Fig. 6

TLR4 overexpression promotes endosome maturation. a The endosomal pH values of transgenic (TG) and wild-type (WT) monocytes were assessed following infection with pHrodo- labelled E. coli (MOI = 10). Fluorescence values were read at intervals using an emission wavelength of 590 nm. Each sample had its own standard curves. The values were compared with standard curves obtained using corresponding sheep monocytes treated for 30 min at a fixed pH (4.21, 5.18, 6.2, 7.38, or 8.16) in phosphate-buffered saline containing 1% Triton X-100. The start of the experiment (0 min) was when the bacteria were first added. b Effects of inhibitor treatment (2 μmol/L TAK242, 3 μmol/L dasatinib, and 3 μmol/L filipin) on the endosomal pH of the TG and WT monocytes. Dimethyl sulfoxide (DMSO) was used as the control. c Fluorescence images of FITC- labelled E. coli colocalization with the primary endosomal marker EEA1 in the TG and WT monocytes after 30 min of infection. Scale bar: 10 μm. d Fluorescence images of FITC- labelled E. coli colocalization with the lysosomal marker LAMP1 in the TG and WT monocytes after 30 min of infection. Scale bar:10 μm. All data are presented as the mean ± SD, n ≥ 3; *P < 0.05, **P < 0.01. DAPI, cell nuclei stain