脑膜、脉络丛淋巴细胞动态分布是中枢和外周免疫对话的关键，IFN-γ是其中的关键调节分子。以自闭症为代表的一类社交障碍相关的神经精神疾病常伴随脑膜及脉络丛淋巴细胞亚群分布变化及IFN-γ分泌异常。OT(催产素）通过特定神经环路及内分泌、旁分泌途径调节社交行为和免疫反应。我们前期研究结果发现不同行为范式诱导的社交障碍常伴随脑膜及脉络丛IFN-γ水平的改变、OT水平波动及下丘脑PVN区小胶质细胞活化，但不清楚社交线索诱导的OT水平改变是否影响脑膜及脉络丛淋巴细胞亚群分布及IFN-γ分泌，是否通过此途径发挥神经-免疫协同调节作用。本研究利用化学遗传技术操纵下丘脑PVN区OT神经元，利用质谱流式技术检测脑膜及脉络丛淋巴细胞亚群分布，探索在不同社交行为范式下，OT神经元状态对脑膜及脉络丛淋巴细胞亚群分布的影响，结合IFN-γ基因敲除，研究IFN-γ的调节作用，揭示OT在社交响应和免疫调节中的协同机制。

Dynamic distribution of lymphocyte in meninges and choroid plexus play important roles in cross-talk between central nerves system and immunologic system. In this process, interferon -γ (IFN-γ) serve as the key molecule to refine the regulation. Neuropsychiatric disease characterized by the social defeat, such as autism frequently accompanied the aberrant distribution of lymphocyte in meninges and choroid plexus and abnormal secretion of IFN-γ. Previous study indicated oxytocin play the synergistic regulation on social behavior and immunoreaction through the specific neural circuit, endocrine and paracrine pathway. Our preliminary study indicated that social defeat accompanied the changes of IFN-γ in meninges and choroid plexus and microglial activation in PVN of hypothalamus. Simultaneously, oxytocin fluctuation is obvious in different social paradigm. Nevertheless, it is still unknown whether the fluctuation of oxytocin induced by social cues affect the distribution of lymphocyte in meninges and choroid plexus and generation of IFN-γ. Whether oxytocin synergistically regulated the social behavior and immunoreaction through IFN-γ signals originated from the meninges and choroid plexus. In this proposes, DREADDs (Designer Receptors Exclusively Activated by Designer Drugs) technology was used to control the oxytocinergic neurons in PVN. Cytometry by time of flight technology was used to identify the subset of lymphocyte in meninges and choroid plexus. The aim of this study focused on the effects of oxytocin on distribution of lymphocyte in meninges and choroid plexus under the different social paradigm. Furthermore, IFN-γ-KO mice were used to explore the roles of IFN-γ signals in immunoregulation and social defeat. This study will present the theoretical foundation and therapeutic target through immunotherapy on mental disorders.