The accurate detection of ultralow allele frequency variants in DNA samples is of interest in both research and medical settings, particularly in liquid biopsies where cancer mutational status is monitored from circulating DNA. Next-generation sequencing (NGS) technologies employing molecular barcoding have shown promise but significant sensitivity and specificity improvements are still needed to detect mutations in a majority of patients before the metastatic stage. To address this we present analytical validation data for ERASE-Seq (Elimination of Recurrent Artifacts and Stochastic Errors), a method for accurate and sensitive detection of ultralow frequency DNA variants in NGS data.
View Article and Find Full Text PDFBackground: ChIP-seq is the primary technique used to investigate genome-wide protein-DNA interactions. As part of this procedure, immunoprecipitated DNA must undergo "library preparation" to enable subsequent high-throughput sequencing. To facilitate the analysis of biopsy samples and rare cell populations, there has been a recent proliferation of methods allowing sequencing library preparation from low-input DNA amounts.
View Article and Find Full Text PDFEmbryonic stem (ES) cell-derived photoreceptors are a promising cell source for enhanced in vitro models of retinal degenerative diseases, but the more differentiated characteristics of retinal cells do not typically develop in dissociated cell cultures. Therefore, we have reconstructed organized retinal tissue by seeding dissociated cells into an array of aligned units that more faithfully mimics the retina. We solvent-processed poly(lactic-co-glycolic acid) (PLGA) into a microchannel scaffold format to achieve this geometric constraint.
View Article and Find Full Text PDFBackground: Inherited and acquired retinal degenerations are frequent causes of visual impairment and photoreceptor cell replacement therapy may restore visual function to these individuals. To provide a source of new retinal neurons for cell based therapies, we developed methods to derive retinal progenitors from human ES cells.
Methodology/physical Findings: In this report we have used a similar method to direct induced pluripotent stem cells (iPS) from human fibroblasts to a retinal progenitor fate, competent to generate photoreceptors.