Fig. 9: Imaris quantification of green fluorescence following tubular microperfusion with pHrodo Green E. coli BioParticles demonstrates increased uptake and acidification by ICs over time.
From: Kidney intercalated cells are phagocytic and acidify internalized uropathogenic Escherichia coli
a Tubules of “IC reporter” mice with red ICs along with Imaris segmentation profiles are presented for control (top panel) and pHrodo Green E. coli BioParticle perfused tubules (middle and bottom panels). Segmentation cartoons (right panels) are not to scale. (b) Because pHrodo Green BioParticles fluoresce green when internalized and acidified in phagolysosomes, we compared the mean change in green fluorescent intensity for the IC component of each tubule over time. The change in green fluorescence from baseline over time increased significantly for both coated E. coli-exposed bioparticle tubule 1 (BT1) and bioparticle tubule 2 (BT2) compared to the control tubule (CT). Linear regression was used to compare tubules and cells, and the results are presented as the mean ± 95% confidence interval. For BT1, BT2, and CT, respectively, the R2 was 0.28, 0.12, and 0.04, the slope was 60.9, 74.8, and 6.8, the DFn was 1467, 1264, and 17264, the F was 66.5, 104.6, and 217.5, and the Sy.x was 329.8, 244.8, and 56.5. The slopes of BT1 and BT2 were both significantly higher than the slope of CT (P < 10E−15), but not different from each other (P = 0.221). c Within the bioparticle-perfused tubules, 12 of 16 tdT+ ICs had a slope that increased significantly compared to a zero-slope line. Thus, there is some heterogeneity in IC phagocytic capabilities. During linear regression, Graphpad Prism compares slopes by calculating a two-tailed p value to test the null hypothesis that the slopes are identical. For the tubule analysis (b), slopes were compared to one other tubule (BT1 vs. BT2, BT1 vs. CT, and BT2 vs. CT). For the cell analysis (c), the slope of each cell was compared individually to a zero-slope line. Multiple comparisons were not used. Analysis included 2 bioparticle tubules (one with 11 ICs and the other with 5 ICs) and 1 control tubule (with 5 ICs) from one mouse each. Source data are provided as a Source Data File.
