Evaluating the role of IL-17A as an orchestrator of peripheral-central cross talk in depressive symptoms

总结用简单的术语描述研究，以便向普通观众宣传。这将是公开的，申请人有责任确保内容适合出版。不超过，4000个字符，包括空格和回车。大约30-40%的免疫介导的炎症性疾病（IMID）患者，如银屑病，经历抑郁症。这些对临床结果、生活质量和治疗依从性产生负面影响。越来越多的证据表明，外周炎症可能有助于抑郁症的起源。特别是，a）刺激外周炎症导致缓解-复发性抑郁症状B）与这种抑郁相关的异常神经连接与外周炎症相关，c）靶向特定外周炎症组分（细胞因子）的生物疗法改善抑郁症状。在这种情况下，IL-23/IL-17细胞因子轴是其病理学的中心，如成功应用该途径的抑制剂所证明的。此外，这个轴最近也被牵连在抑郁症的神经生物学在临床前和临床研究。我们的目标是揭示在IMID背景下抑郁症的机制，通过一项集中的免疫干预研究，在人类免疫疾病的特异性治疗性免疫拦截的背景下，使用最先进的成像技术检查脑回路。我们将检验抑郁症与IL-17 A介导的脑神经化学（谷氨酸）变化相关的假设。这反过来又会导致电生理学、功能和大脑区域结构的失调，这些区域对奖励和情绪至关重要。我们将使用高场强（7 T）磁共振波谱（MRS）以最大的精度测量大脑谷氨酸盐，并使用磁共振成像（MRI）将大脑功能和连接（MRI）的测量与神经放电（EEG）的测量融合在一起，这将使我们能够在时间和空间上以最佳分辨率水平测量大脑网络。这些成像和电生理终点将在基线和6周时在50名PsD患者中进行测量，这些患者以1：1的比例随机接受抗IL 17 A抗体（阿基诺单抗）或安慰剂治疗。我们预测，抗IL-17 A治疗将与脑谷氨酸表达减少和特定EEG/MRI测量的改善相关，我们认为这是抑郁症状的机械标志物。在这样做的过程中，我们希望更广泛地了解抑郁症的生物学理解，以期为这一重大社会优先事项产生迫切需要的新型药物靶点。

SummaryDescribe the research in simple terms in a way that could be publicised to a general audience. This will be made publicly available and Applicants are responsible for ensuring that the content is suitable for publication. No more than, 4000 characters including spaces and returns.Approximately 30-40% of patients with immune-mediated inflammatory diseases (IMIDs), such as Psoriatic disease, experience depression. These negatively affect clinical outcomes, quality of life and treatment adherence. There is accumulating evidence that peripheral inflammation may contribute to the origins of depression. In particular, a) stimulation of the peripheral inflammation results in remitting-relapsing depressive symptoms b) abnormal neural connectivity linked to this depression is correlated with peripheral inflammation and c) biologic therapies targeting specific peripheral inflammation components (cytokines) improve depressive symptoms.In this proposal, Psoriatic disease (PsD) will be our IMID exemplar. In this condition, the IL-23/IL-17 cytokine axis is central to its pathology, as proven by successful application of inhibitors to this pathway. Moreover, this axis has also recently been implicated in the neurobiology of depression in both preclinical and clinical studies. We aim to uncover the mechanisms that underlie depression in the context of IMIDs, delivered by a focused immune intervention study examining brain circuitry using state of the art imaging in the context of exquisitely specific therapeutic immune interception in human immune disease. We will test the hypotheses that depression is associated with changes in brain neurochemistry (glutamate) mediated by IL-17A. This in turn drives dysregulation in electrophysiology, function, and structure of brain regions central to reward and emotion. We will use high field strength (7T) magnetic resonance spectroscopy (MRS) to measure brain glutamate with the greatest available precision and magnetic resonance imaging (MRI) to fuse measures of brain function and connections (MRI) with measures of nerve firing (EEG) that will allow us to measure brain networks at optimal levels of resolution in time and space. These imaging and electrophysiological endpoints will be measured at baseline and 6 weeks in 50 PsD patients, randomised 1:1 to treatment with anti-IL17A antibody(secukinumab) or placebo. We predict that anti-IL17A treatment will be associated with reduced brain glutamate expression and amelioration of specific EEG/MRI measures which we consider mechanistic markers of depressive symptoms. In doing so we expect to inform the biological understanding of depression more generally with view to generating urgently needed novel drug targets for this major societal priority.