Development of a Novel Cell Based PDE10A Assay for Antipsychotic Drug Discovery

描述（申请人提供）：精神分裂症是一种慢性和破坏性的精神障碍，影响0.5- 0.8%的一般人口和超过200万人在美国。目前的治疗方案依赖于D2多巴胺受体靶向药物，这些药物对症状部分有效，并引起严重的副作用，导致高治疗中断和复发。磷酸二酯酶10A（PDE 10A）是治疗精神分裂症的一个新的药物靶点，有望开发出疗效更好、副作用更小的治疗药物。为了开发PDE 10A抑制剂，制药和生物技术公司在很大程度上依赖于无细胞酶测定和基于结构的药物设计。尽管PDE 10A的基于细胞的高通量筛选（HTS）分析将大大加速药物发现过程，并有助于发现具有不同作用机制和更好药理学性质的候选药物，但目前制药行业还没有商业产品。Codex Biosolutions拥有专有的cAMP生物传感器技术（ACTOne”），该技术已成功开发为基于细胞的检测方法，用于在1536孔HTS活动中筛选PDE 4抑制剂。在SBIR第一阶段的资助中，我们的目标是扩大最初的成功，建立一种基于PDE 10A细胞的检测方法，该方法将被业界用于开发精神分裂症疾病的创新疗法。我们将在位于马里兰州和新泽西的设施中进行所有研究，这些设施配备了完成该项目所需的所有必要资源。我们还将邀请来自西弗吉尼亚大学行为医学和精神病学系的Hanting Zhang博士，PDE研究专家，就该项目向我们提供咨询。我们为SBIR第一阶段提出以下四个具体目标。1.生成稳定的HEK 293-CNG-TSHR-PDE 10A细胞系。2.敲除PDE 4D和PDE 4 B基因以产生HEK 293-CNG-TSHR-PDE 10A-PDE 4D-/--PDE 4 B-/-细胞系（PDE 10A细胞系）。3.使PDE 10A细胞系适应384孔HTS格式。4.对化合物库进行高通量筛选，以评价鉴定已知PDE 10A抑制剂的试验性能。第一阶段的成功完成将为将相同的技术扩展到其他PDE亚型铺平道路，从而建立针对单个PDE变体的选择性基于细胞的测定方法库，这些方法将服务于针对广泛治疗领域的药物发现项目，包括CNS，炎症，代谢和癌症。

DESCRIPTION (provided by applicant): Schizophrenia is a chronic and devastating mental disorder that affects 0.5-0.8 percent general population and over 2 million people in the United States. The current treatment regimen depends on D2 dopamine receptor-targeted drugs that are partially effective on symptoms and cause severe side effects, leading to high treatment discontinuation and relapse. Phosphodiesterase 10A (PDE10A) is emerging as a novel drug target for schizophrenia that promises the development of therapeutics with improved efficacy and less side effects. To develop a pipeline of PDE10A inhibitors, pharmaceutical and biotech companies are depending heavily on cell-free enzymatic assays and structure-based drug design. Although cell-based high-throughput screening (HTS) assays for PDE10A would greatly accelerate the drug discovery process and assist in discovering drug candidates with diverse mechanisms of actions and better pharmacological properties, there are no currently commercial products available to the pharmaceutical industry. Codex Biosolutions has a proprietary cAMP biosensor technology (ACTOne") that has been successfully developed into a cell-based assay for screening PDE4 inhibitors in a 1536-well HTS campaign. In this SBIR phase I funding, our objective is to extend the initial success to establish a PDE10A cell-based assay that will be used by the industry to develop innovative therapeutics for schizophrenia disease. We will conduct all the research in our facilities located in Maryland and New Jersey, which are equipped with all necessary resources to complete the project. We will also have Dr. Hanting Zhang from Departments of Behavioral Medicine & Psychiatry at West Virginia University, an expert on PDE research, to consult us on the project. We propose the following four specific aims for SBIR Phase I. 1. Generate stable HEK293-CNG-TSHR-PDE10A cell line. 2. Knock out PDE4D and PDE4B genes to generate HEK293-CNG-TSHR-PDE10A-PDE4D-/--PDE4B-/- cell line (PDE10A cell line). 3. Adapt the PDE10A cell line to the 384-well HTS format. 4. Perform high-throughput screening of the compound library to evaluate the assay performance in identifying known PDE10A inhibitors. The successful completion of Phase I will pave the way to extend the same technology to other PDE isoforms, leading to the establishment of a repertoire of selective cell-based assays for individual PDE variants that will serve drug discovery projects targeting broad therapeutic areas including CNS, inflammation, metabolism, and cancer.