Live microbial therapeutics for enzyme replacement therapy against homocystinuria

用于治疗同型半胱氨酸尿症的酶替代疗法的活微生物疗法

基本信息

批准号：
10384712
负责人：
Joseph Moeller Schinaman
金额：
$ 30.69万
依托单位：
PETRI BIO LLC
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-09-20 至 2023-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10384712
关键词：
Accounting Adherence Amino Acids Betaine Catalysis Characteristics Clinical Cloning Connective Tissue Cystathionine Cystathionine beta-Synthase Cysteine Data Dependence Detection Development Diet Dietary Supplementation Dietary intake Disease Disease model Doctor of Philosophy Eating Ensure Enzymes Escherichia coli Exhibits Future Genes Genetic Diseases Goals Homocysteine Homocystinuria Human Human Microbiome Impairment In Vitro Incidence Lens dislocation Lyase Measures Metabolic Metabolic Diseases Methionine Methods Modeling Mutate Mutation Outcome Phase Plasma Preclinical Drug Development Production Property Pyridoxal Phosphate Reaction Recombinant Proteins Reporting Risk Safety Serine Stroke Surveys Symptoms Testing Therapeutic Tissues Toxic effect Transgenes Transgenic Organisms Vascular Diseases Vitamin B6 Western Blotting bacterial vector base biomaterial compatibility diagnostic assay dietary restriction efficacy testing enzyme replacement therapy enzyme therapy expression vector eye center gastrointestinal gut microbiome human subject in silico in vitro Assay in vitro testing in vivo lead candidate lens microbial mouse model novel strategies programs screening stroke risk success therapeutic enzyme therapeutic protein thrombotic thrombotic complications treatment strategy tumorigenesis uptake vector

项目摘要

Project Summary The goal of this proposal is to continue the development of a synthetic live bacterial therapeutic for homocystinuria, an inborn metabolic disorder leading to accumulation of the amino acid methionine, and results in dramatically increased risk of stroke and other thrombotic conditions. Petri Bio’s approach will be capable of breaking down methionine in the gut to reduce or eliminate dependence on a methionine restricted diet and result in decreased plasma and tissue homocysteine resulting in superior clinical outcomes. The condition is estimated to occur at an incidence of 1 in 250,000, however some reports indicate a potential incidence of 1 in 65,000 when accounting for the current imprecise diagnostic assays and often subtle symptoms which may evade clinical detection until they become severe or obvious, such as lens detachment from the center of the eye. Cystathionine beta-synthase (CBS), the gene mutated in classical homocystinuria, is localized at a key regulatory branch point in the eukaryotic methionine cycle. CBS catalyzes a pyridoxal 5′-phosphate dependent beta-replacement reaction condensing serine and homocysteine (Hcy) into cystathionine that is subsequently converted to cysteine in a reaction catalyzed by cystathionine-γ-lyase (CGL, EC 4.4.1.1). Inactivation of CBS by mutation results in classical homocystinuria (HCU) which in human subjects, is characterized by a range of connective tissue disturbances including marfanoid habitus and lens dislocation, intellectual impairment, and a dramatically increased incidence of vascular disorders particularly thromboembolic complications such as stroke. Treatment strategies for pyridoxine non-responsive HCU typically attempt to lower plasma and tissue levels of Hcy by a combination of restricting dietary intake of the Hcy precursor methionine and dietary supplementation with trimethylglycine, more commonly referred to as betaine. Petri Bio, Inc. has developed a novel strategy for enzyme therapy, employing prokaryotic strains compatible with the human gut microbiome to serve as expression vectors for therapeutic protein administration. After in silico screening of bacterially-derived methionases for a number of desirable characteristics of therapeutic enzymes, ten have been cloned, expressed, and shown to reduce methionine concentrations in vitro. During this Phase I program, we will extend these studies by screening hundreds of bacterially-derived methionases in silico and subsequently cloning, expressing, and testing in vitro methionine catalysis capabilities. In vitro tests will be undertaken to measure methionase activity of these bacterial strains. After optimization of strains with high methionase activity, we will evaluate their ability to reduce methionine concentrations in vivo, as well as ameliorate the effects of methionine accumulation in a murine model of HCU. Future studies will optimize the bacterial methionase transgenes to ensure maximum activity and biocompatibility as well as select a lead candidate bacterial strain for preclinical drug development.

项目摘要该提案的目的是继续开发合成的实时细菌疗法同囊尿症，一种天生的代谢障碍，导致氨基酸金属氨酸的积累，并结果在急剧增加中风和其他血小板状况的风险中。彼得里生物的方法将能够分解肠道中的方法，以减少或消除对限制饮食的依赖和导致血浆和组织同型半胱氨酸的改善，从而产生优越的临床结局。条件是据估计发生在250,000分之一的事件中，但是一些报告表明 65,000考虑当前的浸渍诊断测定法和经常出现的微妙症状时逃避临床检测，直到它们变得严重或明显，例如镜头脱离的中心眼睛。 Cystathionine beta-synthase（CBS），在经典同囊尿中突变的基因，位于钥匙处真核甲基氨酸周期中的调节分支点。 CBS催化5'-磷酸吡啶毒素依赖性 β替代反应将丝氨酸和同型半胱氨酸（HCY）缩合到胱淀粉在由胱淀粉-γ-裂解酶催化的反应中转化为半胱氨酸（CGL，EC 4.4.1.1）。 CBS灭活突变导致经典同囊尿（HCU）在人类受试者中的特征是一系列结缔组织灾害，包括marfanoid习性和晶状体脱位，肠道损害和A 动态增加血管疾病的发生率，特别是诸如中风等血栓形成并发症。吡ido醇非反应性HCU的治疗策略通常试图降低血浆和组织水平通过限制HCY前体蛋氨酸和饮食补充的饮食摄入的组合用三甲基甘氨酸，通常称为甜菜碱。 Petri Bio，Inc。已制定了一种新颖的策略酶疗法，采用与人肠道微生物组兼容的核菌株热蛋白给药的表达向量。在细菌衍生的硅筛查中多种治疗酶特征的方法，十种已被克隆，表达，并显示可在体外降低蛋氨酸浓度。在此阶段I计划中，我们将扩展这些通过筛选硅中的数百种生物学衍生方法，然后以克隆，表达，并在体外测试甲基氨酸催化能力。将进行体外测试以测量甲糖酶这些细菌菌株的活性。在优化具有高甲证酶活性的菌株后，我们将评估它们能够降低体内蛋氨酸浓度，并改善蛋氨酸积累的作用在HCU的鼠模型中。未来的研究将优化细菌方法的翻译，以确保最大活性和生物相容性以及为临床前药物发育选择铅候选细菌菌株。