FIGURE 1.
CFTRinh-172-induced inhibition of phagosomal acidification in AMs isolated from WT mice. A, fluorescein-conjugated zymosan was exposed to WT AMs in the absence (control) of inhibitor or to cells that had been pretreated with 10 μm CFTRinh-172 for 30 min. Images were collected on a Leica SP2 AOBS laser confocal microscope (see supplemental material). Particles not ingested by the cells are marked with white arrows. DIC, differential interference contrast. B, calibration curve was performed on the same cells using a three-component buffer with ionophores. Data were analyzed using ImageJ software. Single zymosan particles found in focal plane were taken as ROIs and represent data points on the curve. Data are expressed as means ± S.E. Calibration curve was fitted using Origin and the dose-response model. C, ratio of green fluorescence between particles inside versus outside cells (white arrows in A) in control cells (upper panel) and in the presence of 10 μm CFTRinh-172 (lower panel). For analysis, fluorescence intensity of each inside particle was divided by the mean intensity of all outside particles. Asterisk indicates significance. Bars represent the mean of these ratios ± S.E.