Fig. 5

TSG-6 reverses hyperoxia-induced pulmonary inflammation and altered morphology in the BPD mice. a Schematic representation of BPD mouse model and TSG-6 injection regime. 5 μg of rhTSG-6 resuspended in total 100 μl of PBS was injected into each neonatal mouse at PN2 and PN4. b-d Histograms showing BALF total cell count (b), BALF absolute neutrophil count (c), total BALF protein (d) in RA, BPD, PBS-injected and TSG-6-injected BPD mice at PN14. e Representative images of lung histology with H&E stain from the four experimental groups, RA (I), BPD (II), BPD + PBS (III), BPD + TSG-6 (IV). Asterisks depict the increased alveolar simplification in the BPD and PBS-injected BPD mice as compared to RA. ×200 magnification, Scale bar: 50 μm. f-k Histograms showing the mean chord length (f), septal thickness (g), alveolar area (h), number of branches (i), junctions (j), junction voxels (k) in lungs of RA, BPD, PBS-injected, TSG-6-injected BPD mice. All values are expressed as mean ± SEM; four experiments, N = 3–8 mice per group; one-way ANOVA with Tukey’s post hoc correction; *p < 0.05; **p < 0.01; ***p < 0.001; ****p < 0.0001. BALF bronchoalveolar lavage fluid, BPD bronchopulmonary dysplasia, CM conditioned medium, EXO exosomes, i.p. intraperitoneal, MSC mesenchymal stem cell, PAAT pulmonary artery acceleration time, PAET pulmonary artery ejection time, PBS phosphate-buffered saline, PN postnatal, RA room air, TSG-6 tumor necrosis factor alpha-stimulated gene-6