Population density modeling of redox ratios per cell illustrates heterogeneous macrophage metabolism at A) 24 hours, B) 48 hours, and C) 72 hours of stimulation. Two distinct sub-populations of cell metabolism are present for each time point and stimulation condition. The proportions of the low (p1) and high (p2) redox ratio sub-populations were calculated to represent the contribution of each sub-population to the overall distribution. Cell number per time point (24/48/72 hours) – M0:1008/2153/2263 cells; M(IFN-γ):1289/999/1100 cells; M(IL4/IL13):1443/1821/2157 cells. †,†† p<0.05, 0.01 – low population; *,**p<0.05, 0.01 – high population; red – M0 vs. M(IFN-γ), blue – M0 vs. M(IL4/IL13), black – M(IFN-γ) vs. M(IL4/IL13). D) Expression levels of known M1-like and M2-like macrophage markers (CD86, CD206) were quantified for M0, M(IFN-γ), and M(IL4/IL13) macrophages at 24 hours, 48 hours and 72 hours; ╪╪╪ p<0.001, ^^^^p<0.0001. Expression levels of M1-like and M2-like genetic markers for E) M(IFN-γ), and F) M(IL4/IL13) conditions were evaluated with qPCR at 24 hours, 48 hours, and 72 hours following stimulation.