A novel live-attenuated Zika vaccine with a modified 5'UTR

一种带有改良 5UTR 的新型寨卡减毒活疫苗

• 批准号: 10730832
• 负责人: FENGWEI BAI
• 金额: $ 44.4万
• 依托单位: UNIVERSITY OF SOUTHERN MISSISSIPPI
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-05-26 至 2026-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10730832
• 关键词: 3' Untranslated Regions; 5' Untranslated Regions; Adult; Affect; American; Antibodies; Attenuated; Attenuated Vaccines; Birth; Body Weight decreased; CD8-Positive T-Lymphocytes; Cambodian; Capsid; Categories; Cells; Cellular Immunity; Central Nervous System; Clinical; Congenital Abnormality; Contracts; Culicidae; Data; Defect; Dose; Drops; Effectiveness; Enzymes; Epidemic; Exhibits; Female; Flavivirus; Genome; Goals; Guillain Barré Syndrome; Human; Human Bites; Immune; Immunity; Immunization; Inactivated Vaccines; Liver; Measures; Membrane; Meningoencephalitis; Microcephaly; Mississippi; Modification; Molecular; Mus; Mutation; Names; Neurons; Newborn Infant; Nonstructural Protein; Nucleotides; Open Reading Frames; Organ; Pathogenesis; Pathogenicity; Peptide Hydrolases; Peripheral; Polyproteins; Pregnancy; Production; Proteins; Public Health; RNA; Research; Safety; Spleen; Structure; Subunit Vaccines; Survival Rate; T cell response; Testis; Therapeutic; Time; Tissues; Translating; Translations; Universities; Vaccines; Vagina; Vero Cells; Viral; Viral Genome; Viral Load result; Viremia; ZIKA; ZIKV disease; ZIKV infection; Zika Virus; Zika virus vaccine; antagonist; attenuation; base; congenital zika syndrome; effectiveness evaluation; effector T cell; fetal; fitness; future outbreak; genetic approach; graduate student; insight; male; mouse model; neurovirulence; novel; novel strategies; postnatal; prevent; response; reverse genetics; safety assessment; training opportunity; transmission process; type I interferon receptor; undergraduate student; vaccine access; vaccine candidate; young adult

Summary Zika virus (ZIKV) is a mosquito-transmitted flavivirus that has caused devastating congenital Zika syndromes (CZS), including microcephaly, congenital malformation, and fetal demise in human newborns in the 2015 - 2016 epidemics. In addition, ZIKV infection can cause Guillain-Barré syndrome (GBS) and meningoencephalitis in adults. Currently, ZIKV pathogenesis is incompletely understood, and there is no approved therapeutic or vaccine available. Although the number of human Zika cases has dropped since 2017, ZIKV will likely become endemic, and a vaccine that can prevent CZS and adult Zika diseases remains urgently needed to prepare for future outbreaks. Our research group recently developed a new live-attenuated ZIKV strain (named Z7) by inserting a 50-RNA-nucleotides (nt) hairpin into the 5’ untranslated region (UTR) of a pre-epidemic ZIKV Cambodian strain, FSS13025, which is attenuated in neurovirulence, immune antagonism, and mosquito infectivity compared with the American epidemic isolates. Our preliminary data demonstrate that Z7 replicates efficiently and produces high titers in Vero cells without causing apparent cytopathic effects (CPE) or losing the insert sequence even after ten consecutive passages. Interestingly, we identified a mutation S1417A in NS2B protein in Z7 after the 7th passage, indicating Z7 may have adapted a fitness mutation through the passaging. Importantly, Z7 induces sterilizing immunity that completely prevents viremia after a challenge with a high dose of an American epidemic strain (PRVABC59) in mice. These results suggest that modification of ZIKV 5’UTR is a novel strategy to develop live-attenuated vaccine candidates for ZIKV and potentially for other flaviviruses. In this application, we will first characterize Z7-induced humoral and cell-mediated immunity in a mouse model (Specific Aim 1), and then evaluate the safety features of Z7 in mice (Specific Aim 2). In Specific Aim 3, we will determine the mechanisms of action of Z7 attenuation. We believe that this project is highly significant because it will characterize the immunity and safety of a novel live-attenuated ZIKV vaccine candidate, Z7, which was developed for the first time by introducing a hairpin loop into a viral 5’ UTR. In addition, this R15 project will also provide a valuable and unique training opportunity to both undergraduate and graduate students at the University of Southern Mississippi.

概括 寨卡病毒 (ZIKV) 是一种由蚊子传播的黄病毒，可导致毁灭性的先天性寨卡综合症 (CZS)，包括 2015 - 2016 年人类新生儿的小头畸形、先天畸形和胎儿死亡 此外，ZIKV 感染还可导致格林-巴利综合征 (GBS) 和脑膜脑炎。 目前，ZIKV 的发病机制尚不完全清楚，也没有批准的治疗或治疗方法。 尽管自 2017 年以来人类寨卡病例数量有所下降，但寨卡病毒很可能会成为流行病。 流行病，并且仍然迫切需要一种可以预防 CZS 和成人寨卡病的疫苗，以做好准备 我们的研究小组最近开发了一种新的减毒活寨卡病毒毒株（命名为 Z7）。 将 50 个 RNA 核苷酸 (nt) 发夹插入流行前 ZIKV 的 5' 非翻译区 (UTR) 柬埔寨毒株 FSS13025，其神经毒力、免疫拮抗作用和蚊虫作用均减弱 与美国流行病分离株相比，我们的初步数据表明 Z7 具有复制性。 有效地在 Vero 细胞中产生高滴度，而不会引起明显的细胞病变效应 (CPE) 或失去 即使在连续十次传代后插入序列，我们也在 NS2B 中发现了一个突变 S1417A。 第七次传代后，Z7 中出现了蛋白质，表明 Z7 可能通过传代适应了适应性突变。 重要的是，Z7 可诱导灭菌免疫，在高剂量攻击后完全预防病毒血症 这些结果表明，ZIKV 5’UTR 的修饰是在小鼠体内进行的。 开发 ZIKV 和其他黄病毒候选减毒活疫苗的新策略。 在本应用中，我们将首先在小鼠模型中表征 Z7 诱导的体液和细胞介导的免疫 （具体目标 1），然后评估 Z7 在小鼠中的安全性特征（具体目标 2），我们将在具体目标 3 中进行评估。 确定 Z7 衰减的作用机制 我们认为该项目非常重要，因为。 它将表征一种新型减毒活 ZIKV 候选疫苗 Z7 的免疫力和安全性，该疫苗已被 首次通过将发夹环引入病毒 5' UTR 中来开发此外，该 R15 项目还将。 为大学本科生和研究生提供宝贵且独特的培训机会 密西西比州南部。