Fig. 6

PαS MSC suppress in vivo expansion of respiratory IFN-γ⁺ and IL-17⁺ CD4⁺ T cells after K. pneumoniae infection. Representative flow cytometry analysis of intracellular IL-17 expression in respiratory CD4⁺ T cells in K. pneumoniae-infected animals treated with PαS MSC versus mock-treated infected animals at d5 p.i. (a). Iso refers to isotype-matched fluorescence minus-one controls to assess background staining. Relative frequencies and absolute numbers of cytokine expressing respiratory CD4⁺ and CD8⁺ T cell subsets in K. pneumoniae-infected (Kpn) animals treated with PαS MSC versus mock-treated infected animals (b-c). Mean ± SEM; n ≥ 4; *p < 0.05 versus mock-treated infected controls. Data from n ≥ 2 (A-C) experiments