Fig. 2.

B7-H4 KO mice display enhanced anti-tumor T cell responses relative to WT mice. After 5 weeks, a tumor cells and b splenocytes from WT or B7-H4 KO mice were harvested, stained and analyzed via flow cytometry for CD4+ and CD8+ T cells, gated on live, CD45+ cells. c Percentage of tumor cells positive for MHC I, MHC II and B7-H1, gated on live, CD45- cells. d Mean fluorescence intensity of MHC I and MHC II on tumor cells. e mRNA was extracted from WT and KO tumors, and qPCR was performed to quantitate the abundance of IFN-γ transcripts in the tumor microenvironment. f Percentage of CD11b+Gr-1+MDSCs gated over total CD45+cells from tumor and spleen. g Ex vivo myeloid-derived suppressor cells were isolated from splenocytes of WT and B7-H4 KO tumor-bearing mice, and co-cultured with CD3 and CD28-stimulated naïve splenocytes. Thymidine incorporation assay was performed to measure T cell proliferation and MDSC suppression after 2 days. Data presented as mean ± standard error. The presented data were either pooled from two to three experiments, or represent two or more independent experiments with similar results. *P < 0.05; **P < 0.01; ***P < 0.001