Single chain Fragments of variable regions in the treatment of Familial ALS

描述（由申请人提供）：大约10%的肌萎缩侧索硬化症（ALS）病例是家族性的（FALS），其中20%的病例是由称为超氧化物歧化酶1型（SOD 1）的酶突变引起的。一些证据表明，在FALS中运动神经元死亡的原因不是由于突变的SOD 1蛋白酶活性的缺乏，而是由于突变的（MT）酶的毒性。一个有吸引力的假设是，SOD 1蛋白中的突变导致其错误折叠，错误折叠导致SOD 1在细胞内聚集，并干扰对细胞存活重要的正常蛋白质-蛋白质相互作用。与该提议相关的是最近的证明，即MTSOD 1特异性的单克隆抗体在FALS的MTSOD 1转基因小鼠模型中可以是治疗有效的。可能的是，针对MTSOD 1的抗体的可变区的单链片段（scFv）可以补充抗MTSOD 1单克隆抗体，因为scFv提供了细胞内表达的机会（作为胞内抗体）。我们已经分离出了许多针对SOD 1的抗体的scFv，包括针对A4 V MTSOD 1的scFv-北美最常见的SOD 1突变，并且通常在不到一年的时间内导致死亡。我们现在计划：测试通过转染或病毒载体递送的scFv是否降低MN细胞系和原代MN中MTSOD 1表达的聚集体形成和/或毒性;测试通过复制缺陷型重组腺相关病毒（AAV）递送到FALS转基因小鼠中的scFv是否减少MTSOD 1聚集，这些研究可能会阐明细胞死亡的原因，并为SOD 1突变的FALS患者确定可能的治疗方法。了解导致FALS运动神经元死亡的机制及其治疗方法可能会指导我们理解非遗传性ALS -特别是最近的信息表明，SOD 1的生化变化可能导致非遗传性ALS疾病。 公共卫生相关性： 肌萎缩性侧索硬化症（ALS）是一种绝望的疾病，其中没有治愈或有效的治疗。该提议涉及针对在某些家族性ALS病例中突变的蛋白质产生抗体，并且该蛋白质与散发性ALS的发展有关。我们产生的抗体可能有助于了解ALS的病因，并可能为遗传性ALS和散发性ALS的治疗提供方向。

DESCRIPTION (provided by applicant): Approximately 10% of cases of amyotrophic lateral sclerosis (ALS) are familial (FALS), and 20% of these cases are caused by mutations in an enzyme called superoxide dismutase type 1 (SOD1). Several lines of evidence have made it clear that the reason for motor neuron death in FALS is not due to a deficiency in enzymatic activity by the mutated SOD1 protein, but due to toxicity of the mutant (MT) enzyme. One attractive hypothesis is that the mutations in the SOD1 protein cause it to misfold, and the misfolding leads to aggregation of SOD1 within the cell and an associated interference with normal protein-protein interactions important for cell survival. Relevant to this proposal is the recent demonstration that monoclonal antibodies that are MTSOD1-specific can be therapeutically effective in a MTSOD1 transgenic mouse model of FALS. It may be that single chain fragments of variable region (scFvs) of antibodies directed against MTSOD1 can complement anti-MTSOD1 monoclonal antibodies since scFvs provide the opportunity for expression intracellularly (as intrabodies). We have isolated a number of scFvs of antibodies directed against SOD1, including an scFv that is directed against A4V MTSOD1 - the most common mutation of SOD1 seen in North America, and one that usually causes death in less than a year. We now plan to: prepare additional scFvs against wild type and MTSOD1; test whether scFvs delivered by means of transfection or virus vector delivery decrease aggregate formation and/or toxicity of MTSOD1 expression in a MN cell line and primary MNs; test whether scFvs delivered by means of a replication-deficient recombinant adeno-associated virus (AAV) into FALS transgenic mice decrease MTSOD1 aggregation, delay the onset or slow the progression of disease These studies may clarify the reasons for cell death as well as identify possible therapeutic approaches for FALS patients with SOD1 mutations. The knowledge of the mechanisms responsible for motor neuron death in FALS and its treatment may guide us in our understanding of non-inherited ALS - especially since recent information suggests that biochemical changes in SOD1 may contribute to disease in non-inherited ALS. PUBLIC HEALTH RELEVANCE: Amyotrophic lateral sclerosis (ALS) is a desperate disease in which there is no cure or effective treatment. This proposal involves raising antibodies directed against a protein that is mutated in some cases of familial ALS and has been implicated in the development of sporadic ALS. The antibodies that we raise may help understand the cause of ALS and potentially provide a direction for treatment of inherited ALS as well as sporadic ALS.