Fig. 4

Effects of WT-MSCs on the fibrotic evolution of acid aspiration acute lung injury. Collagen deposition (OH-proline assay) (a) in lung tissue in the experimental groups in 2 weeks: WT-MSCs decreased presence of fibrotic tissue while PTX3^−/−-MSCs could not (ANOVA p < 0.05 [A]; *Dunnett’s post hoc p < 0.05 vs. PBS. PBS n = 16; WT-MSCs n = 12; PTX3^−/−-MSCs n = 10)). Decreased fibrotic evolution by WT-MSCs was likely mediated by improved fibrinolysis (b) in the lungs over the days following acid aspiration acute lung injury (ANOVA p < 0.01 [B]; *Dunnett’s post hoc p < 0.05 vs. PBS. PBS n = 5; WT-MSCs n = 5; PTX3^−/−-MSCs n = 6) (PBS = acid aspiration acute lung injury + intraperitoneal (i.p.) PBS treatment in 1 h; WT-MSCs = acid aspiration acute lung injury + i.p. wild-type MSCs treatment in 1 h; PTX3^−/−-MSCs = acid aspiration acute lung injury + i.p. PTX3-deficient MSCs treatment in 1 h)