Fig. 4. Altered tumor immunoediting in obese hosts.

B16 melanoma tumor cells were grown and harvested from cell culture. A Baseline expression of intracellular Gp100, surface MHC-I, and surface MHC-II was assessed via flow cytometry. MHC-I and MHC-II expression was also analyzed after 24-h in vitro stimulation with recombinant murine IFNγ. Subcutaneous B16 tumors were harvested on day 14 and tumor cells were assessed for expression of intracellular Gp100 by flow cytometry. B Representative FACS plots show Gp100 expression by B16 cells from mice on normal chow (NC; blue) and western diet (WD; red), and pooled median fluorescence intensity (MFI) data from 2 independent experiments is graphed (NC n = 15, WD n = 9). C Representative FACS plot and pooled MFI data from 2 independent experiments is graphed showing MHC-I (NC n = 10, WD n = 9), MHC-II (NC n = 15, WD n = 9), and IFNγ receptor (IFNγR) (NC n = 10, WD n = 9) expression on Gp100⁺ tumor cells. D Bi-lateral subcutaneous B16 and YummG melanoma tumors were established in lean B6 and OT-II mice. Tumors were harvested on day 14 and expression of Gp100 and MHC-I/II was measured by flow cytometry (All groups n = 12 mice). E Graphs display pooled data from 2 independent experiments. For all bar graphs, each point represents an individual mouse with SEM indicated by the error bars. All box-and-whisker plots: The box indicates the 25^th and 75^th percentile, the line indicates the data median, and the whiskers indicate the minimum and maximum of all individual values. All n’s represent an individual mouse. Exact P values were calculated by two-sided Mann–Whitney U test.