CONSERVED NEISSERIA PROTEINS AS VACCINE CANDIDATES

作为候选疫苗的保守奈瑟菌蛋白

• 批准号: 6195293
• 负责人: Dan M. Granoff
• 金额: $ 49.75万
• 依托单位: CHILDREN'S HOSPITAL & RES CTR AT OAKLAND
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-07-05 至 2003-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6195293
• 关键词: Neisseria meningitidis; Neisseria meningitidis vaccine; active immunization; antibacterial antibody; antibody formation; bacterial antigens; bacterial proteins; guinea pigs; laboratory mouse; laboratory rat; monoclonal antibody; vaccine development

DESCRIPTION: (Adapted from Applicant's Abstract) The long-term objective of this study is to increase our understanding of the use of conserved membrane proteins as components of a vaccine for prevention of Neisseria meningitidis serogroup B (MenB) disease. MenB is a major cause of meningitis and sepsis. Although serum bactericidal antibodies confer protection, to date, conventional approaches to develop a vaccine have been largely unsuccessful. Polysaccharide-based MenB vaccines risk eliciting autoantibodies to host polysialic acid, while the ability of most non-capsular antigens to elicit broad-based immunity is limited by antigenic diversity. We propose to investigate the vaccine potential of three recently discovered conserved Neisserial membrane proteins, designated Neisserial surface proteins (Nsp) A, B, and C. As backup candidates, NspD and NspE are also available. NspA was discovered with a monoclonal antibody, while the other four proteins represent new vaccine candidates that were discovered from analysis of genomic data. All five proteins are highly conserved across pathogenic Neisseria, have epitopes on the surface of the bacteria that are accessible to antibody, and elicit complement-mediated bactericidal antibodies in mice or rabbits. Thus, each of these proteins deserves further investigation as candidate antigens for inclusion in a MenB vaccine. In Aim 1, we will investigate the immunogenicity of each of the recombinant proteins in mice and guinea pigs. Should the recombinant molecules fail to elicit high titers of antibodies that are functionally active against the bacteria, we will attempt to reconstitute conformational epitopes with the use of detergents or liposomes, and explore the use of novel adjuvants suitable for human use. In Aim 2, we will prepare monoclonal antibodies (Mabs) that react with epitopes on the Ns proteins that are important in eliciting protective antibodies. These Mabs will be used for epitope mapping, and for studies of antibody functional activity. In Aim 3, we also will use the 3Iabs to investigate whether there are strain differences in surface accessibility and expression of the different NS proteins, and correlate any differences found with the respective DNA sequences encoding the proteins, or transcriptional activity of the respective genes. We also will investigate whether surface accessibility of the different Ns proteins varies within a Neisserial strain when propagated in vitro, or in infant rats. In Aim 4, we will test the hypothesis that a vaccine containing more than one Ns protein will elicit broader protective immunity to MenB than a vaccine made from a single protein. These results are directly relevant to evaluating the potential for inclusion or exclusion of each of these novel proteins in a MenB vaccine. The data also may validate the genomic approach for identification of new antigenic targets for vaccine development.

描述：（改编自申请人的摘要）长期目标 这项研究是为了增加我们对保守膜的使用的了解 蛋白质作为预防脑膜炎奈瑟菌疫苗的成分 B 血清群 (MenB) 疾病。 MenB 是脑膜炎和败血症的主要原因。 尽管血清杀菌抗体可以提供保护，但迄今为止，传统的杀菌抗体 开发疫苗的方法基本上不成功。 基于多糖的 MenB 疫苗有引发宿主自身抗体的风险 聚唾液酸，而大多数非荚膜抗原能够引发 广泛的免疫受到抗原多样性的限制。我们建议 研究最近发现的三种保守基因的疫苗潜力 奈瑟氏菌膜蛋白，指定为奈瑟氏菌表面蛋白（Nsp）A， B 和 C。作为备用候选者，NspD 和 NspE 也可用。 NspA 是 用单克隆抗体发现的，而其他四种蛋白质代表 通过基因组数据分析发现的新候选疫苗。全部 五种蛋白质在致病性奈瑟菌中高度保守，具有表位 位于可接触抗体的细菌表面，并引发 小鼠或兔子体内补体介导的杀菌抗体。因此，每个 这些蛋白质值得进一步研究作为候选抗原 纳入 MenB 疫苗中。在目标 1 中，我们将研究免疫原性 小鼠和豚鼠体内的每种重组蛋白。应该 重组分子未能引发高滴度的抗体 具有对抗细菌的功能，我们将尝试重建 使用去污剂或脂质体来构建构象表位，并探索 使用适合人类使用的新型佐剂。在目标 2 中，我们将准备 单克隆抗体 (Mab) 与 Ns 蛋白上的表位发生反应， 对于引发保护性抗体很重要。这些单克隆抗体将用于 表位作图，以及用于抗体功能活性的研究。在目标 3 中，我们 还将使用 3Iabs 来研究是否存在应变差异 不同 NS 蛋白的表面可及性和表达，以及 将发现的任何差异与编码相应 DNA 序列相关联 蛋白质或相应基因的转录活性。我们也会 研究不同 Ns 蛋白的表面可及性是否不同 奈瑟氏菌菌株在体外繁殖时或在幼年大鼠中。瞄准 4、我们将检验以下假设：一种含有多个 N 的疫苗 蛋白质将引发比疫苗更广泛的 MenB 保护性免疫力 来自单一蛋白质。这些结果与评估直接相关 MenB 中包含或排除这些新蛋白质的潜力 疫苗。该数据还可以验证用于识别的基因组方法 疫苗开发的新抗原靶标。