The technique thus allows cells to be selected based on multiple parameters. Intracellular markers can be accessed using cell permeabilization. Fluorescence-activated cell sorting (FACS) involves labeling the cell proteins on which cell selection is based with fluorescent molecules attached to target-specific antibodies.Let us consider the most commonly used techniques. The performance of each method is defined by its efficiency (how many cells can be isolated per unit of time), purity (the fraction of target cells collected) and recovery (the fraction of target cells collected compared to the total number of target cells initially available). Isolation of cells and basic sample processingĬells can be isolated using different methods, 7, 8 the choice of which mainly depends on the nature of the sample and the processing steps required after the cells’ isolation. In all cases, however, the resulting sequencing material is a library of barcoded DNA or cDNA for each cell which can then be sequenced on the chosen sequencing platform. Depending on the genetic material of interest, the sample preparation procedure differs slightly. This article explores how this technology works and what it tells us.įigure 2: Single cell sequencing workflow. While relatively recent, one of the most interesting ones is single cell sequencing. 4 A variety of sequencing methods have been developed for specific applications. During the next two decades, sequencers went through rapid evolution, optimizing, to different extents, parameters such as speed, accuracy, sequencing depth and read length. They have been named second-generation or next-generation sequencers to distinguish them from the first experimental ones, and allowed the sequencing of entire genomes.
Single cell transcriptome sequencing (single cell RNA sequencing, single cell RNA-seq, or scRNA seq)Ĭombining single cell sequencing with other techniques and single cell technologyĬommercial DNA sequencers were first produced in the late 1990s. Isolation of cells and basic sample processing What is single cell sequencing and what is single cell RNA sequencing?