Analytical Validation of Non-native Transthyretin (NNTTR) As A Candidate Biomarker for Transthyretin Amyloidoses (ATTR)

项目说明 转甲状腺素(TTR)淀粉样变性(ATTR)是由错误折叠引起的进行性致死性疾病， 同源四聚体甲状腺激素转运蛋白TTR突变体和野生型的聚集和沉积 由肝脏、脉络丛和视网膜分泌的蛋白质。以原发性多发性神经病(FAP)为表现的ATTR可以 影响外周、自主神经和中枢神经系统(CNS)。传统上以临床诊断为主。 观察，组织活检刚果红染色，结合基因检测。Attr-FAP被广泛使用 诊断不足。ATTR-FAP患者的首发症状和诊断之间通常有2-3年的差距。 影响中枢神经系统的ATTR很难诊断，常被忽视或误诊。近几年来的研究进展 针对Attr的疾病修正疗法的开发和商业化强调了以下需求 早期明确诊断。从目前的研究中可以清楚地看出，早期发现和治疗attr和 其他淀粉样蛋白疾病导致更好的临床结果，通过阻止疾病进展和 提高了生活质量。尽管治疗突变是可取的，但在实践中，实现 为早期治疗提供一个客观的起点。针对Attr-FAP的临床试验相对采用了 周围神经功能变化相对缓慢的粗略临床测量需要12-24个月的 观察以了解可测量的疗效。药物开发过程将大大缩短 监测病理相关的、可量化的、药效学生物标志物的水平。 与阿尔茨海默病中所见的Aβ聚集一样，Ttr的错误折叠/聚集发生在数年内 在出现症状和可检测到的淀粉样蛋白形成之前。这些独特的流传着的非本土 TTR(NNTTR)结构被认为是产生神经毒性的近端致病分子，并且 组织损伤，使其成为早期患者识别的理想候选生物标记物，并作为药物- 监测疾病进展和药物反应的动态标记物。我们已经开发了一种夹心酶联免疫吸附试验 使用针对NNTTR的专有抗体进行检测。我们已经证明，NNTTR免疫分析可以 快速准确地识别症状前携带者和V30M-TTR(最常见的突变)和其他 ATTR-FAP患者采用血浆和脑脊液(CSF)样本。NNTTR水平在以下方面增加 症状前携带者的血浆在症状出现前和在接受不同治疗的患者中降低 Attr治疗学的类别。在此，我们建议对NNTTR进行全面的分析验证 候选生物标记物，旨在开发一种可靠的NNTTR定量测量方法。如果我们成功了， 将继续进行进一步的临床验证和资格鉴定。所得到的NNTTR生物标记物/化验可用于 作为早期诊断，专门识别哪些患者可以从靶向ATTR疗法中受益，如 如他法米迪、帕西兰和诺特生，以及目前正在开发的其他ATTR疗法， 可能在治疗和预防中枢神经系统疾病方面更有效。

Project Description The transthyretin (TTR) Amyloidoses (ATTR) are progressive fatal diseases caused by the misfolding, aggregation and deposition of mutant and wild-type forms of TTR, a homotetrameric thyroxin transporting protein secreted by the liver, choroid plexus and retina. ATTR presenting as primary polyneuropathy (FAP) can affect the peripheral, autonomic and central nervous systems (CNS). It is traditionally diagnosed by clinical observation, Congo red staining of tissue biopsies, coupled with genetic testing. ATTR-FAP is widely underdiagnosed. ATTR-FAP patients commonly have a 2-3-year gap between first symptoms and diagnosis. ATTR affecting the CNS is difficult to diagnose and is often ignored or misdiagnosed. Recent advances in the development and commercialization of disease modifying therapeutics targeting ATTR underline the need for early and specific diagnosis. It is clear from current studies that early detection and treatment of ATTR and other amyloid diseases leads to superior clinical outcomes, as measured by arrest of disease progression and improved quality of life. As much desirable as is to treat the mutations, in practice, it is imperative to implement a objective initiation point for early treatment. Clinical trials targeting ATTR-FAP have employed relatively coarse clinical measures of peripheral nerve function which change relatively slowly requiring 12-24 months of observation to see measurable efficacy. The drug development process would be significantly shortened by monitoring the level of a pathologically related, quantifiable, pharmacodynamic biomarker. As with the Aβ aggregation seen in Alzheimer’s disease, misfolding/aggregation of TTR occur years before the emergence of symptoms and detectable amyloid formation. These distinctive circulating non-native TTR (NNTTR) structures are believed to be the proximal pathogenetic molecules producing neurotoxicity and tissue damage, making them ideal candidate biomarkers for early patient identification, and as a pharmaco- dynamic marker to monitor disease progression and drug response. We have developed a sandwich ELISA assay using proprietary antibodies specific for NNTTR. We have shown that the NNTTR immunoassay can rapidly and accurately identify pre-symptomatic carriers and V30M-TTR (most common mutation) and other ATTR-FAP patients using plasma and cerebrospinal fluid (CSF) samples. NNTTR levels are increased in plasma of pre-symptomatic carriers before symptom onset and are reduced in patients receiving different classes of ATTR therapeutics. Herein, we propose to conduct a full analytical validation of the NNTTR candidate biomarker, aiming at developing a robust quantitative measurement of NNTTR. If we are successful, further clinical validation and qualification will be pursued. The resulting NNTTR biomarker/assay can be used as an early diagnostic to specifically identify patients who can benefit from targeted ATTR therapeutics, such as tafamidis, patisiran, and inotersen, as well as additional ATTR therapeutics, currently in development, that may be more effective in the treatment and prevention of CNS disease.