Fig 1.
BLM-induced pulmonary fibrosis model.
(A) Weight curves for wild-type (WT) and Scgb3a2-null (KO) mice during the entire experimental period of 21 days. Mice were intratracheally intubated bleomycin on day 0, and subjected to necropsy on day 21. Their weights were monitored daily. The mean ± SD are shown. N>10 in each group. *P<0.05, **P<0.01 by student’s t-test. (B) H&E staining (HE), Masson Trichrome staining that detects collagen fibers (MT), and Sirius Red staining for fibrosis severity (SR) of wild-type (WT) and Scgb3a2-null (KO) mice intubated with BLM or PBS as a control are shown. Representative images from N>3 in each group. Severe fibrosis is present in BLM-administered Scgb3a2-null lung. Scale bar: 200 μm. (C) Ashcroft Scores indicating the degree of fibrosis. (D) Damaged area determined by Sirius Red staining. The mean ± SD from N>3 in each group are shown. *P<0.05 by one-way ANOVA.
Fig 2.
Increased collagens in BLM-treated Scgb3a2-null lungs.
(A) Hydroxyproline content of lungs of wild-type (WT) and Scgb3a2-null (KO) mice intubated with BLM or PBS as control. The mean ± SD from N >6 in each group are shown. (B) qRT-PCR analysis of mRNAs for collagen 1a1 (Col1a1), collagen 3a1 (Col3a1), collagen 4a1 (Col4a1), and collagen 12a1 (Col12a1). Normalization control used was 18S. Relative expression levels with the mean ± SD from N>8 in each group are shown. *P<0.05, **P<0.01, and ***P<0.001 by one-way ANOVA. NS: not significant.
Fig 3.
Increased inflammatory cells in BLM-treated Scgb3a2-null lungs.
Total inflammatory cell numbers, macrophages, lymphocytes/monocytes, and neutrophils in BALF of wild-type (WT) and Scgb3a2-null (KO) mice intubated with BLM or PBS as control. The mean ± SD from N>5 in each group are shown. **P<0.01, and ***P<0.001 by one-way ANOVA. NS: not significant.
Fig 4.
Increased cytokine levels in BLM-treated Scgb3a2-null lungs.
(A) qRT-PCR analysis of mRNAs encoding IL-4, IL-5, IL-13, IL-6, CCL7, CXCL13, MMP12, TNFα, ACTA2 (α-smooth muscle actin), TGFβ, and CTGF in lungs of wild-type (WT) and Scgb3a2-null (KO) mice intubated with BLM or PBS as control. Normalization control used was 18S. (B) IL-4, IL-5, and IL-13 protein levels in BALF of wild-type (WT) and Scgb3a2-null (KO) mice intubated with BLM or PBS as control. Relative expression levels with the mean ± SD from N>8 in each group are shown. *P<0.05, **P<0.01, and ***P<0.001 by one-way ANOVA. NS: not significant.
Fig 5.
Analysis of mRNAs for surfactant proteins and SCGB proteins.
qRT-PCR was carried out to determine levels of mRNAs encoding SPA (Sftpa), SP-B (Sftpb), SP-C (Sftpc), SP-D (Sftpd), Scgb1a1 and Scgb3a2 in the lungs of wild-type (WT) and Scgb3a2-null (KO) mice intubated with BLM or PBS as control. The normalization control was 18S. Relative expression levels with the mean ± SD from N>8 in each group are shown. **P<0.01 by one-way ANOVA. NS: not significant.