SARS-CoV S Protein Receptor-binding Domain-based Vaccines

SARS-CoV S 蛋白受体结合域疫苗

• 批准号: 7261583
• 负责人: SHIBO JIANG
• 金额: $ 37.01万
• 依托单位: NEW YORK BLOOD CENTER
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-03-15 至 2011-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7261583
• 关键词: Adjuvant; Adult; Adverse effects; Alanine; Animals; Antibodies; Antibody Formation; Binding; Biological; Bioterrorism; CD4 Positive T Lymphocytes; Calorimetry; Canada; Cells; Chimeric Proteins; China; Cleaved cell; Clinic; Clinical Research; Clinical Trials; Codon Nucleotides; Collaborations; Coronavirus; Cysteine; Development; Disease Outbreaks; Dose; Endopeptidases; Enzyme-Linked Immunosorbent Assay; Enzymes; Epidemic; Epitopes; Escherichia coli; Excision; Exhibits; Ferrets; Flow Cytometry; Future; Genes; Goals; Health; Helper-Inducer T-Lymphocyte; High Pressure Liquid Chromatography; Human; Immune response; Immunity; Immunization; Inbred BALB C Mice; Infection; Infection prevention; Inflammatory; Injection of therapeutic agent; Intramuscular; Laboratories; Length; Liver; Lung; MF59; Microbiology; Modeling; Molecular Conformation; Mus; Organ; Oryctolagus cuniculus; Patients; Peptide Hydrolases; Phase; Populations at Risk; Production; Proteins; RNA Recognition Motif; Reaction; Readiness; Recombinant Proteins; Recombinants; Reporting; Research Personnel; Route; Safety; Serum; Severe Acute Respiratory Syndrome; Solubility; Structure; Subunit Vaccines; System; Testing; Titrations; Treatment Protocols; Vaccines; Vaccinia Vaccine; Viral; Virus Replication; Viverridae; Week; Yeasts; aged; aluminum sulfate; base; biodefense; disulfide bond; expression vector; improved; in vivo; neutralizing antibody; pathogen; pre-clinical; prevent; programs; protein expression; receptor binding; response; subcutaneous; vaccine efficacy; vector

DESCRIPTION (provided by applicant): Severe acute respiratory syndrome (SARS)-associated coronavirus (SARS-CoV), an emerging infectious pathogen, caused a global outbreak in 2002-2003. Though it is under control, it may cause future epidemics and may be utilized by bioterrorists to attack innocent people. Therefore, it is essential to develop effective and safe vaccines for preventing future SARS outbreaks and for biodefense preparedness. Currently, most SARS vaccines under development consist of inactivated SARS-CoV or its full-length spike (S) protein. Concerns have been raised about the safety and efficacy of these vaccines since they may induce harmful immune responses or inflammatory reactions. We previously demonstrated that the receptor-binding domain (RBD), a small fragment in the S protein S1 domain responsible for SARS-CoV attachment, fusion and entry into the target cell contains multiple conformational epitopes that elicit highly potent neutralizing antibody responses and protective immunities against the SARS-CoV strains isolated from patients in 2002-2003 and 2003-2004 SARS epidemics and those from palm civets. Since RBD sequences in the S proteins of all SARS-CoV isolates identified so far exhibit more than 95% homology, we thus hypothesize that a recombinant RBD (rRBD) cloned and expressed in E. coli or yeast may elicit cross-neutralizing antibody responses and protective immunities against a majority of SARS-CoV strains that may cause future SARS outbreaks. Therefore, rRBD can be used as a subunit vaccine to protect people from SARS-CoV infection and prevent future SARS epidemics. The specific aims of this proposal are: (1) to express, purify and characterize rRBD of the SARS-CoV strains Tor2 and GD03T13 produced in E. coli or yeast. We will undertake a major effort in developing new strategies to enhance the yield and solubility of rRBD expressed in E. coli since E. coli remains the most preferable system for expressing large quantities of recombinant proteins for future preclinical and clinical studies. If it is proven that E. coli is not suitable for expression of rRBD, we will test yeast and other expression systems until an ideal expression system for production of rRBD is identified. Only the rRBD with proper antigenic conformation and biological activity will be selected for further study; (2) to assess the rRBD-induced antibodies against 3 representative SARS-CoV isolates; (3) to optimize the immunization regimens by selecting proper adjuvants, administration routes, and rRBD doses; and (4) to evaluate the in vivo efficacy and safety of the selected rRBD in mouse and ferret models. The long-term goal of this project is to develop highly effective and safe subunit vaccines for protecting at-risk populations from SARS-CoV infection or bioterrorism attack.

描述（由申请人提供）：严重急性呼吸综合征（SARS）相关冠状病毒（SARS-CoV）是一种新出现的传染性病原体，于 2002-2003 年引起全球爆发。尽管它已得到控制，但它可能会导致未来的流行病，并可能被生物恐怖分子用来攻击无辜者。因此，开发有效且安全的疫苗来预防未来 SARS 爆发和生物防御准备至关重要。目前，大多数正在开发的 SARS 疫苗由灭活的 SARS-CoV 或其全长刺突 (S) 蛋白组成。人们对这些疫苗的安全性和有效性表示担忧，因为它们可能会诱发有害的免疫反应或炎症反应。我们之前证明，受体结合结构域（RBD）是S蛋白S1结构域中负责SARS-CoV附着、融合和进入靶细胞的小片段，它包含多个构象表位，可引发高效的中和抗体反应和保护性免疫针对 2002-2003 年和 2003-2004 年 SARS 流行病患者以及果子狸中分离出的 SARS-CoV 毒株。由于迄今为止鉴定的所有 SARS-CoV 分离株的 S 蛋白中的 RBD 序列表现出超过 95% 的同源性，因此我们假设在大肠杆菌或酵母中克隆和表达的重组 RBD (rRBD) 可能会引发交叉中和抗体反应，针对大多数可能导致未来 SARS 爆发的 SARS-CoV 病毒株的保护性免疫。因此，rRBD可以作为亚单位疫苗来保护人们免受SARS-CoV感染并预防未来的SARS流行。该提案的具体目标是：（1）表达、纯化和表征大肠杆菌或酵母中产生的 SARS-CoV 菌株 Tor2 和 GD03T13 的 rRBD。我们将大力开发新策略，以提高大肠杆菌中表达的 rRBD 的产量和溶解度，因为大肠杆菌仍然是表达大量重组蛋白用于未来临床前和临床研究的最优选系统。如果证明大肠杆菌不适合表达rRBD，我们将测试酵母和其他表达系统，直到找到生产rRBD的理想表达系统。只有具有适当抗原构象和生物活性的rRBD才会被选择进行进一步研究； (2) 评估 rRBD 诱导的针对 3 种代表性 SARS-CoV 分离株的抗体； (3)通过选择合适的佐剂、给药途径和rRBD剂量来优化免疫方案； (4) 评估所选 rRBD 在小鼠和雪貂模型中的体内功效和安全性。该项目的长期目标是开发高效、安全的亚单位疫苗，以保护高危人群免受SARS-CoV感染或生物恐怖袭击。