Small molecule protein-glycan inhib. as malaria transmission-blocking therapuetic

小分子蛋白聚糖抑制。

• 批准号: 8237055
• 负责人: Rhoel David Ramos Dinglasan
• 金额: $ 40.18万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-04-22 至 2014-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8237055
• 关键词: Acute; Adhesions; Affinity; Affinity Chromatography; Anabolism; Animals; Anopheles Genus; Anopheles gambiae; Antibodies; Antibody Specificity; Antigens; Antimalarials; Applications Grants; Back; Bacterial Adhesins; Basic Science; Binding; Binding Sites; Biological Assay; Biological Availability; Blocking Antibodies; Candidate Disease Gene; Carbohydrates; Cell surface; Cells; Chemicals; Chondroitin; Chondroitin Sulfate Proteoglycan; Chondroitin Sulfates; Chronic; Complement; Complex; Computer Simulation; Concanavalin A; Crystallization; Crystallography; Culicidae; Data; Development; Disaccharides; Disease Progression; Dose; Drug Compounding; Drug Design; Drug Kinetics; Drug resistance; Enzyme-Linked Immunosorbent Assay; Enzymes; Exhibits; Face; Gene Targeting; Generations; Genes; Glycoconjugates; Glycosaminoglycans; Goals; Hepatocyte; Homology Modeling; Housing; Human; Immune Sera; Immunofluorescence Immunologic; In Vitro; Incubated; Individual; Invaded; Knock-out; Knowledge; Lead; Lectin; Length; Libraries; Lichen - organism; Life Cycle Stages; Ligands; Liquid Chromatography; Liver; Malaria; Mammals; Mass Spectrum Analysis; Mediating; Mediator of activation protein; Membrane; Methods; Midgut; Modeling; Modification; Molecular; Molecular Models; Molecular Target; Mus; Organelles; Oryctolagus cuniculus; Outsourced Services; Parasites; Pathway interactions; Peptides; Pharmaceutical Preparations; Pharmacodynamics; Plasmodium; Plasmodium berghei; Plasmodium falciparum; Play; Polymers; Polysaccharides; Population; Post-Translational Protein Processing; Preparation; Process; Production; Progress Reports; Property; Protein Array; Proteins; Proteoglycan; Proteomics; RNA Interference; Recombinant Proteins; Recombinants; Regimen; Research Project Grants; Roentgen Rays; Role; Route; Safety; Serum; Sporozoites; Staging; Staining method; Stains; Streptavidin; Structure; Surface; Surface Plasmon Resonance; System; Testing; Therapeutic; Tissues; Toxic effect; Transferase; Translational Research; Vaccines; Variant; Von Willebrand Factor A Domain; Work; absorption; analog; base; cellular microvillus; chondroitin sulfate glycosaminoglycan; circumsporozoite; design; feeding; glycosylation; homologous recombination; improved; in vivo; inhibitor/antagonist; insight; knockout gene; man; microbial; mimetics; molecular dynamics; molecular modeling; novel; parasite invasion; pathogen; polypeptide; pre-clinical; preclinical study; prevent; protein expression; research study; response; scaffold; small molecule; tandem mass spectrometry; transmission process; usnic acid; vaccine candidate; vector mosquito; xylosyltransferase

