Global transcriptomic changes in human lung fibroblasts MRC5 exposed to conditioned media from RAS-activated alveolar epithelial type II (ATII) cells based on RNA-seq.

IPF (idiopathic pulmonary fibrosis), a progressive lung disease with an unmet need for treatment, causes increased morbidity and mortality worldwide. Abnormal wound healing is strongly implicated in IPF, but the underlying mechanisms remain poorly understood. Here we reported that aberrant epithelial-mesenchymal crosstalk provides self-sustaining pro-fibrotic signals in IPF. By performing RNA-sequencing (RNA-seq) in human lung fibroblasts MRC5 treated with either conditioned media (CM) from control or 4-OHT (4-hydroxytamoxifen) - treated ATIIER:KRASV12 cells (kindly provided by Prof Julian Downward, The Francis Crick Institute, UK), in which addition of 4-OHT acutely activates RAS pathway (Yao et al. Cell Death & Differentiation 2019), we identify several IPF-related pathological alterations. These include increases in GO terms related to extracellular matrix (ECM) and collagen, cell migration, and inflammatory response. Our data suggest that RAS-activated ATII cells crosstalk to MRC5 lung fibroblasts to augment their activation and migration. To assess the global transcriptomic changes in lung fibroblasts exposed to conditioned media from RAS-activated ATII cells. In the control group (control), MRC5 lung fibroblasts were dosed with conditioned media collected from control ATIIER:KRASV12 cells for 24 hours. In the 4-OHT group (4-OHT), MRC5 lung fibroblasts were dosed with conditioned media collected from 4-OHT-treated ATIIER:KRASV12 cells for 24 hours. RAS activation was induced by addition of 4-OHT to ATIIER:KRASV12 cells for 24 hours, and conditioned media were then collected. After treatment, MRC5 cells were subjected to RNA-seq (n=3 for each group).