Liver-directed AAV gene therapy for PHKG2-Glycogen Storage Disease IX (GSD IX y2)

针对 PHKG2-糖原贮积病 IX (GSD IX y2) 的肝脏定向 AAV 基因治疗

基本信息

批准号：
10315138
负责人：
Rebecca Anne Gibson
金额：
$ 3.82万
依托单位：
DUKE UNIVERSITY
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：
2021-09-01 至 2024-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10315138
关键词：
Accounting Address Adolescent Age-Months Albumins Blood Glucose Breeding Capsid Case Study Cells Cessation of life Child Childhood Cirrhosis Clinical Clinical Trials Complex Corn starch preparation Data Dependovirus Diagnosis Diet Modification Dietary Intervention Disease Disease Progression Disease model Doctor of Philosophy Dose Enzymes Female Fibrosis Future Genes Genetic Glucose Glycogen Glycogen Storage Disease Glycogen Storage Disease Type IX Goals Hepatocyte Hepatomegaly Human Hypoglycemia Immune response Immunohistochemistry Immunosuppression Individual Ketones Knock-out Knockout Mice Laboratories Life Liver Liver Failure Liver Fibrosis Liver Glycogen Liver diseases Mission Modeling Mus National Institute of Child Health and Human Development Pathway interactions Patients Phenotype Phosphorylase Kinase Physicians Prevalence Primary carcinoma of the liver cells Protein Isoforms Proteins Public Health Publishing Quantitative Reverse Transcriptase PCR Recombinant adeno-associated virus (rAAV)Reporting Research Risk Scientist Serotyping Serum Severities Testing Therapeutic Time Tissues Transgenes Tropism Urine Viral Vector Weight adeno-associated viral vector base bench to bedside career clinical translation efficacy evaluation enzyme activity exome sequencing gene therapy glycogenolysis high risk in vivo innovation interdisciplinary collaboration intravenous injection liver function liver injury liver transplantation male minimally invasive mouse model novel pre-clinical preclinical efficacy preclinical evaluation promoter symptomatic improvement transduction efficiency uncooked vector

项目摘要

Liver Glycogen Storage Disease type IX has an overall estimated prevalence of 1 in 100,000 individuals, accounting for approximately 25% of all GSD cases. Liver GSD IX is caused by deficiency of the liver enzyme phosphorylase kinase (PhK) and presents with hepatomegaly, elevated liver enzymes, and hypoglycemia. PhK is a complex, hetero-tetrameric enzyme comprised of four subunits - α, β, γ, and δ - each with tissue specific isoforms encoded by different genes. The genes PHKA2, PHKB, and PHKG2 encode the liver specific isoform PhK subunits α2, β, and γ2 respectively. Until the recent availability of gene panels and exome sequencing, the diagnosis of Liver GSD IX did not allow for differentiation of these subtypes. There is growing evidence that patients with the second most common subtype, PHKG2 GSD IX (GSD IX γ2) develop severe liver disease. Of published case reports, 95.8% of patients with GSD IX γ2 reported features of liver fibrosis and/or cirrhosis, placing individuals with GSD IX γ2 at higher risk for liver failure, hepatocellular carcinoma and death. Despite the life-threatening severity of GSD IX γ2, there has been minimal research to understand disease progression or options for treatment. The first goal of this project is to characterize the phenotype of the first mouse model of PHKG2 GSD IX (GSD IX γ2). Preliminary evidence from male and female 3-month-old Phkg2-/- mice is encouraging. I have discovered that knockout mice have significantly elevated liver glycogen content, serum ALP, AST, ALT, urine Hex4, and features of hepatocyte enlargement and fibrosis compared to wild type controls. I will continue to characterize the Phkg2-/- mouse phenotype at 6, 9- and 12-months of age. By identifying the time of onset and progression of liver disease in our model, I will better understand the ideal time to deliver therapy. The second goal of this project is to evaluate the efficacy of a novel AAV gene therapy approach for reducing liver disease progression in the Phkg2-/- mouse model. Current liver-directed gene therapies utilize a recombinant adeno-associated virus serotype 8 (AAV8), based on preclinical efficacy in mice. However, recent studies have demonstrated that AAV8 has greater tropism for murine versus human hepatocytes. Our group has identified a novel capsid with high transduction rates for both human and murine hepatocytes (AAVhum.8) – making it an excellent vector for preclinical evaluation with high potential for clinical translation. The results of this project will characterize the first GSD IX γ2 mouse model, will provide preclinical evidence for a non-surgical, long-term, therapeutic option for patients with GSD IX γ2, and will inform the treatment of other pediatric genetic liver diseases.

肝糖原储存型IX的总体估计为100,000个个体中的1个。，由不同基因编码的四个人，β，γ，γ和γOrms组成的杂种酶。基因板和外显子组测序，肝GSD IX ID的诊断不允许对the术的分化。 GSDIXγ2的患者报告了肝脏和/或肝硬化的特征，使GSDIXγ2的个体面临肝脏衰竭，肝细胞癌癌和死亡的较高风险。收集PHKG2 GSD IX的第一个小鼠模型（GSD IXγ2）。与野生型对照相比，尿液和纤维化的特征是确定肝脏疾病的时间。基于鼠类与人类肝细胞的ROETRISTIS，降低了PHKG2 - / - 小鼠模型的肝脏疾病进展。对于人类和鼠肝细胞（Aavhum.8），这都使其成为临床前评估的出色载体，该项目将表征第一个GSD IXγ2小鼠模型，将提供临床前的证据长期，用于GSDIXγ2咨询函数的治疗选择，并将告知其他儿科遗传肝探测的治疗。