Fig. 7: Ly6C⁺Ly6G⁺CD4⁺ T cells increase the phagocytosis and bactericidal activity of macrophages.

A RAW264.7 macrophages were co-cultured with IL-21, Ly6C⁺Ly6G⁺CD4⁺ T cells, and Ly6C⁺Ly6G^-CD4⁺ T cells for 84 h. After co-culture the RAW264.7 macrophages were stimulated with APP (MOI = 10) for 30 min, APP content in macrophages were analyzed. B, C The proportion of Ly6C⁺Ly6G⁺CD4⁺T cells in CD4⁺ T cell population in the lung of ICR mice infected with K. pneumoniae and E. coli at 0, (without infection), 6, 12, 24, and 48 h, respectively. D, E RAW264.7 macrophages were co-cultured with IL-21, Ly6C⁺Ly6G⁺CD4⁺ T cells, and Ly6C⁺Ly6G^-CD4⁺ T cells for 84 h. RAW264.7 macrophages were stimulated with E.coli and K.pneumoniae (MOI = 10) for 30 min, respectively, the bacterial content in macrophages were analyzed. With the same treatment in (A), F the ability of macrophages to produce ROS, and G the content of dsDNA in the cell supernatant were detected. H, I Representative gating strategies of 7-AAD⁺ cells and the quantification of 7-AAD⁺ cells. J, K The ability of macrophages to produce ROS detected by flow cytometry, and L, M the content of dsDNA in the cell supernatant of macrophages treated as (D) and (E).