Single-cell RNA-sequencing of bronchoscopy specimens: development of a rapid, minimal-handling protocol

Single-cell RNA-sequencing (scRNA-seq) is an important tool for understanding disease pathophysiology, including airways diseases. Currently, the majority of scRNA-seq studies in airways diseases have used invasive methods (airway biopsy, surgical resection) which carry inherent risks and thus present a major limitation to scRNA-seq investigation of airway pathology. Bronchial brushing, where the airway mucosa is sampled using a cytological brush, is a viable, less invasive method of obtaining airway cells for scRNA-seq. Here we are describing the development of a rapid and minimal-handling protocol for preparing single cell suspensions from bronchial brush specimens for scRNA-seq. Our optimized protocol maximises cell recovery and cell quality, and may facilitate large-scale profiling of the airway transcriptome at single cell resolution. Lay abstractSingle-cell RNA-sequencing (scRNA-seq) measures the gene expression of individual cells, and may be useful for understanding disease processes. scRNA-seq may be used to investigate lung diseases, but using invasive methods such as biopsy or surgery limits our ability to conduct large research studies. Bronchial brushing, where a soft brush is used to collect cells from inside the lungs, is a safer method but we need a better way to isolate individual cells from the brush specimens. We developed a method that is faster and involves less handling of the specimens compared to other published methods. Our method may therefore be useful for conducting large scRNA-seq studies in lung diseases.