Fig. 4

A–F Masson’s trichrome light photomicrographs. A Photomicrograph of the CG showing normal distribution of green-stained collagen fibers in the inter-alveolar septa, perivascular and peribronchiolar. B HG showing excessive deposition of collagen fibers in inter-alveolar septa, perivascular and peribronchiolar. C CFM-TG showing apparent increase in green-colored areas within the inter-alveolar septa. D SC-PG showing limited and focal distribution of green-colored areas within the inter-alveolar septa. E SC-TG showing apparent limited distribution of green-colored areas within the inter-alveolar septa and perivascular. F Unt-G showing moderate to severe green-colored areas within the inter-alveolar septa. Masson's trichrome, scale bar (A–F) 200 µm. G–I Morphometric analysis and Statistical comparison between the studied groups according to: G Mean of septal thickness H Mean area% of collagen I Mean of alveolar area. a: Significant with CG, b: Significant with HG, c: Significant with CFM-TG, d: Significant with SC-TG, e: Significant with Unt-G. Values represent mean ± SD. Statistical significance was determined using ANOVA Test. Pairwise comparison between each 2 groups was done using Post Hoc Test (Tukey). Statistically significant at p ≤ 0.05. Error bars represent S.E.M. n = 10 for all groups. Abbreviations: CG; control group, HG; Hyperoxia group, CFM-TG; cell-free media treated-group, SC-PG; stem cell-prophylactic group, SC-TG; stem cell- treated group, Unt-G; untreated group. n = 10 in all groups