Fig. 4

Low-concentration sTN-C supplementation enhanced the proliferation and migration of epithelial cells. A The overexpression of sTN-C in the supernatant of transfected 293 T cells was verified by Western blotting. B CCK-8 assay for determining the viability of MLE-12 cells incubated for 24 h under normoxia after low-dose sTN-C supplementation (2 ng/mL). C, E. CCK-8 assay was used to assess the viability of MLE-12 cells or BEAS-2B cells incubated for 24 h under 85% hyperoxia following low-dose supplementation with sTN-C (2 ng/mL) and TN-C neutralizing antibodies. D, F EdU assays were used to assess the proliferation of MLE-12 and BEAS-2B cells incubated for 24 h under 85% hyperoxia following low-dose supplementation with sTN-C (2 ng/mL) and TN-C neutralizing antibodies (2 ng/mL). Scale bars = 50 μm. G-H A live cell imaging system was used to observe the migration ability of alveolar epithelial cells at the scratch edge after a 90-min incubation period under normoxia following the addition of low-dose sTN-C (2 ng/mL). Scale bars = 50 μm. The average migration speed of individual cells was analyzed using ImageJ. All experiments were repeated at least 3 times. ***P < 0.001, **** P < 0.0001