Figure 4

sMICB skews macrophages into alternative activated phenotype through NKG2D and activation of STAT3. B6 mice bone marrow cells were cultured in the presence of L929 conditioned media (CM-L929) for 3 days and cultured continually with or without sMICB in combination with NKG2D blocking antibody CX5 or STAT3 inhibitor AG490 for additional 3 days before harvest. Cells were stained with anti-CD206, anti-CD11c, and anti-F4/80 in combination with intracellular Arginase I staining. (a) Schema of bone marrow (BM) culture condition. (b, c, d) Representative histogram and summary data showing that sMIC increases the expression of F4/80 (b), CD206 in gated F4/80⁺ cells (c), and arginase I (arg I) in CD206⁺ cells (d). Data also show that blocking NKG2D or STAT3 mitigates the effect of sMICB. (e) Intracellular levels of pSTAT3 in BM-derived macrophages at various time points post-exposure to sMICB. Three replicates were performed in each experiment. Data represent five independent experiments. *P < 0.05.