The immunohistochemical staining results showed a significant increase of macrophages in quantity and autophagy level as indicated by enhanced LC3B expression and reduced SQSTM1 expression in WT mice treated with SiO2 suspension for 1 month compared with that of mice in the control group; however, Bbc3 knockout decreased the autophagy levels in the silicosis model (Figure 4e and Supplementary Figure S3D). The gene discussed is SQSTM1; the disease is silicosis.