Chege Gerald K, Chapman Rosamund E, Keyser Alana T, Adams Craig H, Benn Kealan, van Diepen Michiel T, Douglass Nicola, Lambson Bronwen, Hermanus Tandile, Moore Penny L, Williamson Anna-Lise
Primate Unit and Delft Animal Centre, Centre and Platform Office, South African Medical Research Council, Parrow Valley, Cape Town 7505, South Africa.
Division of Medical Virology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town 7925, South Africa.
Viruses. 2025 Feb 17;17(2):277. doi: 10.3390/v17020277.
We previously reported on HIV vaccines that elicited autologous Tier 2 neutralizing antibodies (nAbs) in rabbits. In the current study, we sought to establish a proof of concept that HIV vaccines using identical designs elicit Tier 2 nAbs in arhesus macaque (RM) model. DNA and MVA vaccines expressing SIV Gag and HIV-1 Env antigens were constructed, and in vitro expression was confirmed. A soluble envelope protein (gp140 Env) was expressed from a stable HEK293 cell line and purified using lectin affinity and size exclusion chromatography. The expression and secretion of SIV Gag and HIV-1 Env by the DNA and MVA vaccines was verified in vitro. Five RMs were inoculated with two DNA, followed by two MVA, and finally with two gp140 Env vaccines at weeks 0, 4, 8, 12, 20 and 28. Vaccine-induced T cell immunity was measured by IFN-γ ELISpot while nAbs were evaluated against MW965 (Tier 1A), 6644 (Tier 1B), autologous ZM109.5A and a closely-related ZM109.B4 (Tier 2) pseudovirions. Vaccinated RMs were challenged intrarectally with simian-human immunodeficiency virus (SHIV), four weeks after the final vaccination, as was an unvaccinated control group ( = 4). Following vaccination, all the animals developed moderate IFN-γ ELISpot responses after the DNA vaccinations which were boosted by the MVA vaccine. After the gp140 Env boost, all animals developed nAbs with peak median titres at 762 (MW965) and 263 (ZM109.5A). The vaccinated animals became infected after a similar number of challenges to the unvaccinated controls, and the resultant number of viral copies in the blood and the lymphoid tissues were similar. However, the duration of detectable viraemia in the vaccinated animals (median: 2 weeks) was shorter than the controls (median: 8.5 weeks). These data show that the vaccines elicited robust cellular and functional humoral immune responses that resulted in a quicker control of viraemia.
我们之前报道了在兔子体内引发自体2级中和抗体(nAbs)的HIV疫苗。在当前研究中,我们试图确立一个概念验证,即使用相同设计的HIV疫苗在恒河猴(RM)模型中引发2级nAbs。构建了表达SIV Gag和HIV-1 Env抗原的DNA疫苗和MVA疫苗,并证实了其体外表达。从稳定的HEK293细胞系中表达可溶性包膜蛋白(gp140 Env),并使用凝集素亲和色谱和尺寸排阻色谱进行纯化。在体外验证了DNA疫苗和MVA疫苗对SIV Gag和HIV-1 Env的表达和分泌。5只恒河猴在第0、4、8、12、20和28周接种了两剂DNA疫苗,随后接种两剂MVA疫苗,最后接种两剂gp140 Env疫苗。通过IFN-γ ELISpot检测疫苗诱导的T细胞免疫,同时针对MW965(1A类)、6644(1B类)、自体ZM109.5A和密切相关的ZM109.B4(2级)假病毒评估nAbs。在最后一次接种后4周,对接种疫苗的恒河猴进行直肠内猴-人免疫缺陷病毒(SHIV)攻击,未接种疫苗的对照组(n = 4)也进行同样的操作。接种疫苗后,所有动物在接种DNA疫苗后均产生了中等程度的IFN-γ ELISpot反应,MVA疫苗增强了这种反应。在gp140 Env加强免疫后,所有动物均产生了nAbs,MW965的峰值中位滴度为762,ZM109.5A的峰值中位滴度为263。接种疫苗的动物在经历与未接种疫苗的对照组相似数量的攻击后被感染,血液和淋巴组织中产生的病毒拷贝数相似。然而,接种疫苗的动物中可检测到病毒血症的持续时间(中位值:2周)比对照组(中位值:8.5周)短。这些数据表明,这些疫苗引发了强大的细胞免疫和功能性体液免疫反应,从而更快地控制了病毒血症。