Figure 4.

BBC3-mediated autophagy processes in mouse silicosis model. (a and b) Representative Western blot and densitometric analyses showing that Bbc3 knockout decreased the LC3BII expression, but increased the SQSTM1 expression in bone marrow-derived macrophages (BMDMs) exposed to SiO₂. Data are presented as the mean±S.E.M. (n=3); *P<0.05; **P<0.01 versus the WT group; ^##P<0.01; ^###P<0.001 versus the WT+SiO₂ group (two-way ANOVA). (c and d) Representative Western blot and densitometric analyses showing that BafA1 further increased accumulation of LC3BII induced by SiO₂ in BMDMs. Data are presented as the mean±SEM (n=3); *P<0.05; **P<0.01 versus the control group; ^##P<0.01 versus the SiO₂ group (two-way ANOVA). (e) Immunohistochemical staining of WT and Bbc3 KO mouse lung tissue showing autophagy intensity. The results indicated that the loss of BBC3 reduced the number of macrophages and the expression of SQSTM1 in lung tissue sections. Scale bar=20 μm. Images are representative of several individuals from each group (n=4). (f) Representative western blot showing the expression of BBC3 in macrophages from healthy donors and silicosis patients. (g) Densitometric analyses of macrophage samples from five healthy donors and five silicosis patients suggested that BBC3 expression was elevated in macrophages from silicosis patients. Data are presented as the mean±S.E.M.; *P<0.05 versus the corresponding healthy control group (Student's t-test). (h) Representative western blot showing the expression of BECN1 and LC3B in macrophages from healthy donors and silicosis patients. (i) Densitometric analyses of macrophage samples from five healthy donors and five silicosis patients suggested that BECN1 and LC3BII expression was elevated in macrophages from silicosis patients. Data are presented as the mean±SEM; *P<0.05 versus the corresponding healthy control group (Student's t-test)