local Microbicides Lupus Lymphocyte Macaca Modeling Molecular Patients Phase Property Prophylactic treatment Rate Reaction Risk Salivary Serum Sexual Transmission Simulate Site Specificity Superantigens Vagina Variant analog base catalyst cost desire env Gene Products improved in vivo microbicide novel pandemic disease peptide analog polyclonal antibody resistance factors

Antibodies Antibody-Producing Cells Architecture B-Lymphocytes Binding CD4 Positive T Lymphocytes Catalytic Antibodies Cell Fractionation Cell Line Class Coitus Condition Development Drug Formulations Environment Excipients HIV HIV Envelope Protein gp120 HIV Seropositivity Immune Immunization Immunoglobulin A Immunoglobulin G In Vitro Infection Local Microbicides Lupus Lymphocyte Macaca Modeling Molecular Patients Phase Property Prophylactic treatment Rate Reaction Risk Salivary Serum Sexual Transmission Simulate Site Specificity Superantigens Vagina Variant analog base catalyst cost desire env Gene Products improved in vivo microbicide novel pandemic disease peptide analog polyclonal antibody resistance factors

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项目摘要

DESCRIPTION (provided by applicant): A specific, irreversible and cost-effective topical microbicide for HIV prophylaxis will help slow sexual transmission of the pandemic. Here, we propose the development of catalytic antibodies capable of degrading the HIV envelope protein gp120 as candidate HIVcides. The promising features of the antibodies are the permanent destruction of the envelope protein, reuse of a single catalyst molecule to degrade thousands of gp120 molecules and the recognition of a conserved gp120 region, the superantigen region, permitting neutralization of diverse HIV strains. Polyclonal antibody studies from uninfected and HIV infected subjects indicated that high level proteolytic and HIV neutralizing activities is a noteworthy property of IgA class antibodies. In the R21 project phase, characterization of our existing antibodies and their single chain Fv (scFv), IgA and IgG variants is proposed. The existing antibodies were obtained as IgGs by immunization with an electrophilic gp120 analog that induces antibodies with enhanced nucleophilic reactivity, a prerequisite for the catalytic reaction. Using an electrophilic probe to the gp120 superantigen site, additional proteolytic antibodies were obtained as scFv constructs cloned from the immune repertoire of lupus patients, who tend to produce antibodies with proteolytic activity directed to the gp120 superantigen site. The antibodies will be characterized with respect to HIV degrading efficiency; specificity, potency and breadth of HIV neutralization; and the ability to perform these functions in the vaginal milieu. To isolate novel, improved antibodies, we will screen the proteolytic and HIV neutralizing activity of salivary and serum IgAs from HIV-negative and HIV-positive subjects in the R21 project phase. In the R33 phase, monoclonal IgAs with the desired properties will be cloned from lymphocytes by cell-fractionation based on covalent binding of an electrophilic gp120 peptide analog, a property associated with proteolytic antibody-producing cells. Proof-of-principle for in vivo antibody efficacy will be obtained in the R33 phase using the SHIV-macaque model of infection. The Abs will also be examined for activity in vitro as microbicide excipient formulations under conditions simulating the vaginal environment following sexual intercourse. These studies may identify proteolytic antibodies suitable for further development as a topical HIVcide.

描述（由申请人提供）：一种特定的，不可逆的且具有成本效益的局部杀伤力型艾滋病毒预防，将有助于减慢大流行的性传播。在这里，我们提出了能够将HIV包膜蛋白GP120降解为候选Hivcides的催化抗体的发展。抗体的有前途的特征是包膜蛋白的永久破坏，重复使用单个催化剂分子以降解数千个GP120分子，并识别保守的GP120区域，即超基因区域，允许对多种HIV菌株进行中和。来自未感染和HIV感染受试者的多克隆抗体研究表明，高水平的蛋白水解和HIV中和活性是IGA类抗体的一个值得注意的特性。在R21项目阶段，提出了我们现有抗体及其单链FV（SCFV），IgA和IgG变体的表征。现有的抗体是通过用亲电的GP120类似物免疫来作为IgGs获得的，该抗体诱导具有增强的亲核反应性的抗体，这是催化反应的先决条件。使用对GP120超抗原位点的亲电探针，作为从狼疮患者的免疫库中克隆的SCFV构建体获得了其他蛋白水解抗体，这些型狼疮患者倾向于产生针对GP120超抗原的蛋白水解活性的抗体。抗体将以艾滋病毒降解效率为特征。艾滋病毒中和的特异性，效力和广度；以及在阴道环境中执行这些功能的能力。为了隔离新颖的，改进的抗体，我们将在R21项目阶段筛选出HIV阴性和HIV阳性受试者的唾液和血清IGA的蛋白水解和HIV中和活性。在R33阶段，具有基于细胞分级的淋巴细胞基于亲电GP120肽类似物的共同结合，从淋巴细胞中克隆了所需特性的单克隆IGA，这是一种与蛋白水解抗体产生的细胞相关的特性。使用Shiv-Macaque感染模型，将在R33期获得体内抗体功效的原则证明。在模拟性交后模拟阴道环境的条件下，还将检查ABS在体外的活性，作为杀菌剂赋形剂制剂。这些研究可能鉴定出适合进一步发育的蛋白水解抗体。