Objective    To design and produce specific stealth siRNAs and detect their inhibitive effects on TGF-β

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expression.     Methods    Three stealth siRNAs aimed directly at different sequences (stealth_48

stealth_166

stealth_594) in TGF-β

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mRNA were made. These siRNAs were transfected into BALB/c mouse lung fibroblast in vitro

then the TGF-β

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expression in those lung fibroblasts was detected by immunohistochemistry.     Results    In different time periods

the TGF-β

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expression was differently depressed by three stealth siRNAs in vitro. The inhibitory effects of stealth_166 was better than the other two

stealth siRNAs. The inhibition could be detected in 48 h

reached the highest level in 72 h and began to attenuate 96 h later.     Conclusion    The TGF-β

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expression of mouse lung fibroblasts in vitro can be depressed by synthetic stealth siRNAs. It seems possible to provide a new way for the treatment of pulmonary interstitial fibrosis.