SCGB3A2 suppresses bleomycin-induced pulmonary fibrosis through activation of STAT1 and up-regulation of SMAD7

We report for the first time that secretoglobin (SCGB) 3A2, a novel cytokine-like molecule, predominantly expressed in pulmonary airways epithelium, drastically reduced the severity of lung fibrosis using bleomycin-induced mouse model. DNA microarrays were performed using RNAs isolated from mouse lungs in two experiments. In the first experiments, mice were adminitered intravenously SCGB3A2 or PBS once daily for a week, starting on day 14 after BLM administration, and in the second experiments, SCGB3A2 or PBS was administered intravenously for 12 hrs.