Development and Preclinical Efficacy of Novel Transforming Growth Factor-β1 (TGFβ1) siRNAs for Pulmonary Fibrosis

Idiopathic pulmonary fibrosis is a chronic devastating disease of unknown etiology. No therapy is currently available. A growing body of evidence supports the role of TGFβ1 as the major player in the pathogenesis of the disease. This study designed novel human- and mouse-specific siRNAs and siRNA/DNA chimeras targeting both human and mouse common sequences and evaluated their inhibitory activity in pulmonary fibrosis induced by bleomycin and lung-specific transgenic expression of human TGFβ1. Selective novel sequences of siRNA and siRNA/DNA chimeras efficiently inhibited pulmonary fibrosis, indicating their applicability as tools for treating fibrotic disease in humans. Total RNA was extracted from lung tissue from mice with bleomycin (BLM)-induced lung fibrosis treated with mouse TGFβ1 siRNAs or vehicle on different days after BLM infusion.