Project description:We identified diffuse lesions made of BRAF V600E-mutant CD34-immunopositive stellar cells in human samples resected to cure drug-resistant focal epilepsy. We performed single-nuclei RNAseq 5' 10X on three human brain samples (two BRAF mutant samples and one BRAF wildtype sample as control) in order to identify the molecular phenotype of CD34+ cells.
Project description:Introduction: Mosaic gain of chromosome 1q (chr1q) is a recently described driver of malformation of cortical development (MCD) and pharmacoresistant epilepsy. Hyaline protoplasmic astrocytopathy of the neocortex is a rare neuropathological finding seen in cases of pharmacoresistant epilepsy with focal cortical dysplasia or other MCD. The cell-type specificity of mosaic chr1q gain in the brain is unknown, and no data exists on the molecular signatures of hyaline protoplasmic astrocytopathy. Methods: We present a child with pharmacoresistant epilepsy who underwent epileptic focus resections at age 3 and 5 years and was found to have mosaic chr1q gain and hyaline protoplasmic astrocytopathy with partial reduction in seizure burden after the second surgery. We performed single-nucleus RNA-sequencing (snRNA-seq) of brain tissue from the second resection. Results: Remarkably, snRNA-seq showed increased expression of chr1q genes only in select populations of neurons and astrocytes. Differentially expressed genes correlating with inferred chr1q gain included AKT3 and genes associated with cell adhesion or migration. A subcluster of astrocytes demonstrated enrichment for synapse-associated transcripts, possibly linked to the astrocytic inclusions observed in hyaline protoplasmic astrocytopathy. Discussion: snRNA-seq may be used to infer the cell type-specificity of mosaic chromosomal copy number variations and identify associated gene expression alterations, which in the case of chr1q gain may involve aberrations in cell migration. Future studies using spatial profiling could yield further insights on the molecular signatures of hyaline protoplasmic astrocytopathy.
Project description:CpG methylation analysis of MeDIP DNA using Agilent Human DNA methylation Microarray slides (G4495A, AMADID 023795) Using methylated DNA immunoprecipitation microarray (MeDIP-chip) and Agilent Human DNA methylation Microarray slides (G4495A, AMADID 023795) we report genomic methylation signatures of tissues resected from Mesial temporal epilepsy (MTLE) and Focal cortical dysplasia (FCD) type II patients undergoing surgery. Control samples were obtained from the non-epileptic post mortem cases without any brain pathology