Fig 1: Mechanism of S100A9 Effect on Macrophages(A) Left: proliferation of OT-1 splenocytes in the presence of specific peptides in the presence of CD11b+Gr-1+ myeloid cells from BM of WT or S100A9 Tg tumor-free mice. Right: IFN-? ELISpot. Experiments were performed in triplicate and repeated twice. Mean and SD are shown.(B) T cell proliferation of OT-1 splenocytes in the presence of specific peptides and Mon-derived macrophages from WT or S100A9 Tg tumor-free mice. Dotted line indicates cell proliferation in the absence of macrophages. Experiments were performed in triplicate. Results of individual mice (n = 3–5) and mean and SD are shown. p values were calculated in two-sided Student’s t test.(C) Indicated gene expression in WT or S100A9 Tg Mon-derived macrophages. Expression was normalized togadph. Results of individual mice (n = 3) and mean and SD are shown. p values were calculated in two-sided Student’s t test.(D) Relative expression of cebpb in WT or S100A9 Tg TAMs isolated from LLC TB mice.(E) Expression of C/EBPß-targeted genes in WT, S100A9Tg, and S100AKO TAMs isolated from LLC TB mice. Expression was normalized to gadph. Results of individual mice (n = 3–5) and mean and SD are shown. p values were calculated in two-sided Student’s t test.(F) Expression of C/EBP-ß-targeted genes in BMDMs or TR macrophages isolated from lung tissue of EL4 TB mice. Expression was normalized to actb. Results of individual mice (n = 4) and mean and SD are shown. p values were calculated in two-sided Student’s t test.(G) Expression of Arg-1 in control siRNA or C/EBP-ß siRNA S100A9 Tg Mon-derived macrophages. n = 4.(H) Proliferation of OT-1 splenocytes in response to specific peptides in the presence of Mon-derived macrophages treated with control siRNA or C/EBP-ß siRNA. n = 5. Dotted line indicates cell proliferation in the absence of macrophages. Mean and SD are shown. p values were calculated in two-sided Student’s t test.