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: 7895627
• 负责人: KELLY Y. POE
• 金额: $ 22.64万
• 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/7895627
• 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）：尽管使用高效抗逆转录病毒疗法（HAART）通过控制病毒复制提高了HIV感染者的寿命和生活质量，但财务和后勤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，开发一种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针对HIV的疫苗，该疫苗结合了减毒活病毒（LAV）的上级和长寿命的免疫力与非复制颗粒抗原的安全性，以产生一种新型的急性繁殖嵌合颗粒（PCP）疫苗。这些嵌合颗粒含有复制的VEE/SHIV基因组，并且能够感染携带hCD 4/hCCR 5的易感细胞，经历细胞质复制、基因组RNA降解、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的时间，从而诱导比非复制抗原更全面的免疫应答。此外，嵌合颗粒具有固有的安全特征; 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应答清除病毒。与LAV相比，VEE-SHIV PCP疫苗的另一个优点是慢病毒结构蛋白与来自VEE的复制酶机制组合，从而消除了在鼠细胞中野生型慢病毒的复制限制。因此，与野生型慢病毒不同，VEE-SHIV PCP在存在或不存在颗粒成熟的情况下都是感染性的，并且可以在鼠细胞中有效复制而不受限制。这项建议的主要目标是：1）接种hCD 4/hCCR 5转基因（hCD 4/R5 Tg）和BALB/c Rag 2-/-，c-/-小鼠，所述小鼠用来自人胎肝的人造血干细胞（huDKO）用纯化的嵌合颗粒和表达VEE-SHIV PCP的DNA重建，2）证明VEE-SHIV PCP的复制，3）评估安全性，以及4）在hCD 4/R5 Tg和huDKO小鼠模型中评估PCP疫苗的免疫原性。总体而言，在寻求安全而有效的抗HIV-1/AIDS疫苗的过程中，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：尽管减毒活病毒诱导的免疫力是HIV-1疫苗开发的金标准，但安全性问题阻碍了它们在人类中的使用。因此，VEE-SHIV增殖嵌合颗粒（PCP）疫苗被提议作为减毒活病毒的安全替代品。该原型嵌合颗粒疫苗含有慢病毒结构蛋白以引发HIV特异性免疫，以及VEE的复制酶机制以允许在BALB/c转基因hCD 4/hCCR 5和BALB/c Rag 2-/-，c-/-小鼠中复制，所述小鼠用来自本申请中描述的HIV感染的人胎肝（huDKO）小鼠模型的人造血干细胞重建，以及人和非人灵长类动物。