Gendelman H E, Genis P, Jett M, Zhai Q H, Nottet H S
Department of Medicine, University of Nebraska Medical Center, Omaha 68198.
Adv Neuroimmunol. 1994;4(3):189-93. doi: 10.1016/s0960-5428(06)80256-1.
The pathological hallmark of HIV infection in brain is productive viral replication in cells of mononuclear phagocyte lineage including brain macrophages, microglia and multinucleated giant cells (Koenig et al., 1986; Wiley et al., 1986; Gabuzda et al., 1986; Stoler et al., 1986). These cells secrete viral and cell encoded neurotoxins that lead to neuronal injury, glial proliferation and myelin pallor during advancing disease (Genis et al., 1992; Giulian et al., 1990, 1993; Pulliam et al., 1991). The apparent paradox between the distribution and numbers of virus infected cells and brain tissue pathology support indirect mechanisms for CNS damage (Epstein, 1993; Geleziunas et al., 1992; Merrill and Chen, 1992; Michaels et al., 1988; Price et al., 1988). First, brain macrophages and microglia can produce neurotoxins by secretion of viral proteins (for example, gp120) (Dawson et al., 1991; Merrill et al., 1989; Lipton et al., 1990; Lipton, 1993). Second, HIV primes macrophages for immune activation to produce neurotoxins including: cytokines (TNF alpha and IL-1 beta), eicosanoids: quinolinate and nitric oxide (NO). Chronic immune stimulation mediated by opportunistic infections and chronic interferon gamma (IFN gamma) production (in and outside the CNS) continues the process of macrophage activation leading to progressive neural injury. The hyperresponsiveness of HIV-infected macrophages to activation results in production of cellular factors that activate uninfected macrophages. This suggests that HIV-infected macrophages are both perpetrators and amplifiers for neurotoxic activities.
HIV感染脑部的病理标志是在单核吞噬细胞系细胞中进行病毒的有效复制,这些细胞包括脑巨噬细胞、小胶质细胞和多核巨细胞(凯尼格等人,1986年;威利等人,1986年;加布兹达等人,1986年;斯托勒等人,1986年)。在病情进展过程中,这些细胞分泌病毒和细胞编码的神经毒素,导致神经元损伤、胶质细胞增殖和髓鞘苍白(吉尼斯等人,1992年;朱利安等人,1990年、1993年;普利厄姆等人,1991年)。病毒感染细胞的分布和数量与脑组织病理学之间明显的矛盾支持了中枢神经系统损伤的间接机制(爱泼斯坦,1993年;盖莱齐纳斯等人,1992年;梅里尔和陈,1992年;迈克尔斯等人,1988年;普赖斯等人,1988年)。首先,脑巨噬细胞和小胶质细胞可通过分泌病毒蛋白(例如,gp120)产生神经毒素(道森等人,1991年;梅里尔等人,1989年;利普顿等人,1990年;利普顿,1993年)。其次,HIV使巨噬细胞准备好进行免疫激活,以产生神经毒素,包括:细胞因子(肿瘤坏死因子α和白细胞介素-1β)、类花生酸、喹啉酸和一氧化氮(NO)。由机会性感染和慢性干扰素γ(IFNγ)产生(在中枢神经系统内外)介导的慢性免疫刺激持续巨噬细胞激活过程,导致进行性神经损伤。HIV感染的巨噬细胞对激活的高反应性导致产生激活未感染巨噬细胞的细胞因子。这表明,HIV感染的巨噬细胞既是神经毒性活动的肇事者,也是放大器。