PATHOGENESIS OF AN X4-TROPIC VARIANT OF SIVMAC239

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。 我们已经在体外获得了一种SIVmac239的变体，称为SIVmac239-ST1，它显示出对X4的高效利用。我们用这种新病毒感染了四只雄性恒河猴，以评估其共受体的变化对体内病毒复制和宿主控制的影响。在这个方案中，我们用SIVmac239-ST1的1×103 TCID50静脉接种了4只印度猕猴。采集血液样本进行流式细胞仪分析，并监测血浆病毒载量、体液免疫反应和动物的整体健康(CBC和化学)。同时采集脑脊液进行病毒载量分析。淋巴和肠道活检用于病毒的原位定位以及白细胞的分离和流式细胞术分析。进行了身体检查，以监测动物的整体健康状况。所有四只动物都被感染，BDNA测量的病毒载量峰值在6.5到7.2个对数拷贝/毫升之间。感染的设定点在3.5到6.5个对数拷贝/毫升之间。一只动物在攻击后368天发病并被人道安乐死。其余3只动物分别于攻击后314天(n=2)和371 d(n=1)被人道安乐死。在所有四只动物感染后，CCR5显著降低，其中一只动物的淋巴组织中CCR5显著降低。感染后，两只动物肠道中的CXCR4也减少(另外两只没有检测)。感染后，所有四只动物的肠道中的CD4都下降了。在一只显示出艾滋病迹象的动物的全血中，CD4细胞稳步下降。

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. We have derived, in vitro, a variant of SIVmac239, termed SIVmac239-ST1, that exhibits high efficiency use of X4. We used this new virus to infect four male rhesus macaques to assess the effects of its altered co-receptor usage on in vivo viral replication and host control. In this protocol we intravenously inoculated four Rhesus macaques of Indian origin with 1X103 TCID50 of SIVmac239-ST1. Blood samples were collected for flow cytometry analysis as well as to monitor plasma viral load, humoral immune responses and the overall health of the animals (CBC and Chemistry). CSF was also collected for viral load analysis. Lymph node and intestinal biopsies were used for localization of the virus in situ as well as isolation of leukocytes and flow cytometry analysis. Physical exams were performed to monitor the overall health of the animals. All four animals became infected and had peak viral loads between 6.5 and 7.2 log copies/ml measured by bDNA. The set point of infection ranged between 3.5 and 6.5 log copies/ml. One animal became sick and was humanely euthanized 368 days post-challenge. The other three animals were humanely euthanized on 314 days (n=2) and 371 days (n=1) post-challenge. CCR5 decreased dramatically after infection in all four animals and in the lymph node of one animal. CXCR4 also decreased in the gut of two animals after infection (the other two were not tested). CD4 decreased in the gut of all four animals after infection. CD4 cells steadily declined in the whole blood of the one animal that showed signs of AIDS.