RHESUS MACAQUE MODEL FOR GBV-C AND SIV CO-INFECTION

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 本实验旨在建立GBV-C和SIV混合感染恒河猴模型，以研究GBV-C和HIV的相互作用以及GBV-C延缓艾滋病进展的机制。本研究选用5只中国原产恒河猴(CH Rh)。每只动物通过静脉途径接种10毫升含有GBV-C的人类捐献者的血液。然而，猴子没有感染GBV-C，但研究了SIVmac239接种后T细胞的转化。在SIV接种前、感染后2周和26周静脉注射BrdU 60 mg/kg/只。在注射BrdU前、注射BrdU后24小时、48小时和72小时，用多参数流式细胞仪检测BrdU、Ki67抗原和表面T细胞亚群表型标志物，前瞻性地检测外周血中T淋巴细胞。在第2周，PVL的平均峰值为107拷贝/毫升。1只动物的病毒载量在病毒血症高峰后第26周下降到300拷贝/毫升(LTNP病毒控制组)。其余动物PVL的设定值为106拷贝/毫升(进展值)。对控制组和进展组T细胞动态的比较表明，控制组的CD4+T细胞比例与其他动物相似，但它有75%的记忆CD4+T细胞(CD4+CD95+)，其他动物的平均比例为58.8%(范围在46%~67%之间)。所有动物都有相似水平的效应记忆(CD28-CD95+)CD4+T细胞(平均6.5%)，但控制组在感染前有相对较高的中央记忆(CD28+CD95+)CD4+T细胞(控制组与进展组：67.8%对51.1%)。记忆性CD4+T细胞从58.8%迅速下降到30.6%(P<0.01)。至36%(第26周P.I.)在进步者中，控制者的比例从75%到46.8%到60.8%。中枢记忆细胞进展者为51%~24.6%~36.5%，控制者为68%~41%~60%。记忆性CD4+CCR5+T细胞在第2周也略有下降。在所有动物中，并维持在进展期较低的水平，但在第26周P.I.控制组增加到1.5倍。在第2周和第26周，记忆性CD4+T细胞的增殖能力增加了2~5倍。CD8+T细胞中Ki67+BrdU+的比例在感染后2周增加了15倍和20倍，在感染后26周继续增加7倍和10倍，这些增加的细胞大多是记忆性CD8+T细胞。与感染前相比，急性期动物的NK+增殖显著增加，但病毒载量最低的动物NK+增殖最低。综上所述，记忆性CD4+T细胞的恢复，尤其是中央记忆性CD4+T细胞的恢复与病毒抑制相关。在SIVmac感染过程中，CD8+T细胞大量增殖。因果关系还需要进一步研究。

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. The aim of this pilot study is to establish a GBV-C and SIV coinfection rhesus macaque model for studying the GBV-C and HIV interactions and mechanisms of the potential benefit of GBV-C to slow progression of AIDS. Five Chinese-origin rhesus macaques (Ch Rh) were used in this study. Each animal was inoculated by intravenous route with 10 ml of blood from a human donor containing GBV-C. However, monkeys were not infected with GBV-C, but T cell turnover was studied after SIVmac239 inoculation. BrdU was injected intravenously with 60 mg/kg per animal before SIV inoculation, at week 2 and week 26 post infection. T Lymphocytes were assessed prospectively by multiparameter flow cytometric analysis with intracellular staining for BrdU and Ki67 antigen along with surface T cell subset phenotyping markers in peripheral blood before BrdU injection, 24hrs, 48hrs and 72hrs after BrdU injection. The average peak PVL was 107 copies/ml at week 2. One animal had a viral load that decreased to 300 copies/ml at week 26 after the peak viremia (LTNP virus controller). The set points of PVL in the other animals were 106 copies/ml (progressors). Comparison of the dynamics of T cells between the controller and progressors showed that while the controller had similar percentage of CD4+ T cells as the other animals, it had 75% of memory CD4+ T cells (CD4+CD95+), the others had an average 58.8% (ranged from 46% ~ 67%). All animals had similar levels of effector memory (CD28-CD95+) CD4+ T cells (average of 6.5%), but the controller had relatively high central memory (CD28+CD95+) CD4+ T cells before infection (controller vs progressor: 67.8% vs 51.1%). Memory CD4+ T cells rapidly decreased from 58.8% to 30.6% (week 2 p.i.) to 36% (week 26 p.i.) in progressors, and from 75% to 46.8% to 60.8% of the controller. The central memory cells from 51% to 24.6% to 36.5% of progressors and 68% to 41% to 60% of controller. Memory CD4+ CCR5+T cells also slightly decreased at week 2 p.i. in all animals, and maintained the low levels in progressors but increased to 1.5 fold higher in the controller at week 26 p.i.. Proliferation of memory CD4+ T cells were two- to five-fold increase at week 2 and week 26 p.i.. The portion of Ki67+BrdU+ of CD8+ T cells increased 15-fold in progressors and 20-fold in the controller at week 2 p.i, and continued to be 7-fold in progressors and 10-fold in the controller at week 26 after infection, most of these increased cells were memory CD8+ T cells. NK+ proliferation significantly increased during the acute phase compared to baseline before infection, however, the animal that had the lowest viral load had lowest NK+ proliferation. In conclusion, memory CD4+ T cell restoration, especially central memory CD4+ T cells restoration, correlated with virus suppression. Massive proliferation of CD8+ T cells were induced during SIVmac infection. A cause and effect relationship will require further study.