Targeting Pneumococcal Colonization

针对肺炎球菌定植

基本信息

批准号：
10113534
负责人：
Jeffrey Neal Weiser
金额：
$ 21.19万
依托单位：
NEW YORK UNIVERSITY SCHOOL OF MEDICINE
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-03-01 至 2023-02-28
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10113534
关键词：
Address Adjuvant Adult Affect Age Anabolism Animals Antibodies Antibody Response Antigen Targeting Antigens Biology Cell Wall Cell surface Child Data Set Development Disease Enzymes Extracellular Protein Fibrinogen Formulation Future Genes Genetic Screening Genome Glycoconjugates Growth Human Immune Immunity Immunization Immunize Infant Infection Interruption Laboratories Licensing Maintenance Metabolism Modeling Mucosal Immunity Mucous Membrane Mus Mutagenesis N-acetylglucosamine deacetylase Neuraminidase Organism Pathogenesis Penicillin-Binding Proteins Peptide Hydrolases Phosphorylcholine Pneumococcal Colonization Pneumococcal Infections Polysaccharides Population Prevalence Prevention Prevention strategy Protein Kinase Proteins Public Health Recombinant Proteins Recombinants Respiratory System Serotyping Source Streptococcus pneumoniae Surface Surface Antigens Technology Teichoic Acids Testing Upper respiratory tract Vaccination Vaccines Variant base contagion cross reactivity esterase experience immunogenic in vitro Assay member mouse model murine antibody mutant novel novel strategies pressure prevent protein function pup transmission process transposon sequencing vaccine development vaccine discovery

项目摘要

Streptococcus pneumoniae (Spn, the pneumococcus) remains a leading cause of respiratory tract and invasive infection. While vaccination with capsular polysaccharide-based vaccines has decreased the high burden of Spn disease, this approach fails to target the majority of Spn, which are non-vaccine serotypes. Unfortunately, the development of more broadly-acting, serotype- independent vaccines that focus on preventing Spn disease has proven to be elusive. The required first step for Spn-host interaction, however, is colonization of the mucosal surfaces of the upper airways. Our premise is that interrupting colonization will have the greatest overall impact on Spn disease and offers new, unexplored possibilities for prevention. We have optimized an infant mouse model of Spn colonization that has allowed the application of Tn-Seq transposon mutagenesis to interrogate the entire Spn genome to identify loci affecting colonization. The complete dataset of non-essential Spn genes affecting colonization was then compared to bacterial surface factors that are immunogenic during human infection. Defined mutants in each of these candidates were constructed and tested in both infant and adult murine models of colonization. Seven loci expressing proteins of known function that modify the bacterial surface or host substrates were validated as required for efficient colonization. These proteins are all members of the Spn core genome present in all strains and show minimal sequence variation across isolates. Our hypothesis is that immunity to these candidates, alone or in combination, will interrupt Spn colonization. This hypothesis will be tested first by immunization with recombinant protein in adjuvant (SC or IN) to maximize antibody responses. Murine antibody will be used to confirm surface localization and to explore its ability to block protein function using in vitro assays. Immune mice v. adjuvant alone controls will then be challenged IN or via pup-to-pup transmission to assess protection from colonization with diverse strains. In future studies, candidates validated in the murine model can be investigated using experimental human pneumococcal carriage to bridge the critical step from animal to human testing. Thus, our proposal takes a novel approach, targeting colonization, to the ongoing public health problem of the pneumococcus.

肺炎链球菌（Spn，肺炎球菌）仍然是呼吸道的主要原因和侵袭性感染。虽然接种荚膜多糖疫苗已减轻了 Spn 疾病的高负担，但这种方法未能针对大多数 Spn，这是非疫苗血清型。不幸的是，更广泛作用的血清型的开发事实证明，专注于预防 Spn 疾病的独立疫苗是难以捉摸的。这然而，Spn-宿主相互作用所需的第一步是在粘膜表面定植上呼吸道。我们的前提是，中断殖民化将带来最大的整体效果。对 Spn 疾病的影响并提供新的、未经探索的预防可能性。我们已经优化了允许应用 Tn-Seq 转座子的 Spn 定植婴儿小鼠模型诱变来询问整个 Spn 基因组，以确定影响定植的基因座。这然后将影响定植的非必需 Spn 基因的完整数据集与在人类感染期间具有免疫原性的细菌表面因子。每个中定义的突变体这些候选者是在婴儿和成年小鼠模型中构建和测试的殖民化。七个基因座表达具有已知功能的修饰细菌表面的蛋白质或宿主底物根据有效定植的需要进行验证。这些蛋白质都是 Spn 核心基因组的成员存在于所有菌株中，并且显示出最小的序列变异跨隔离群。我们的假设是，对这些候选人的免疫力，单独或组合，将中断 Spn 定植。该假设将首先通过重组免疫来检验佐剂（SC 或 IN）中的蛋白质可最大限度地提高抗体反应。鼠源抗体将用于使用体外测定确认表面定位并探索其阻断蛋白质功能的能力。然后，免疫小鼠与单独佐剂对照将受到挑战或通过幼仔间传播评估对不同菌株定植的保护作用。在未来的研究中，候选人验证了在小鼠模型中，可以使用实验性人类肺炎球菌携带来研究连接从动物测试到人体测试的关键步骤。因此，我们的建议采用了一种新颖的方法，针对肺炎球菌定植，解决持续存在的公共卫生问题。