Vaccine immunogenicity and efficacy in the rhesus macaque/SHIV model

项目2试图在恒河猴(RM)/SIV模型中测试病毒体体疫苗的免疫原性和有效性。 Mymetics已经改进了用空的流感病毒样颗粒构建的病毒体疫苗，这些颗粒显示出 表面长的HIV gp41多肽(病毒体-P1)或重组截短的HIV gp41(病毒体-P1) Rgp41)。早些时候，中国的RMS被给予两个肌肉内(IM)素数，然后是两个鼻内(IN)增强 100%预防持续系统感染，小剂量阴道内注射后未出现SIV GAG血清转换 希夫挑战。印度RMS的一项跟踪研究显示，只要SHIV剂量是 ~7x104倍的HIV疫苗接种在人类从男性到女性的HIV传播中，但当接种SHIV疫苗时 大了~105倍，就失去了保护。在这些NHP研究中，未加辅料的液体制剂 使用病毒体-P1+病毒体-rgp41的组合。为了提高免疫原性，Mymetics将 Toll样受体(TLR)7/8佐剂3M-052直接进入病毒体膜并形成固体冷链 可以无针注射的独立疫苗配方。粉状病毒体形式可以是 作为IN喷雾剂、舌下(SL)片剂或包装成口服胶囊(PO)。我们的总体假设是 冷链非依赖的、无针佐剂的固体病毒体形式明显更具免疫原性 与RMS中早期的液体形式相比，在粘膜预充/粘膜后将诱导更高的粘膜液抗体水平 通过不同的路线进行助推。Mymetics已经在IN和SL形式的小动物身上进行了试点试验； 在RMS中，需要优化口服胶囊的疫苗递送。项目2的具体目标是： 1.通过肠溶胶囊优化疫苗向回肠的输送；a)监测胶囊的通过 通过扫描含有99mTc或64Cu；b)将荧光标记粘贴到病毒体体疫苗上，以在 近红外光谱。在尸检时收集的组织将用荧光显微镜进行测试。 2.通过启动/增强试验测试不同途径的新型佐剂病毒小体的免疫原性 接近。我们将通过IN、SL和PO途径测试它们的相对免疫原性；将通过 不同的粘膜途径，一种新颖的方法。对照组将用可溶性病毒体疫苗免疫IM。 3.测试冷链非依赖、无针、佐剂病毒体疫苗对反复发作的效力 低剂量直肠内(IR)分支B-SHIV(SHIV-B)挑战。免疫原性最强的粘膜原液/粘膜 Boost方案(见目标2)将用于12个RMS组的免疫；对照组(n=12)将接受空的免疫 病毒小体。所有RMS将接受每周约10次的低剂量IR挑战，使用第2级R5分支B SHIVSF162P3。 4.测试抵抗多个Shiv-B挑战的RM是否会受到跨分支挑战的保护 第2层R5分支C Shiv。受保护的均方根将用于确定保护的相关性。 这些创新对发展中国家非常重要，我们的新型疫苗将是那里的一大优势 以抗击艾滋病的流行。

Project 2 seeks to test virosomal vaccine immunogenicity and efficacy in the rhesus macaque (RM)/SHIV model. Mymetics has improved virosomal vaccines built from empty influenza virus-like particles that display an elongated HIV gp41 peptide on their surface (virosome-P1) or recombinant truncated HIV gp41 (virosome- rgp41). Earlier, Chinese RMs given two intramuscular (IM) primes followed by two intranasal (IN) boosts were 100% protected from persistent systemic infection and did not seroconvert to SIV Gag after low-dose intravaginal SHIV challenges. A follow-up study in Indian RMs showed 78% to 87% protection as long as the SHIV dose was ~7x104 times the median HIV inoculum in human male-to-female HIV transmission, but when the SHIV inoculum was ~105x greater, protection was lost. In these NHP studies, unadjuvanted, liquid formulations of the combination of virosome-P1 + virosome-rgp41 were used. To improve immunogenicity, Mymetics embedded the toll-like receptor (TLR)7/8 adjuvant 3M-052 directly into virosome membranes and developed solid, cold-chain independent vaccine formulations that can be administered needle-free. The powdered virosome forms can be given as IN spray, sublingual (SL) tablets, or packaged into oral capsules (PO). Our overall hypothesis is that the cold-chain independent, needle-free adjuvanted solid virosome forms are significantly more immunogenic than their earlier liquid form in RMs and will induce higher mucosal fluid Ab levels after mucosal priming/mucosal boosting via different routes. Mymetics has performed pilot tests in small animals with the IN and SL forms; vaccine delivery via oral capsules needs to be optimized in RMs. The Specific Aims for Project 2 are to: 1. Optimize vaccine delivery to the ileum via enteric-coated capsules; a) monitor passage of capsules containing 99mTc or 64Cu by scans; b) attach fluorescent labels to the virosomal vaccines for detection in the near-infrared spectrum. Tissues collected at necropsy will be tested by fluorescent microscopy. 2. Test the immunogenicity of different routes of the novel adjuvanted virosomes through a prime/boost approach. We will test their relative immunogenicity via IN, SL and PO routes; boosts will be given via a different mucosal route, a novel approach. Controls will be immunized IM with the soluble virosomal vaccine. 3. Test the efficacy of the cold-chain independent, needle-free, adjuvanted virosomal vaccines against repeated low-dose intrarectal (IR) clade B SHIV (SHIV-B) challenges. The most immunogenic mucosal prime/mucosal boost regimen (see Aim 2) will be used to immunize a group of 12 RMs; control (n=12) will receive empty virosomes. All RMs will undergo ~10 weekly low-dose IR challenges with the tier 2, R5 clade B SHIVSF162P3. 4. Test whether RMs that resisted multiple SHIV-B challenges will be protected against cross-clade challenge with the tier 2 R5 clade C SHIV. Protected RMs will be used to determine correlates of protection. These innovations are highly significant for the developing world, where our novel vaccine will be a major plus to combat the AIDS epidemic.