A Propagating Chimeric Particle as a Safe Alternative to Live-Attenuated Virus

传播嵌合粒子作为减毒活病毒的安全替代品

• 批准号: 7713896
• 负责人: KELLY Y. POE
• 金额: $ 18.86万
• 依托单位: GLOBAL VACCINES, INC.
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-08-01 至 2011-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7713896
• 关键词: Acquired Immunodeficiency Syndrome; Adverse effects; Animal Model; Animals; Antibodies; Antigens; Attenuated; Attenuated Live Virus Vaccine; Biological Assay; Blood Circulation; Brain; Breeding; CD4 Positive T Lymphocytes; Capsid; Cell Count; Cells; Clinical; Communities; Complete Blood Count; DNA; Development; Dose; Drug resistance; Environment; Enzyme-Linked Immunosorbent Assay; Exposure to; Fetal Liver; Gag PR; Gagging; Genetic Materials; Genetic Recombination; Genome; Genomics; Goals; Gold; HIV; HIV Antigens; HIV Envelope Protein gp120; HIV Infections; HIV vaccine; HIV-1; HIV-1 vaccine; Hamsters; Hematopoietic stem cells; Highly Active Antiretroviral Therapy; Histopathology; Human; IgG1; Immune System Diseases; Immune response; Immunity; Immunoglobulin G; Immunoglobulin M; In Vitro; Inbred BALB C Mice; Individual; Infection; Integrase; Interferon Type I; Interferon Type II; Interferons; Intestines; Kinetics; Life; Life Cycle Stages; Light; Liver; Logistics; Longevity; Lung; Lytic; Macaca; Mediating; Methods; Modeling; Monkeys; Mus; Nature; Nucleocapsid; Organ; Particulate; Pathology; Peptides; Peripheral Blood Mononuclear Cell; Pilot Projects; Plasma; Production; Proteins; Quality of life; RNA; Reagent; Recombinants; Research; Route; SIV; SIV protease; Safety; Serum; Site; Spleen; Splenocyte; Structural Protein; Subfamily lentivirinae; Symptoms; System; Time; Toxic effect; Transgenic Organisms; Translations; United States National Institutes of Health; Universities; Vaccinated; Vaccination; Vaccines; Venezuelan Equine Encephalitis Virus; Viral; Virion; Virus; Virus Diseases; Virus-like particle; Weight; base; cytokine; exposed human population; immunogenic; immunogenicity; lymph nodes; mouse model; neutralizing antibody; nonhuman primate; novel; novel strategies; particle; pre-clinical; programs; prototype; public health relevance; reconstitution; replicase; research and development; research study; response; simian human immunodeficiency virus; vaccine development; vaccine safety; vector

DESCRIPTION (provided by applicant): Although the use of highly active anti-retroviral therapy (HAART) has enhanced both the longevity and quality of life for HIV-infected individuals by controlling viral replication, financial and logistic drawbacks as well as clinical side effects and the development of drug resistance limits its worldwide use. Subsequently, the development of a safe yet effective vaccine for HIV remains the long term goal for both scientific and political communities worldwide. In light of this observation, the overall objective of this research is to develop a vaccine against HIV that combines the superior and long-lived immunity of a live-attenuated virus (LAV) with the safety of a nonreplicating particulate antigen to generate a novel, acutely-propagating chimeric particle (PCP) vaccine. These chimeric particles contain a replicating VEE/SHIV genome and are capable of infecting susceptible cells bearing hCD4/hCCR5, undergoing cytoplasmic replication, genomic RNA encapsidation, assembly, and particle release. The VEE-SHIV PCP does not contain the HIV LTRs or integrase therefore increasing the general safety of the vaccine. Due to the replicative nature of these particles, lentiviral proteins will be expressed for an extended period of time in vaccinated individuals thus inducing a more comprehensive immune response compared to nonreplicating antigens. Furthermore, the chimeric particle has an inherent safety feature; the VEE replicase machinery is sensitive to interferon thus limiting the replication until the immune response to the lentiviral proteins clears the virus. Another advantage of the VEE-SHIV PCP vaccine compared to LAV is that lentiviral structural proteins are combined with the replicase machinery from VEE, thus eliminating replication restrictions seen with wild-type lentiviruses in murine cells. Therefore, unlike wild-type lentiviruses, the VEE-SHIV PCP is infectious in the presence or absence of particle maturation and can efficiently replicate in murine cells without limitation. The main objectives of this proposal are to: 1) vaccinate hCD4/hCCR5 transgenic (hCD4/R5 Tg) and BALB/c Rag2-/-, c-/- mice reconstituted with human hematopoietic stem cells from human fetal liver (huDKO) with purified chimeric particles and DNA expressing the VEE-SHIV PCP, 2) demonstrate replication of the VEE-SHIV PCP, 3) assess safety, and 4) evaluate the immunogenicity of the PCP vaccine in hCD4/R5 Tg and huDKO mouse models. Overall, the propagating chimeric particle vaccine strategy is expected to be a safe alternative to live-attenuated vaccines in the quest for a safe, yet effective vaccine against HIV-1/AIDS. PUBLIC HEALTH RELEVANCE: Although the immunity induced by live-attenuated virus is the gold standard for HIV-1 vaccine development, safety concerns preclude their use in humans. Therefore, a VEE-SHIV propagating chimeric particle (PCP) vaccine is proposed as a safe alternative to live-attenuated virus. This prototype chimeric particle vaccine contains lentiviral structural proteins to elicit HIV-specific immunity, and the replicase machinery of VEE to permit replication in BALB/c transgenic hCD4/hCCR5 and BALB/c Rag2-/-, c-/- mice reconstituted with human hematopoietic stem cells from human fetal liver (huDKO) mouse models of HIV infection described in this application, as well as humans and non-human primates.

