The strengths of the study include the construction of the ALI mouse model by LPS airway perfusion, and the innovative idea to immunomodulate HUC-MSCs by IFN-γ to explore the protective effect of their released functional exos against ALI and the differences between IFN-γ-exos and CON-exos in terms of size, shape, particle concentration, and protein concentration. This evidence concerns the gene IFNG and acute respiratory distress syndrome.