COMBINED APPROACH TO BROADLY PROTECTIVE AIDS VACCINES: I

广泛保护性艾滋病疫苗的综合方法：I

• 批准号: 7716355
• 负责人: Shiu-Lok Hu
• 金额: $ 42.21万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-05-01 至 2009-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7716355
• 关键词: Adjuvant; Alphavirus; Animals; Antibodies; Antibody Formation; Antigens; Biological Assay; CD8B1 gene; Cells; Codon Nucleotides; Computer Retrieval of Information on Scientific Projects Database; Control Animal; DNA; DNA Vaccines; Dose; Family suidae; Funding; GP 140; Gagging; Generations; Goals; Grant; HIV Envelope Protein gp120; HIV-1; Immunity; Immunization; Infection; Institution; Interferon Type II; Length; MF59; Macaca; Measures; Plasma; Primate Lentiviruses; Proteins; Recombinants; Replicon; Research; Research Personnel; Resources; Rest; Role; SIV; Source; Staging; Sus scrofa; T-Lymphocyte; Tail; Tumor Necrosis Factor-alpha; United States National Institutes of Health; Vaccines; Vaccinia virus; Viral; Viral Load result; Viral Vector; Viremia; Virus; Week; cell mediated immune response; day; human TNF protein; neutralizing antibody; particle; plasmid DNA; pol genes; response; tissue culture; vector

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. Heterologous "prime-boost" immunization has been shown to elicit protective immunity against multiple primate lentiviruses, including SIVmne, SHIVIIIB and SHIV89.6P. However, there have been relatively few studies comparing the protective efficacy of different prime-boost combinations. The goal of this project is to examine "prime-boost" immunization strategies to identify combinations that induce antibody and CD8+ T cell-mediated immune responses against primate lentiviruses. In the first two stages of this study, we compared recombinant vaccinia virus or DNA vaccine for priming, followed by DNA, protein, or alphavirus boosting, for their ability to protect against mucosal challenge with a CCR5-using SHIVSF162 P4. Twenty-four pig-tailed macaques were primed either with recombinant vaccinia viruses expressing HIV-1 SF162 full length env and SIVmac239 gag/pol (Groups 1-3), or DNA plasmids expressing the same antigens (Groups 5-7). After a resting period, six animals per group were boosted twice (3 mos apart) with one of the following immunogens: Groups 1 and 5, DNA plasmids expressing codon-optimized SF162 env gp140, or SIVmac239 gag-pol, formulated in PBS; Groups 2 and 6, protein immunogens SIVmac239 Gag-Pol particles and SF162 Env gp140 protein formulated in MF59; or recombinant viral vectors expressing the same antigens (Group 3 with alpha virus replicons and Group 7 with vaccinia virus recombinants). Control animals received parental vaccinia virus for prime and empty vector or adjuvant only for boost. After the last immunization, animals in all experimental groups generated SIV- and HIV-specific antibody responses. Compared to animals in other experimental groups, animals boosted with proteins (Groups 2 and 6) had significantly higher SIV-specific and HIV-1-specific gp120 antibody titers, including homologous neutralization titers in a pseudotyped virus assay (p lt 0.001). Four weeks after the last immunization, all animals were challenged with 1,800 50% tissue culture infectious dose of SHIVSF162 P4 by intrarectal inoculation. SHIVSF162 P4 infection in pig-tailed macaques was robust, as shown by mean peak plasma viral of gt 10^7 copies/ml and persistent viremia in gt 1/3 of the animals. Significant reduction of mean plasma viral load was observed in all immunization groups (p lt 0.01 for Groups 2 and 6 vs controls; p lt 0.05 for all other groups). We also observed a significant inverse correlation (Spearman's r = -0.819, p lt 0.0001) between homologous neutralizing antibody (NtAb) titer on day of challenge and peak plasma viral load after challenge, consistent with the role of NtAb to protect against infection. T-cell responses as measured by HIV-specific interferon-gamma and TNF-alpha secreting cells in flow cytometric analysis were weak or undetectable before challenge. Together, these results indicate that protective immunity against mucosal infection with a CCR5-using primate lentivirus can be elicited by systemic prime-boost immunization and that boosting with protein immunogens appears to be superior than DNA or viral vectors in recombinant vaccinia virus or DNA primed animals in the generation of antigen-specific antibody responses.

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。 已显示异源性“初免-加强”免疫引发针对多种灵长类慢病毒（包括SIVmne、SHIVIIIB和SHIV89.6P）的保护性免疫。然而，比较不同初免-加强组合的保护功效的研究相对较少。该项目的目标是检查“初免-加强”免疫策略，以确定诱导抗体和CD 8 + T细胞介导的针对灵长类慢病毒的免疫应答的组合。 在本研究的前两个阶段中，我们比较了重组牛痘病毒或DNA疫苗的初免，然后是DNA，蛋白质或甲病毒加强，以保护免受粘膜攻击的能力与CCR 5-使用SHIVSF 162 P4。用表达HIV-1 SF 162全长env和SIVmac 239 gag/pol的重组牛痘病毒（组1-3）或表达相同抗原的DNA质粒（组5-7）引发24只猪尾猕猴。休息一段时间后，每组6只动物加强两次组1和5，表达在PBS中配制的密码子优化的SF 162 env gp 140或SIVmac 239 gag-pol的DNA质粒;组2和6，在MF 59中配制的蛋白免疫原SIVmac 239 Gag-Pol颗粒和SF 162 Env gp 140蛋白;或表达相同抗原的重组病毒载体（第3组为α病毒复制子，第7组为牛痘病毒重组体）。对照动物接受亲本牛痘病毒用于初免，空载体或佐剂仅用于加强。在最后一次免疫后，所有实验组中的动物产生SIV和HIV特异性抗体应答。与其他实验组中的动物相比，用蛋白质加强的动物（组2和6）具有显著更高的SIV特异性和HIV-1特异性gp 120抗体滴度，包括假型病毒测定中的同源中和滴度（p lt 0.001）。 最后一次免疫后四周，通过直肠内接种，用1，800 50%组织培养感染剂量的SHIVSF 162 P4攻击所有动物。猪尾猕猴中的SHIVSF 162 P4感染是稳健的，如gt 10^7拷贝/ml的平均血浆病毒峰值和gt 1/3动物中的持续病毒血症所示。在所有免疫组中均观察到平均血浆病毒载量的显著降低（第2组和第6组与对照组相比p lt 0.01;所有其他组p lt 0.05）。我们还观察到攻毒当天的同源中和抗体（NtAb）滴度与攻毒后血浆病毒载量峰值之间存在显著的负相关性（斯皮尔曼r =-0.819，p lt 0.0001），这与NtAb保护免受感染的作用一致。在激发前，通过流式细胞术分析中的HIV特异性干扰素-γ和TNF-α分泌细胞测量的T细胞应答较弱或不可检测。 总之，这些结果表明，针对使用CCR 5的灵长类慢病毒的粘膜感染的保护性免疫可以通过全身性引发-加强免疫来引发，并且在重组牛痘病毒或DNA引发的动物中，用蛋白质免疫原加强似乎上级DNA或病毒载体产生抗原特异性抗体应答。