Establishing a human cellular model of sex differences in the brain

众所周知，生理性别影响许多精神疾病的风险、发病年龄和/或严重程度。 和神经系统疾病。男性患帕金森病、自闭症、精神分裂症的几率更高 而女性患抑郁症、焦虑症、阿尔茨海默病和 多发性硬化此外，研究人员还观察到神经系统特性的性别差异 与神经发生、形态、基因表达、突触密度和连接性相关。这些差异 可能是由于不同的遗传学（XX与XY），激素的影响，和/或社会的复杂影响， 环境为了了解影响疾病和“正常”脑功能的具体因素， 这对于理解个体之间这种变异的细胞和分子基础至关重要。尽管有一些 令人信服的动物模型工作，分析人类性别差异的细胞和分子基础的研究 直到最近，大脑还很罕见部分原因是缺乏人类细胞模型 神经科学的一个系统，既与生物学相关，又受遗传控制。在此，我们建议 建立一个良好的控制，定义和可操作的人类干细胞模型，用于研究 遗传性别对神经精神疾病细胞机制的影响拟议的系统将提供 美国和其他人开发了一个简易的“插入式”系统，用于在基于干细胞的分析中加入性别差异成分。在 目的1，我们建议开发XX和XY干细胞系，它们在性染色体外是完全等基因的 补体性别差异不能明确归因于遗传学，只要常染色体基因组 也是发散的，并且由于没有常染色体等基因的雄性/雌性对的自然发生， 我们在此提出，设计人类干细胞系， 染色体组我们将使用我们手头的Klinefelter胚胎干细胞系（XXY）， 从Klinefelter成纤维细胞中开发新的iPSC。然后，我们将诱导这些线丢失单个X或Y 染色体，创建常染色体雄性和雌性干细胞系的亚克隆。在目标2中，我们将使用 在SA 1中开发的常染色体等基因干细胞系统，以鉴定与SA 1中的干细胞差异表达的基因和蛋白质。 受到性别遗传的影响为此，我们将我们的同基因XX和XY干细胞分别分化为 下丘脑和皮质的神经元、星形胶质细胞和小胶质细胞，并测定差异效应 XY和XX细胞在基因和蛋白调控上的差异。

It is well established that biological sex affects risk, age-of-onset, and/or severity of many psychiatric and neurological diseases. Men have a higher incidence of Parkinson's disease, autism, and schizophrenia while women show a higher incidence of major depressive disorder, anxiety disorder, Alzheimer's disease and multiple sclerosis. Additionally, researchers have observed sex differences across nervous system properties related to neurogenesis, morphology, gene expression, synapse density, and connectivity. These differences could be due to differential genetics (XX vs XY), hormonal influence, and/or the complex effects of social environment. To understand the specific factors influencing both disease and “normal” brain function, it is critical to understand the cell and molecular bases of this variation between individuals. In spite of some compelling animal model work, studies analyzing the cell and molecular bases of sex differences in the human brain have, until very recently, been rare. Part of the reason for this is the lack of a human cellular model system for neuroscience that is both biologically relevant and genetically controlled. Here, we propose to establish a well controlled, defined, and manipulatable human stem cell model for studying the impact of genetic sex on cellular mechanisms underlying neuropsychiatric diseases. The system proposed would provide us and others a facile “plug-in” system for adding a sex differences component to stem cell-based analyses. In Aim 1, we propose to develop XX and XY stem cell lines that are fully isogenic outside of the sex chromosome complement. Sex differences cannot be definitively attributed to genetics as long as the autosomal genome also is also divergent, and since there is no natural occurrence of an autosomally isogenic male/female pair, we propose here to engineer human stem cell lines that are genetically identical with the exception of the sex chromosome complement. We will use a Klinefelter embryonic stem cell line (XXY) that we have in hand and develop new iPSCs from Klinefelter fibroblasts. We then will induce these lines to lose either a single X or Y chromosome, creating subclones of autosomally male and female stem cell lines. In Aim 2, we will use the autosomally isogenic stem cell system developed in SA1 to identify genes and proteins that are differentially affected by genetic sex. For this aim we will differentiate our isogenic XX and XY stem cells individually into neurons of the hypothalamus and of the cortex, astrocytes, and microglia and assay differential effects between XY and XX cells on gene and protein regulation.