Polygenic Risk for Alcohol Use Disorder Affects Cellular Responses to Ethanol Exposure in a Human Microglial Cell Model II

Polygenic risk scores (PRS) assess genetic susceptibility to Alcohol Use Disorder (AUD), yet their molecular implications remain underexplored. Neuroimmune interactions, particularly in microglia, are recognized as significant contributors to AUD pathophysiology. We investigated the interplay between AUD PRS and ethanol in human microglia derived from iPSCs from individuals with high-or low-PRS (HPRS or LPRS) of AUD. Ethanol exposure induced elevated CD68 expression and morphological changes in microglia, with differential responses between HPRS and LPRS microglial cells. Transcriptomic analysis revealed expression differences in MHCII complex and phagocytosis-related genes following ethanol exposure; HPRS microglial cells displayed enhanced phagocytosis and increased CLEC7Aexpression, unlike LPRS microglial cells. Synapse numbers in co-cultures of induced neurons with microglia after alcohol exposure were lower in HRPS co-cultures, suggesting possible excess synapse pruning. This study provides insights into the intricate relationship between AUD PRS, ethanol, and microglial function, potentially influencing neuronal functions in developing AUD. Overall design: Cultures were prepared of iPS cells from multiple iPSC lines prepared from subjects with AUD and high polygenic risk (HPRS) and unaffected with low polygenic risk (LPRS). Total cellular RNA was prepared for quality assurance assays.多基因风险评分（Polygenic Risk Scores，PRS）可用于评估个体罹患酒精使用障碍（Alcohol Use Disorder，AUD）的遗传易感性，但其分子层面的潜在调控机制仍未得到充分探索。神经免疫相互作用，尤其是小胶质细胞（microglia）的相关功能，已被证实是酒精使用障碍病理生理过程中的重要影响因素。本研究针对携带高、低酒精使用障碍多基因风险评分（High Polygenic Risk Score，HPRS；Low Polygenic Risk Score，LPRS）的个体诱导多能干细胞（induced pluripotent stem cells，iPSCs）分化而来的小胶质细胞，探究了酒精使用障碍多基因风险评分与乙醇之间的相互作用。乙醇暴露可诱导小胶质细胞的CD68表达上调并引发形态学改变，且HPRS组与LPRS组的小胶质细胞呈现出截然不同的应答模式。转录组学分析结果显示，乙醇暴露后，主要组织相容性复合体II（Major Histocompatibility Complex II，MHCII）复合物以及与吞噬作用相关的基因表达存在显著差异；与LPRS组小胶质细胞相比，HPRS组小胶质细胞表现出更强的吞噬活性以及CLEC7A基因表达的上调。酒精暴露后，诱导神经元与小胶质细胞的共培养体系中，HPRS组的突触数量显著降低，这提示可能存在过度的突触修剪现象。本研究揭示了酒精使用障碍多基因风险评分、乙醇与小胶质细胞功能之间的复杂关联，该关联或可通过影响神经元功能参与酒精使用障碍的发生发展。总体实验设计：本研究从携带高酒精使用障碍多基因风险评分的酒精使用障碍患者，以及携带低多基因风险评分的健康对照个体的诱导多能干细胞系中制备细胞培养体系；随后提取总细胞RNA用于质控分析实验。