Mature brain organoid platform for therapeutic screening for ALS/FTD

摘要 Synapticure正在开发一种新的患者衍生的3D平台，用于TDP的高保真建模和筛选 肌萎缩侧索硬化症(ALS)和额颞叶痴呆的43种蛋白病变和相关生物标志物 (FTD)。Synapticure的成熟脑器官(MBOrgs)由来自患者的关键神经细胞组成- 诱导多能干细胞(IPSCs)，并被定制组装成人脑共培养，允许它们 总结几个ALS/FTD疾病的特征，这些特征在任何现有的体外模型中都没有被全面地看到。 保守地说，16000名美国人受到肌萎缩侧索硬化症的影响，而多达3万人患有FTD，其发病率 认知和身体损伤也很严重。目前，肌萎缩侧索硬化症的有效诊断和治疗 和FTD是缺乏的，新的疗法在人类身上的应用效果很差，尽管在 体外和体内的临床前研究。迫切需要这两种疾病的准确模型来推动 开发新的生物标记物、诊断/预后工具和治疗学。Synapticure的创新MBOrg Platform通过提供一种高度可重复性的方法来准确地创建3D mbOrg，从而满足了这一需求 反映与ALS和FTD相关的疾病状态，包括现有 模特们。该平台使用类似工程的方法，在其中生成蜂窝组件并 分别进行分化，然后组装成满足特定疾病模型需要的有机体。 Synapticure能够从成熟的人类星形胶质细胞(IA)和同质皮质样细胞中形成MBOrgs 神经元(In)具有确定的数量和比例，为成熟的星形胶质细胞提供了类似于 在健康的人脑中，概括了ALS的关键特征，如衰老相关疾病病理从未见过 之前报道过体外实验。Synapticure和我们的合作者最近成功地将IPSC派生的 小胶质细胞转化为mBOrgs，添加小胶质细胞是该计划的优先事项。Synapticure的3D模型已经被 通过检测TDP-43蛋白病变得到验证，这种蛋白病变在~97%的ALS和~45%的FTD中起作用 案子。这包括对TDP-43的定位和磷酸化的评估，以及对TDP-43的错误剪接 Stathmin-2(STMN2)，一种新近鉴定的TDP-43蛋白病的生物标志物。Synapticure的第一阶段证据 Of Concept项目寻求推进2D到3D筛选管道，以识别此类额外的化合物 通过以下具体目标拯救特定表型：1)建立并验证2D屏幕显示 TDP-43蛋白病变和抢救；2)使用3D确认候选治疗方案的3D疗效 MBOrgs评估候选治疗方案抢救非应激性TDP-43蛋白病的能力 诱导性。在该项目成功完成后，在未来的第二阶段应用中，Synapticure将期待 将平台扩展到患者来源的细胞，并包括其他相关细胞类型，确认能够进行筛选 针对广泛遗传背景的化合物，作为实现ALS/FTD个性化治疗的第一步。

Abstract Synapticure is developing a novel patient-derived 3D platform for high-fidelity modeling and screening of TDP- 43 proteinopathy and associated biomarkers for amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Synapticure’s mature brain organoids (mbOrgs) are composed of key neural cells derived from patient- induced pluripotent stem cells (iPSCs) and are custom assembled into human brain co-cultures, allowing them to recapitulate several ALS/FTD disease features not seen comprehensively in any existing in vitro models. Conservatively, 16,000 Americans are affected by ALS, while up to 30,000 suffer from FTD, and the morbidity and cognitive and physical impairments are significant. Currently, effective diagnostics and treatments for ALS and FTD are lacking, and newer therapies have translated poorly to humans, despite showing great promise in in vitro and in vivo preclinical studies. Accurate models of both diseases are critically needed to advance the development of novel biomarkers, diagnostic/prognostic tools, and therapeutics. Synapticure’s innovative mbOrg platform answers this need by providing a highly reproducible approach for creating 3D mbOrgs that accurately reflect disease states relevant to ALS and FTD, including matched pathological features not seen in existing models. The platform uses an engineering-like approach, where cellular components are generated and differentiated separately and then assembled into organoids that meet the needs of a specific disease model. Synapticure has the ability to form mbOrgs from mature human astrocytes (iA) and homogeneous cortical-like neurons (iN) in defined numbers and ratios, providing a 3D environment with mature astrocytes similar to those in the healthy human brain and recapitulating key features of ALS such as aging-related disease pathology never before reported in vitro. Synapticure and our collaborators have recently successfully incorporated iPSC-derived microglia into mbOrgs, and adding microglia is a priority for this program. Synapticure’s 3D models have been validated by assaying TDP-43 proteinopathy, which contributes to disease in ~97% of ALS and ~45% of FTD cases. This includes evaluation of TDP-43 localization and phosphorylation, as well as the mis-splicing of stathmin-2 (STMN2), a recently characterized biomarker of TDP-43 proteinopathy. Synapticure’s Phase I proof of concept project seeks to advance a 2D to 3D screening pipeline for identifying such additional compounds that rescue specific phenotypes via the following Specific Aims:1) Establish and validate a 2D screen showing TDP-43 proteinopathy and rescue, and 2) Confirm efficacy of therapeutic candidates in 3D by using the 3D mbOrgs to evaluate the ability of the therapeutic candidates to rescue TDP-43 proteinopathy that is not stress induced. Following successful completion of this project, in a future Phase II application, Synapticure will look to expand the platform to patient-derived cells and include other relevant cell types, confirming the ability to screen compounds against a broad genetic background as a first step towards personalized treatment for ALS/FTD.