Immunofluorescence staining showed that the expression levels of the fibroblast markers vimentin, α-SMA and collagen 1 in lung tissue were increased in the SiO2 group compared with the normal saline (NS) group, confirming the occurrence of pulmonary fibrosis (Fig. 1I and Additional file 1: Figure S1F, G). The gene discussed is ACTA1; the disease is pulmonary fibrosis.