MODULAR CHIMERIC VACCINES TAILORED FOR MALARIA PARASITES

针对疟疾寄生虫的模块化嵌合疫苗

• 批准号: 8172410
• 负责人: Alberto Moreno
• 金额: $ 5.48万
• 依托单位: EMORY UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-05-01 至 2011-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8172410
• 关键词: Anemia; Antibodies; Antigens; Autologous; B-Lymphocyte Epitopes; Chimera organism; Chimeric Proteins; Codon Nucleotides; Complex; Computer Retrieval of Information on Scientific Projects Database; Data; Epitopes; Erythrocytes; Escherichia coli; Exhibits; Funding; Generations; Grant; Hybrids; Immunity; Institution; Link; Malaria; Malaria Vaccines; Merozoite Surface Protein 1; Mus; Parasitemia; Parasites; Peptides; Protein Fragment; Proteins; Recombinant Proteins; Recombinants; Reporting; Research; Research Design; Research Personnel; Resources; Source; Staging; Structure; Synthetic Genes; System; T cell response; T-Lymphocyte Epitopes; United States National Institutes of Health; Vaccines; base; comparative; design; immunogenicity; improved; polypeptide; protective efficacy; research study; vaccine candidate

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. We have reported proof of principle studies designed to determine the potential of multimeric polypeptides as a delivery system for pre-erythrocytic malaria vaccines. The first generation of polypeptide chimeras, which we have called linear peptide chimeras (LPC), was designed to include linear sequences representing well-characterized pre-erythrocytic B cell epitopes. Structural analyses of several erythrocytic stage vaccine candidates revealed that protective antibodies predominantly recognize functional domains that exhibit complex tertiary structure. To confirm that our strategy to improve immunogenicity of malaria vaccine candidates can also be used for non-linear structured domains, we designed P. yoelii chimeric recombinant protein comprising autologous promiscuous T cell epitopes assembled in tandem and linked to carboxyl terminal domain of well-characterized merozoite surface protein 1 known as PyMSP119. The synthetic gene was codon-optimized for expression in E. coli and the recombinant product, that we have called Recombinant Modular Chimera (RMC), used for comparative experiments of immunogenicity and protective efficacy with control protein that only included PyMSP119 protein fragment. The inclusion of autologous T cell epitopes did not alter the integrity of the recombinant product. Relevantly, T cell epitopes were successfully expressed and able to induce epitope-specific T cell responses. RMC generated robust protection to both hyper-parasitemia and severe anemia after experimental challenge with homologous P. yoelii strain. Most importantly, we found that RMC induced functional antibodies that protected against heterologous challenge more efficiently than antibodies induced by control protein. Based on experimental evidence that P. yoelii pre-erythrocytic (LPC) and erythrocytic stage (RMC) recombinant chimeric proteins induced protective immunity, we decided to evaluate the potential synergistic effect of combining LPC and RMC in a single immunogen. We created a hybrid synthetic gene encoding an amino-terminal pre-erythrocytic LPC and a carboxyl terminal erythrocytic RMC. Preliminary data indicate that such hybrid vaccine is able to induce sterilizing immunity in mice.

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 我们已经报道了设计用于确定多聚体多肽作为红细胞前疟疾疫苗的递送系统的潜力的原理研究的证据。我们称之为线性肽嵌合体（LPC）的第一代多肽嵌合体被设计为包括代表充分表征的红细胞前B细胞表位的线性序列。几种红细胞期候选疫苗的结构分析显示，保护性抗体主要识别表现出复杂三级结构的功能结构域。 为了证实我们改善疟疾疫苗候选物的免疫原性的策略也可以用于非线性结构化结构域，我们设计了约氏疟原虫嵌合重组蛋白，其包含串联组装的自体混杂T细胞表位，并连接至被称为PyMSP 119的充分表征的裂殖子表面蛋白1的羧基末端结构域。对合成基因进行密码子优化以在E.大肠杆菌和重组产物，我们称之为重组模块嵌合体（RMC），用于免疫原性和 与仅包括PyMSP 119蛋白片段的对照蛋白相比的保护效力。 包含自体T细胞表位并不改变重组产物的完整性。相关地，T细胞表位被成功表达并且能够诱导表位特异性T细胞应答。在用同源约氏疟原虫菌株进行实验性攻击后，RMC对高寄生虫血症和严重贫血都产生了强大的保护作用。最重要的是，我们发现RMC诱导的功能性抗体比对照蛋白诱导的抗体更有效地保护免受异源攻击。根据实验证据，约氏疟原虫红细胞前 (LPC)和红细胞期（RMC）的重组嵌合蛋白诱导的保护性免疫，我们决定评估在单一免疫原中组合LPC和RMC的潜在协同效应。我们创建了一个混合的合成基因编码的氨基末端前红细胞LPC和羧基末端红细胞RMC。初步数据表明，这种杂交疫苗能够在小鼠中诱导绝育免疫。