Fig. 2: TSSK4 knockdown ameliorates bleomycin-induced lung fibrosis.

C57BL/6 mice were intratracheally infected with lentivirus-mediated shTSSK4 or control vectors (1.05 × 10¹⁰ infectious units (IFUs) in a volume of 30 μl per animal), and then intratracheally treated with bleomycin (3 mg/kg body weight) or the same amount of saline for a period as indicated. A H&E staining and Masson’s trichrome staining of the representative lungs from fibrosis model mice as indicated. B Quantitative mRNA expression of the fibrotic genes, including Timp1, Col3, MMP12, and α-SMA in the lungs of fibrosis models as (A) was detected through qPCR (n = 5/group). C Hydroxyproline assay of the lungs from different groups as indicated was performed (n = 5/group). D Relative body-weight loss of model mice was detected for a period of 24 days (n = 10/group). E, F IHC staining with anti-TSSK4 and anti-SP-C antibodies in the representative lungs from fibrotic model mice (E); five individual mice of each group with three random fields of (E) performed to analyze the relative signal intensity of TSSK4 and number of AT-II cells in the alveolar area through ImageJ program. The scatterplot represents the average value of each mouse (F). G Immunoblot analysis of TSSK4 and SP-C level in the lungs of different fibrotic groups at different time points as indicated, with GAPDH as internal control. Data in (B, C, D, F) are presented as mean ± s.d. In (B, C, F), **p < 0.01, n.s. p > 0.05, as analyzed by two-tailed unpaired Student’s t test. In (D), **p < 0.01, was analyzed by one-way ANOVA test. All data represent 2–3 individual experiments with similar results.