Project description:A major barrier to research on Parkinson’s disease (PD) is inaccessibility of diseased tissue for study. One solution is to derive induced pluripotent stem cells (iPSCs) from patients with PD and differentiate them into neurons affected by disease. We created an iPSC model of PD caused by triplication of SNCA encoding α-synuclein. α-Synuclein dysfunction is common to all forms of PD, and SNCA triplication leads to fully penetrant familial PD with accelerated pathogenesis. After differentiation of iPSCs into neurons enriched for midbrain dopaminergic subtypes, those from the patient contain double α-synuclein protein compared to those from an unaffected relative, precisely recapitulating the cause of PD in these individuals. A measurable biomarker makes this model ideal for drug screening for compounds that reduce levels of α-synuclein, and for mechanistic experiments to study PD pathogenesis. This gene expression microarray study was carried out as part of the validation process for demonstrating that the generated iPSC lines are pluripotent. 15 samples were analysed: the two parent fibroblast lines (AST denoting alpha-synuclein triplication and NAS denoting normal alpha-synuclein), two iPSC lines from each parent fibroblast line (four in total), a human embryonic stem cell line (SHEF4) and eight neuronal samples (each iPSC line differentiated into a neuronal population enriched for dopaminergic neurons, at two different time points).
Project description:A major barrier to research on Parkinson’s disease (PD) is inaccessibility of diseased tissue for study. One solution is to derive induced pluripotent stem cells (iPSCs) from patients with PD and differentiate them into neurons affected by disease. We created an iPSC model of PD caused by triplication of SNCA encoding α-synuclein. α-Synuclein dysfunction is common to all forms of PD, and SNCA triplication leads to fully penetrant familial PD with accelerated pathogenesis. After differentiation of iPSCs into neurons enriched for midbrain dopaminergic subtypes, those from the patient contain double α-synuclein protein compared to those from an unaffected relative, precisely recapitulating the cause of PD in these individuals. A measurable biomarker makes this model ideal for drug screening for compounds that reduce levels of α-synuclein, and for mechanistic experiments to study PD pathogenesis. This gene expression microarray study was carried out as part of the validation process for demonstrating that the generated iPSC lines are pluripotent. 5 samples were analysed: two clonal iPSC lines from each of two genotypes (four in total; AST denoting alpha-synuclein triplication and NAS denoting normal alpha-synuclein), a human embryonic stem cell line (SHEF4). All cultured in self-renewal conditions, mTeSR1
Project description:A major barrier to research on Parkinson’s disease (PD) is inaccessibility of diseased tissue for study. One solution is to derive induced pluripotent stem cells (iPSCs) from patients with PD and differentiate them into neurons affected by disease. We created an iPSC model of PD caused by triplication of SNCA encoding ?-synuclein. ?-Synuclein dysfunction is common to all forms of PD, and SNCA triplication leads to fully penetrant familial PD with accelerated pathogenesis. After differentiation of iPSCs into neurons enriched for midbrain dopaminergic subtypes, those from the patient contain double ?-synuclein protein compared to those from an unaffected relative, precisely recapitulating the cause of PD in these individuals. A measurable biomarker makes this model ideal for drug screening for compounds that reduce levels of ?-synuclein, and for mechanistic experiments to study PD pathogenesis. This SNP microarray study was carried out to confirm presence of SNCA triplication in the affected subject and the derived cell lines. 11 samples were analysed: genomic DNA from the two subjects in the study, the two parent fibroblast lines (AST denoting alpha-synuclein triplication and NAS denoting normal alpha-synuclein), two iPSC lines from each parent fibroblast line (four in total), a human embryonic stem cell line (SHEF4) and two neuronal samples one each from AST and NAS iPSCs).
Project description:A major barrier to research on Parkinson’s disease (PD) is inaccessibility of diseased tissue for study. One solution is to derive induced pluripotent stem cells (iPSCs) from patients with PD and differentiate them into neurons affected by disease. We created an iPSC model of PD caused by triplication of SNCA encoding α-synuclein. α-Synuclein dysfunction is common to all forms of PD, and SNCA triplication leads to fully penetrant familial PD with accelerated pathogenesis. After differentiation of iPSCs into neurons enriched for midbrain dopaminergic subtypes, those from the patient contain double α-synuclein protein compared to those from an unaffected relative, precisely recapitulating the cause of PD in these individuals. A measurable biomarker makes this model ideal for drug screening for compounds that reduce levels of α-synuclein, and for mechanistic experiments to study PD pathogenesis. This SNP microarray study was carried out to confirm presence of SNCA triplication in the affected subject and the derived cell lines.
Project description:A major barrier to research on Parkinson’s disease (PD) is inaccessibility of diseased tissue for study. One solution is to derive induced pluripotent stem cells (iPSCs) from patients with PD and differentiate them into neurons affected by disease. We created an iPSC model of PD caused by triplication of SNCA encoding α-synuclein. α-Synuclein dysfunction is common to all forms of PD, and SNCA triplication leads to fully penetrant familial PD with accelerated pathogenesis. After differentiation of iPSCs into neurons enriched for midbrain dopaminergic subtypes, those from the patient contain double α-synuclein protein compared to those from an unaffected relative, precisely recapitulating the cause of PD in these individuals. A measurable biomarker makes this model ideal for drug screening for compounds that reduce levels of α-synuclein, and for mechanistic experiments to study PD pathogenesis. This gene expression microarray study was carried out as part of the validation process for demonstrating that the generated iPSC lines are pluripotent.
