Transcriptomic analysis of age-associated periventricular lesions reveals dysregulation of the immune response

Age-associated Periventricular white matter lesions (PVL), reflecting white matter injury, are a common feature of the ageing brain. The aim of this study was to evaluate the transcriptomic profile of PVL using microarray analysis, in order to identify which pathways and/or gene expression changes may contribute to the pathogenesis of these lesions. Total RNA was extracted from the laser capture micro-dissected periventricular region of 7 non-lesional controls, 4 pre-lesions and 7 periventricular lesional snap-frozen cases obtained from the Cognitive Function and Ageing Study neuropathology cohort. Gene expression was analysed by hybridisation to Affymetrix Human Genome U133 microarrays. Genes were considered differentially expressed if they showed a 1.2-fold change and p<0.05 across replicates of the WM groups. Microarray data was analysed using Transcriptome Analysis Console (TAC) software. Microarray data were validated using NanoString technology, to confirm the gene expression profiles in age-associated periventricular white matter. Expression profiling of Human brain periventricular region by array