Inhibitory effect of interferon for silica-induced stimulation in rat lung fibroblast

OBJECTIVE To evaluate the inhibitive effect of interferon in rat lung fibroblast(LF)exposed to silica.METHODS Silica suspension was used to stimulate AM for 24 hours.Then centrifuge was used to remove silica and collect supernatant.LF was stimulated by the collected supernatant for 24h with interferon(10 U/ml,100/ml and 1 000 U/ml).The positive control was treated without interferon.AM supernatant without silica was used in negative control group.The mRNA expression of the α-smooth muscle actin(α-SMA),(collagenⅠ)COL Ⅰ and(collagen Ⅲ)COL Ⅲ were detected by using real-time PCR,and the protein level of the COL Ⅰ and COL Ⅲ was examined by ELISA.RESULTS Compared to positive control group,the mRNA of α-SMA,collagenⅠ and collagen Ⅲ were decreased in cultured supernatant exposed to interferon at 1 000 u/ml(P﹤0.01).The concentration of collagen,collagen Ⅲ and total protein were decreased compared to positive control(P﹤0.01).CONCLUSION Interferon could inhibit the effect of LF stimulated by silica by decreasing the levels of COL Ⅰ and COL Ⅲ.