Cross-talk between microglia and neurons regulates HIV latency
Cross-talk between microglia and neurons regulates HIV latency
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DOI：
10.1371/journal.ppat.1008249
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发表时间：
2019-12-01
期刊：
影响因子：
6.7
通讯作者：
Karn, Jonathan
中科院分区：
文献类型：
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作者：
Alvarez-Carbonell, David;Ye, Fengchun;Karn, Jonathan
由于抗逆转录病毒治疗的改善，艾滋病毒患者的寿命延长，艾滋病毒相关神经认知障碍（HAND）的患病率正在上升。HAND与慢性炎症和小胶质细胞增生有关，并因滥用物质如甲基苯丙胺（METH）而加剧。使用神经元和小胶质细胞的共培养模型，我们证明了健康的神经元可以在短期内（24小时）抑制感染的小胶质细胞中的HIV转录。相比之下，受损的神经元会重新激活潜在的艾滋病毒表达。因此，在较长时间内（72小时），神经元失去抑制HIV表达的能力，导致神经损伤增强。这种潜伏期逆转和神经元变性的破坏性循环可由METH和炎症加剧。我们的研究结果支持了这一假设，即树突状细胞的简化和神经元损伤与HAND的结果，由神经元和小胶质细胞的串扰和外源性炎症stimulations.Despite有效的抗逆转录病毒治疗（ART），HIV相关的神经认知障碍（HAND）被发现在近三分之一的患者。使用细胞共培养系统，包括神经元和人类小胶质细胞感染艾滋病毒（h μ glia/HIV），我们调查的假设，艾滋病毒依赖性神经退行性变的结果从小胶质细胞内的潜伏期响应神经元损伤或炎症信号的HIV周期性出现。当表达HIV的克隆h μ胶质细胞/HIV群体（HC 69）或HIV感染的人原代和iPSC衍生的小胶质细胞与健康神经元短期（24小时）培养时，HIV沉默。使用诱导的多能干细胞（iPSC）衍生的GABA能皮质（iCort）和多巴胺能（iDopaNer）神经元而不是运动神经元（iMotorNer）神经元来重现HC 69细胞中潜伏期的神经元依赖性诱导。相比之下，受损的神经元诱导潜伏感染的小胶质细胞中的HIV表达。共培养48-72小时后，低水平的HIV表达似乎会损伤神经元，这进一步增强了HIV表达。有一个显着的减少，在完整的树突染色微管相关蛋白2（MAP 2）的神经元暴露于HIV表达的小胶质细胞，表明广泛的树突修剪。为了模拟甲基苯丙胺（METH）诱导的神经毒性，我们用nM水平的METH和次优水平的poly（I：C）处理细胞，poly（I：C）是一种TLR 3激动剂，其模拟在HIV感染患者中发现的循环细菌rRNA的作用。这种药物组合有效诱导HIV表达，METH效应由sigma 1受体（sigma 1 R）介导。在HC 69细胞与iCort神经元的共培养物中，METH和poly（I：C）的组合诱导HIV表达和树突状细胞损伤，超过单独使用任一试剂所见的水平。因此，我们的结果表明，健康神经元和小胶质细胞之间的串扰调节HIV表达，而HIV表达损害这种内在分子机制，导致小胶质细胞介导的神经毒性的过度和不受控制的刺激。
Author summary Now that HIV patients are living longer due to improved anti-retroviral therapy, the prevalence of HIV-associated neurocognitive disorders (HAND) is rising. HAND is linked to chronic inflammation and microgliosis and is exacerbated by substances of abuse such as methamphetamine (METH). Using co-culture models of neurons and microglia, we demonstrate that healthy neurons can suppress HIV transcription in infected microglia over a short-term (24 h). By contrast, damaged neurons reactivate latent HIV expression. Thus, over a longer term (72 h), neurons lose the ability to suppress HIV expression, resulting in enhanced neural injury. This damaging cycle of latency reversal and neuronal degeneration can be exacerbated by METH and inflammation. Our results support the hypothesis that the dendritic simplification and neuronal injury associated with HAND results from viral reactivation induced by neuronal and microglial cross-talk and exogenous inflammatory stimuli.Despite effective antiretroviral therapy (ART), HIV-associated neurocognitive disorders (HAND) are found in nearly one-third of patients. Using a cellular co-culture system including neurons and human microglia infected with HIV (h mu glia/HIV), we investigated the hypothesis that HIV-dependent neurological degeneration results from the periodic emergence of HIV from latency within microglial cells in response to neuronal damage or inflammatory signals. When a clonal h mu glia/HIV population (HC69) expressing HIV, or HIV infected human primary and iPSC-derived microglial cells, were cultured for a short-term (24 h) with healthy neurons, HIV was silenced. The neuron-dependent induction of latency in HC69 cells was recapitulated using induced pluripotent stem cell (iPSC)-derived GABAergic cortical (iCort) and dopaminergic (iDopaNer), but not motor (iMotorNer), neurons. By contrast, damaged neurons induce HIV expression in latently infected microglial cells. After 48-72 h co-culture, low levels of HIV expression appear to damage neurons, which further enhances HIV expression. There was a marked reduction in intact dendrites staining for microtubule associated protein 2 (MAP2) in the neurons exposed to HIV-expressing microglial cells, indicating extensive dendritic pruning. To model neurotoxicity induced by methamphetamine (METH), we treated cells with nM levels of METH and suboptimal levels of poly (I:C), a TLR3 agonist that mimics the effects of the circulating bacterial rRNA found in HIV infected patients. This combination of agents potently induced HIV expression, with the METH effect mediated by the sigma 1 receptor (sigma 1R). In co-cultures of HC69 cells with iCort neurons, the combination of METH and poly(I:C) induced HIV expression and dendritic damage beyond levels seen using either agent alone, Thus, our results demonstrate that the cross-talk between healthy neurons and microglia modulates HIV expression, while HIV expression impairs this intrinsic molecular mechanism resulting in the excessive and uncontrolled stimulation of microglia-mediated neurotoxicity.