Neuron-macrophage interactions in models of chemotherapy-induced peripheral neuropathy

摘要/摘要： 化疗引起的周围神经病(CIPN)在美国影响着300多万人，但没有有效 治疗。CIPN主要影响伤害性(痛觉)神经末梢，通常表现为 患者的慢性衰弱疼痛。化疗引起的炎症与肺癌的发病密切相关 以及持续性神经病理性疼痛。我们建议研究巨噬细胞之间的外周相互作用， 最丰富的免疫细胞类型存在于皮肤和CIPN中的伤害性神经末梢。分子图谱 巨噬细胞根据其细胞外环境不断变化，使它们能够从 驻留到激活状态。虽然巨噬细胞的促炎和抗炎活性已经被广泛地 经过研究，最近的研究揭示了过渡过程中的许多中间形式。它们如何关联到 神经的病理演变仍然知之甚少，我们建议用两种方法来填补这一空白。 互补系统，果蝇和小鼠CIPN模型。我们将检验这样一个假设，即调制 巨噬细胞激活可预防CIPN的外周感觉神经元超敏反应。在我们的 前期工作，我们建立了果蝇模型来研究体内神经元-巨噬细胞的相互作用，并发现 巨噬细胞以时间依赖的方式激活并转变为不同的中间形式， 与伤害性神经元表型相对应。利用使用Depth的单细胞定量方法 学习细胞原位检测，我们发现激活的巨噬细胞的扩张高峰先于形态 神经元变性，选定的促炎和抗炎基因显著增加。我们进一步发现 后期抗炎巨噬细胞显著减少，表明免疫状态改变 介于病理中期和晚期之间。寻找可以调节巨噬细胞的基因 激活以促进神经元健康，同时不干扰它们在宿主防御中的作用，我们发现 中脑星形胶质细胞源性神经营养因子，作为预防CIPN的潜在基因靶点。 MANF是一种强大的免疫活性调节剂，它的过度表达减少了促炎途径 并促进抗炎途径的激活。作为支持，我们的初步结果表明 增强MANF预防果蝇和小鼠CIPN模型中的神经元表型，与我们的研究一致 假设。我们建议表征化疗诱导的巨噬细胞图谱，并研究MANF如何 调节巨噬细胞预防果蝇体内神经元毒性及小鼠神经元-巨噬细胞联合作用 培养CIPN模式。我们的建议有很大的潜力有助于有效的抗炎治疗 促进CIPN中的神经元健康。

Summary/Abstract: Chemotherapy-induced peripheral neuropathy (CIPN) affects over 3 million people in the US without effective treatment. CIPN predominantly affects nociceptive (pain-sensing) nerve terminals, and often manifests as chronic debilitating pain in patients. Chemotherapy-induced inflammation strongly correlates with the onset of and persistent neuropathic pain. We propose to investigate peripheral interactions between macrophages, the most abundant immune cell type residing in skin, and nociceptive nerve terminals in CIPN. Molecular profiles of macrophages change continuously depending on their extracellular environment, allowing them to transition from resident to activated states. While pro- and anti-inflammatory activation of macrophages has been extensively studied, recent studies revealed many intermediate forms during the transition. How these are linked to pathological progression of nerves is still poorly understood, and we propose to fill this gap by using two complementary systems, Drosophila and mouse CIPN models. We will test the hypothesis that modulating macrophage activation could prevent peripheral sensory neuron hypersensitivity in CIPN. In our preliminary work, we established a Drosophila model to study neuron-macrophage interaction in vivo and found that macrophages activate and transition into different intermediate forms in a time-dependent manner that corresponds to nociceptive neuron phenotypes. Leveraging a single-cell quantitative approach using deep learning cell detection in situ, we found that expansion of activated macrophages peaks preceding morphological degeneration of neurons with a robust increase in selected pro- and anti-inflammatory genes. We further found a significant reduction in anti-inflammatory macrophages at a later stage, indicating an immune state switch between intermediate and late pathological stages. In search of genes that could modulate macrophage activation to promote neuronal health while not interfering with their roles in host defense, we identified mesencephalic astrocyte-derived neurotrophic factor, MANF, as a potential gene target for CIPN prevention. MANF is a potent regulator of immune activity, and its overexpression reduces the pro-inflammatory pathway and promotes activation of the anti-inflammatory pathway. In support, our preliminary results demonstrate that augmenting MANF prevents neuron phenotypes in Drosophila and mouse CIPN models, consistent with our hypothesis. We propose to characterize chemotherapy-induced macrophage profiles and investigate how MANF modulates macrophages to prevent neuronal toxicity in Drosophila in vivo and mouse neuron-macrophage co- culture CIPN models. Our proposal has a high potential to contribute to effective anti-inflammatory treatment for promoting neuronal health in CIPN.