描述（由申请人提供）：尽管高效抗逆转录病毒疗法（HAART）的使用通过控制病毒复制提高了艾滋病毒感染者的寿命和生活质量，但财务和后勤方面的缺陷以及临床副作用和耐药性的发展限制了其在全球范围内的使用。因此，开发安全有效的艾滋病毒疫苗仍然是全世界科学界和政治界的长期目标。鉴于这一观察结果，本研究的总体目标是开发一种抗 HIV 疫苗，将减毒活病毒 (LAV) 的卓越且长效的免疫力与非复制颗粒抗原的安全性结合起来，产生一种新型的、急性传播的嵌合颗​​粒 (PCP) 疫苗。这些嵌合颗粒含有复制的 VEE/SHIV 基因组，能够感染带有 hCD4/hCCR5 的易感细胞，经历细胞质复制、基因组 RNA 衣壳化、组装和颗粒释放。 VEE-SHIV PCP 不含 HIV LTR 或整合酶，因此提高了疫苗的总体安全性。由于这些颗粒的复制性质，慢病毒蛋白将在接种疫苗的个体中表达较长时间，从而与非复制抗原相比诱导更全面的免疫反应。此外，嵌合颗粒具有固有的安全特性； VEE 复制酶机制对干扰素敏感，从而限制复制，直到对慢病毒蛋白的免疫反应清除病毒。与 LAV 相比，VEE-SHIV PCP 疫苗的另一个优点是慢病毒结构蛋白与 VEE 的复制酶机制相结合，从而消除了野生型慢病毒在小鼠细胞中的复制限制。因此，与野生型慢病毒不同，VEE-SHIV PCP 在颗粒成熟或不成熟的情况下都具有感染性，并且可以在小鼠细胞中无限制地有效复制。该提案的主要目标是：1) 对 hCD4/hCCR5 转基因 (hCD4/R5 Tg) 和 BALB/c Rag2-/-, c-/- 小鼠进行疫苗接种，这些小鼠是用来自人胎肝 (huDKO) 的人造血干细胞 (huDKO) 重建的，并带有纯化的嵌合颗粒和表达 VEE-SHIV PCP 的 DNA，2) 证明 VEE-SHIV 的复制 PCP，3) 评估安全性，4) 评估 PCP 疫苗在 hCD4/R5 Tg 和 huDKO 小鼠模型中的免疫原性。总体而言，在寻求安全而有效的 HIV-1/AIDS 疫苗过程中，繁殖嵌合颗粒疫苗策略有望成为减毒活疫苗的安全替代方案。公共卫生相关性：虽然减毒活病毒诱导的免疫力是 HIV-1 疫苗开发的黄金标准，但出于安全考虑，它们无法用于人类。因此，VEE-SHIV 传播嵌合颗粒 (PCP) 疫苗被提议作为减毒活病毒的安全替代品。这种原型嵌合颗粒疫苗含有慢病毒结构蛋白，可引发 HIV 特异性免疫，而 VEE 复制酶机制可在 BALB/c 转基因 hCD4/hCCR5 和 BALB/c Rag2-/-、c-/- 小鼠中进行复制，这些小鼠是用来自人胎肝 (huDKO) 小鼠 HIV 模型的造血干细胞重建的 本申请中描述的感染，以及人类和非人类灵长类动物。