Project description:A major barrier to research on Parkinson’s disease (PD) is inaccessibility of diseased tissue for study. One solution is to derive induced pluripotent stem cells (iPSCs) from patients with PD and differentiate them into neurons affected by disease. We created an iPSC model of PD caused by triplication of SNCA encoding α-synuclein. α-Synuclein dysfunction is common to all forms of PD, and SNCA triplication leads to fully penetrant familial PD with accelerated pathogenesis. After differentiation of iPSCs into neurons enriched for midbrain dopaminergic subtypes, those from the patient contain double α-synuclein protein compared to those from an unaffected relative, precisely recapitulating the cause of PD in these individuals. A measurable biomarker makes this model ideal for drug screening for compounds that reduce levels of α-synuclein, and for mechanistic experiments to study PD pathogenesis. This gene expression microarray study was carried out as part of the validation process for demonstrating that the generated iPSC lines are pluripotent.
Project description:Although α-synucleinis implicated in the pathogenesis of Parkinson’s disease and related disorders, it remains unclear whether specific conformations or levels of α-synuclein assemblies are toxic and how they cause progressive loss of human dopaminergic neurons. To address this issue, we used iPSC-derived dopaminergic neurons with a-synuclein triplication or controls where endogenous α-synuclein was imprinted into synthetic or disease-relevant conformations. We used α-synuclein fibrils generated de novo or amplified from homogenates of brains affected with Parkinson’s disease (n=3) .We found that a 2.5-fold increase in α-synuclein levels in α-synuclein gene triplication neurons promoted seeded aggregation in a dose and time-dependent fashion, which was associated with a further increase in α-synuclein gene expression.Transcriptomic analysis and isogenic correction of α-synuclein triplication revealed that intraneuronal α-synuclein levels solely and sufficiently explained vulnerability to cell death.
Project description:Althougha-synuclein is implicated in the pathogenesis of Parkinson’s disease and related disorders, it remains unclear whether specific conformations or levels ofa-synuclein assemblies are toxic and how they cause progressive loss of human dopaminergic neurons. To address this issue, we used iPSC-derived dopaminergic neurons with a-synuclein triplication or controls where endogenous a-synuclein was imprinted into synthetic or disease-relevant conformations. We used a-synuclein fibrils generated de novo or amplified from homogenates of brains affected with Parkinson’s disease (n=3) or multiple system atrophy (n=5). We found that a 2.5-fold increase in a-synuclein levels in a-synuclein gene triplication neurons promoted seeded aggregation in a dose and time-dependent fashion, which was associated with a further increase in a-synuclein gene expression. Progressive neuronal loss was observed only in a-synuclein triplication neurons seeded with brain-amplified fibrils. Transcriptomic analysis and isogenic correction of a-synuclein triplication revealed that intraneuronalalpha-synuclein levels solely and sufficiently explained vulnerability to neuronal death
Project description:Although-synuclein is implicated in the pathogenesis of Parkinson’s disease and related disorders, it remains unclear whether specific conformations or levels of-synuclein assemblies are toxic and how they cause progressive loss of human dopaminergic neurons. To address this issue, we used iPSC-derived dopaminergic neurons with -synuclein triplication or controls where endogenous -synuclein was imprinted into synthetic or disease-relevant conformations. We used -synuclein fibrils generated de novo or amplified from homogenates of brains affected with Parkinson’s disease (n=3) or multiple system atrophy (n=5). We found that a 2.5-fold increase in -synuclein levels in -synuclein gene triplication neurons promoted seeded aggregation in a dose and time-dependent fashion, which was associated with a further increase in -synuclein gene expression. Progressive neuronal loss was observed only in -synuclein triplication neurons seeded with brain-amplified fibrils. Transcriptomic analysis and isogenic correction of -synuclein triplication revealed that intraneuronal-synuclein levels solely and sufficiently explained vulnerability to neuronal death. Proximity-dependent biotinylation in living cells identified 56 differentially interacting proteins with endogenously assembled -synuclein including evasion of Parkinson’s disease-associated deglycase DJ-1 by aggregates triggered with brain amplified fibrils. Knockout of DJ-1 and related glyoxalase-1 in cell lines increased -synuclein aggregation. Similarly, methylglyoxal treatment or CRISPR/Cas9 knockout of DJ-1 in iPSC-derived dopaminergic neurons enhanced fibril-induced aggregation and cell death. Thus, toxicity of -synuclein strains depends on aggregate burden, which is determined by monomer levels and conformation which dictates differential interactomes. Our results define parameters for iPSC-based modellingof -synuclein pathology using brain amplified fibrils and demonstrate how Parkinson’s disease-associated genes influence the phenotypic manifestation of strains in human neurons.
Project description:SNCA, the first gene associated with Parkinson’s disease, encodes the α-synuclein protein, the predominant component within pathological inclusions termed Lewy bodies. We use 3D midbrain organoids, differentiated from human induced pluripotent stem cells derived from patients carrying a triplication of the SNCA gene and from CRISPR/Cas9 corrected isogenic control iPSCs. These human midbrain organoids recapitulate key features of α-synuclein pathology observed in the brains of patients with synucleinopathies. We used single cell RNA sequencing to characterize the cell types within these organoids. We find an equal proportion of neuronal and glial cells. The neuronal populations consist of dopmainergic, excitatory and inhibitory neurons in early and late stages of maturation as well as neural precursor cells. The glial populations consist of dividing radial glia, radial glia, astrocytes and early oligodendorcytes.