DESCRIPTION (provided by applicant): Malaria transmission entails development of the Plasmodium parasite in the mosquito. We have identified a critical interaction between an unknown ookinete lectin-like protein and a chondroitin sulfate glycosaminoglycan ligand on the mosquito midgut lumenal surface. We hypothesize that by disrupting this interaction through the use of small molecule inhibitors we can prevent parasite establishment in the mosquito and, subsequently, completely abrogate malaria transmission. This is a translational research grant proposal with the goal of taking our basic research understanding of Plasmodium-mosquito host interactions toward the development of novel highly potent malaria transmission-blocking therapeutics. Our first aim, the Complete molecular characterization of Plasmodium ookinete protein-midgut glycosaminoglycan interactions involves (1) identifying novel lectin-like ookinete molecules by glycan-affinity chromatography and mass spectrometry, (2) characterizing their functional role in vivo through the production of gene knockout parasites, (3) assessing their binding affinity for mosquito chondroitin glycosaminoglycans by protein array-surface plasmon resonance, and (3) gaining insight into the structure-function of the molecule(s) in complex with chondroitin glycosaminoglycan fragments and structural analogues by molecular modeling and x-ray crystallography. The second aim of the project, the Development of lead Plasmodium transmission-blocking glycan-mimetic compounds and assessment of their transmission-blocking potential involves identification of novel derivatives and analogues of our lead transmission-blocking compound, VS1 (a non-peptidyl polyvinylsulfonated polymer), which is a structural mimic of midgut chondroitin glycosaminoglycans and inhibits >95% of parasite development in the mosquito. To develop more potent structural analogs, we propose a four-tiered approach: (1) isolation of varying chain-lengths of the VS1 polymer, (2) derivitization of VS1 to enhance inhibitory activity and bioavailability, (3) derivitization of (+)-usnic acid, a polyphenolic compound from lichens, and (4) assessment of the utility of peptide mimotopes of mosquito chondroitin sulfate glycosaminoglycans as transmission-blocking vaccine targets. To help progress toward preclinical studies, the top candidate compounds from each approach will be analyzed for their pharmacokinetic and pharmacodynamic properties in animal and human serum models. Mosquitoes transmit the Plasmodium parasite from infected human hosts to uninfected individuals. By blocking a critical protein-glycan (carbohydrate) interaction between the parasite and the mosquito vector through the use of small inhibitory compounds (drugs) we prevent parasite establishment in the mosquito and effectively disrupt the transmission cycle of the malaria parasite. This strategy is especially important given that many current antimalarials and vaccine candidates still permit transmission of the parasite through the mosquito, moreover, our lead compound has added potential utility as a multi-stage antimalarial therapeutic since it also prevents sporozoite establishment in liver cells, the first step towards the progression of disease in humans.

描述（由申请人提供）：疟疾传播需要蚊子体内疟原虫的发育。我们已经确定了一个未知的动合子凝集素样蛋白和硫酸软骨素糖胺聚糖配体之间的蚊子中肠腔表面的关键相互作用。我们假设，通过使用小分子抑制剂破坏这种相互作用，我们可以防止寄生虫在蚊子中建立，随后完全消除疟疾传播。这是一项转化研究资助提案，目标是将我们对疟原虫-蚊子宿主相互作用的基础研究理解用于开发新型高效疟疾传播阻断疗法。我们的第一个目标，疟原虫动合子蛋白-中肠糖胺聚糖相互作用的完整分子表征，包括（1）通过聚糖亲和色谱和质谱鉴定新的凝集素样动合子分子，（2）通过产生基因敲除寄生虫来表征它们在体内的功能作用，（3）通过蛋白质阵列-表面等离子体共振评估它们对蚊子软骨素糖胺聚糖的结合亲和力，和（3）通过分子建模和X射线晶体学获得对与软骨素糖胺聚糖片段和结构类似物复合的分子的结构-功能的了解。该项目的第二个目标是开发主要的疟原虫传播阻断聚糖模拟化合物并评估其传播阻断潜力，涉及鉴定我们的主要传播阻断化合物VS 1（一种非肽基聚乙烯磺酸聚合物）的新型衍生物和类似物，它是中肠软骨素糖胺聚糖的结构模拟物，可抑制蚊子体内95%以上的寄生虫发育。为了开发更有效的结构类似物，我们提出了一种四层方法：（1）分离不同链长的VS 1聚合物，（2）衍生化VS 1以增强抑制活性和生物利用度，（3）衍生化（+）-松萝酸，一种来自地衣的多酚化合物，和（4）评估蚊子硫酸软骨素糖胺聚糖的肽模拟表位作为传播阻断疫苗靶标的效用。为了帮助临床前研究取得进展，将在动物和人血清模型中分析每种方法的最佳候选化合物的药代动力学和药效学特性。 蚊子将疟原虫从受感染的人类宿主传播给未受感染的个体。通过使用小的抑制性化合物（药物）阻断寄生虫和蚊子载体之间的关键蛋白质-聚糖（碳水化合物）相互作用，我们防止寄生虫在蚊子中建立并有效地破坏疟疾寄生虫的传播周期。考虑到目前许多抗疟药和候选疫苗仍然允许寄生虫通过蚊子传播，这种策略尤其重要，此外，我们的先导化合物还增加了作为多阶段抗疟治疗剂的潜在效用，因为它还可以防止子孢子在肝细胞中建立，这是人类疾病进展的第一步。