High throughput quantitative whole transcriptome analysis of distal mouse lung epithelial cells from various developmental stages (E14.5, E16.5, E18.5 and adult)

We used microfluidic single cell RNA-seq on 198 individual mouse lung epithelial cells at 4 different stages throughout development to measure the transcriptional states which define the developmental and cellular hierarchy of the distal mouse lung epithelium. We classified 80 cells comprising the distal lung epithelium at E18.5 into distinct populations using an unbiased genome-wide approach that did not require a priori knowledge of the underlying cell types or prior purification of cell types. This “reverse tissue engineering” approach confirmed the basic outlines of the conventional model of cell type diversity in the distal lung and led to the discovery of a large number of novel transcriptional regulators and cell type markers that discriminate between the different populations. Moreover, we reconstructed the steps during maturation of bipotential progenitors into both alveolar lineages based on the presence of undifferentiated, differentiated as well as differentiation intermediate cells at the single time point E18.5. Finally, we followed Sftpc-positive cells throughout their lifecycle (E14.5, E16.5, E18.5, adult) and identified 7 gene sets that differentiate between the multipotential, bipotential, mature, as well as intermediate states of the AT2 lineage.