VIRAL AND CELLULAR DETERMINANTS OF HIV DEMENTIA

仍然没有解决的是为什么艾滋病痴呆通常不会 发展到出现坦率的免疫抑制，如果确实如 有证据表明，HIV-1在感染早期就进入了大脑。虽然 被感染的单核细胞进入大脑的运输经常是 预示着艾滋病毒进入中枢神经系统(CNS)的模式， 很少有研究研究循环中单核细胞感染艾滋病毒的情况 神经疾病的背景，包括艾滋病和痴呆症。同样， 尽管单核细胞，可能包括感染了艾滋病毒的人 一种，从骨髓进入血液，对艾滋病毒宿主知之甚少 这种组织中的细胞相互作用。这些细胞之间的相互关系 血液、脑和骨髓--与艾滋病毒感染有关 而艾滋病痴呆症的发展，是这项提案的一大重点。 这些互动的细胞和病毒方面都将是 调查过了。痴呆症患者和非痴呆症患者的单核细胞 后续纵向检查CD16细胞表面 增殖细胞核抗原(增殖细胞核抗原)表达。这个 克隆试验中的增殖能力和环状形式的存在 HIV-1DNA。患者的脑和骨髓组织 将对痴呆进行检查以确定是否存在增殖细胞核抗原阳性的巨噬细胞 以及环状艾滋病毒DNA的存在。虽然艾滋病的细胞决定因素 痴呆症可能主要与发生在户外的事件有关 中枢神经系统，在进入大脑之前，很可能是许多病毒 这种疾病的决定因素与进入后事件有关。因此， 痴呆症病毒决定因素的识别，互补 来自脑和血单核细胞的HIV病毒表型的研究 建议。这些病毒来自痴呆症患者和非痴呆症患者， 评估复制潜力、表达水平、 传播，诱导细胞因子和趋化因子产生的能力，以及 在体外杀死人类神经元。这些病毒的表型将是 与从同一患者的T细胞中恢复的数据进行比较。 将构建嵌合病毒来识别基因决定因素 与生物特性相关。定点突变将 被用来精确定位关键核苷酸和激活 感染的巨噬细胞的细胞内信号通路将被检测。 我们相信，对单核细胞贩运动力学的理解， 无论是感染的还是未感染的，都对发展至关重要 艾滋病毒神经系统疾病的成功治疗方式。

Still unresolved is the paradox of why AIDS dementia does not generally develop until the onset of frank immunosuppression, if, indeed, as the evidence indicates, HIV-1 enters the brain early in infection. Although the trafficking of infected monocytes into brain has frequently been heralded a the mode in HIV entry into the central nervous system (CNS), few studies have examined HIV infection of circulating monocytes within the context of neurological disease, including AIDS dementia. Similarly, in spite of the fact that monocytes, including, presumably, HIV-infected ones, enter the blood from the bone marrow, little is known about HIV-host cell interactions in this tissue. The interrelationships of these cellular compartments--blood, brain and bone marrow--with respect to HIV infection and the development of AIDS dementia, is a major focus of this proposal. Both cellular and viral aspects of these interactions will be investigated. Blood monocytes from patients with and without dementia, followed longitudinally, will be examined for CD16 cell surface expression, proliferating cell nuclear antigen (PCNA) expression. the ability to proliferate in clonal assays and the presence of circular forms of HIV-1 DNA. Brain and bone marrow tissues from patients with and without dementia will be examined for the presence of PCNA-positive macrophages and the presence of circular HIV DNA. While cellular determinants of AIDS dementia might be related primarily to events that take place outside of the CNS, prior to entry into brain, it is likely that many of the viral determinants of this disease related to post-entry events. Therefore, towards identification of viral determinants of dementia, complementary studies of HIV phenotype of viruses from brain and blood monocytes are proposed. These viruses, from patients with and without dementia, will be evaluated for replication potential, level of expression, ability to spread, ability to elicit cytokine and chemokine production, and ability to kill human neurons in vitro. The phenotypes of these viruses will be compared with those recovered from T-cells from the same patients. Chimeric viruses will be constructed to identify the genetic determinants associated with the biological properties. Site-directed mutagenesis will be used to pinpoint the critical nucleotide and activation of intracellular signaling pathways in infected macrophages will be examined. We believe an understanding of the dynamics of trafficking of monocytes, both infected and uninfected, is critical for the development of successful treatment modalities for HIV neurological disease.