Figure 6

Simultaneous multiparameter physiological measurements of (a) oxygen consumption, (b) extra-cellular acidification and (c) mitochondrial membrane potential (MMP). For clarity, the data obtained from the same cell population are color-coded with the same color across all three graphs. While oxygen consumption kinetics are predominantly linear until all oxygen is consumed (inflection point in the kinetics), pH and MMP kinetics are highly variable and non-linear. After an initial decrease, the pH kinetics of some of the populations (pink, purple, and brown curves) showed an increase in pH value, while the remaining populations exhibited decreasing pH for the entire duration of the assay. The MMP kinetics differed strongly among the populations, with some maintaining or even slightly increasing the MMP levels (red and blue curves, correspondingly). The population (cluster) sizes are as follows: red −51, blue −46, beige −40, purple −42, pink −38, brown −39 cells. Note: the brown curve in oxygen consumption kinetics (panel a) is invisible due to a strong overlap with the pink and purple curves.