Project description:We used a modified 5i/L/FA system to generate transgene-free naïve iPSCs directly from the fibroblasts of a patient suffering from β-thalassemia and further demonstrated efficient gene correction with a CRISPR/Cas9 system, which provides an improved strategy for personalized treatment of β-thalassemia.
Project description:Dilated cardiomyopathy (DCM) is the second most common cause for heart failure with no cure except a high-risk heart transplantation. Approximately 30% of DCM patients harbor heritable mutations which are amenable to CRISPR-based gene therapy1. However, challenges related to delivery of the editing complex and off-target concerns hamper the broad applicability of CRISPR agents in the heart2. We employed a combination of the viral gene transfer vector AAVMYO with superior targeting specificity of heart muscle tissue3 and CRISPR base editors to repair patient mutations in the cardiac splice factor Rbm20, which cause aggressive and arrhythmogenic DCM4. Using optimized conditions, we could improve splice defects in human iPSC-derived cardiomyocytes (iPSC-CMs) and repair >70% of cardiomyocytes in two Rbm20 knock-in mouse models that we generated to serve as an in vivo platform of our editing strategy. Treatment of juvenile mice restored the localization defect of RBM20 in 75% of cells and splicing of RBM20 targets including TTN. Three months after injection, cardiac dilation and ejection fraction reached wildtype levels. Single-nuclei RNA sequencing (snRNA-seq) uncovered restoration of the transcriptional profile across all major cardiac cell types and whole-genome sequencing (WGS) revealed no evidence for aberrant off-target editing. Our study highlights the potential of base editors combined with AAVMYO to achieve gene repair for treatment of hereditary cardiac diseases.
Project description:CD3δ SCID is a devastating inborn error of immunity caused by mutations in CD3D, encoding the invariant CD3δ chain of the CD3/TCR complex necessary for normal thymopoiesis. We demonstrate an adenine base editing (ABE) strategy to restore CD3δ in autologous hematopoietic stem and progenitor cells (HSPC). Delivery of mRNA encoding a laboratory-evolved ABE and guide RNA into CD3δ SCID patient’s HSPCs resulted in 71.2±7.85% (n=3) correction of the pathogenic mutation. Edited HSPCs differentiated in artificial thymic organoids produced mature T cells exhibiting diverse TCR repertoires and TCR-dependent functions. Edited human HSPCs transplanted into immunodeficient mice showed 88% reversion of the CD3D defect in human CD34+ cells isolated from mouse bone marrow after 16 weeks, indicating correction of long-term repopulating HSCs. These findings demonstrate preclinical efficacy of ABE in HSPC for the treatment of CD3δ SCID, providing a foundation for the development of a one-time treatment for CD3δ SCID patients.
Project description:To investigate whether the microRNA expression profile changes with modulation of severity, GlycophorinA positive cells were isolated by immunomagnetic procedure from peripheral blood of two Eb thalassemia patients with same b globin gene mutation but differing in transfusion requirment. MicroRNA expression profile of the two samples were monitored. Agilent one-color experiment,Organism: Human ,Agilent-019118 Human miRNA Microarray Labeling kit: Agilent miRNA labeling reagent and Hybridization Kit Cat # 5190-0408
Project description:β-thalassemia major can be caused by homozygous mutations of the HBB gene, most of the cases are inherited from parents who both have β-thalassemia minor. Herein, we show that a mosaic paternal uniparental isodisomy of chromosome 11p14.3-15.5 is associated with β-thalassemia major in a patient with β-thalassemia minor-that evolved to β-thalassemia major. From this case, we suggest that analysis of HBB gene for non-hematopoietic tissues should be performed in late-onset β-thalassemia major patients. Experiment Overall Design: This study is to evaluate the cause of delay-onset β-thalassemia major in our patient. Patients peripheral blood, hair follicle, and oral mucosa, and her parents pripheral blood samples were analyzed.