SNAP29 relocation to <i>E. coli</i> phagosomes in infected mast cells is transient.

<p>(A) RBL-2H3 cells were infected with <i>E. coli</i> expressing mCherry (red) for 0 h, 1 h, 2.5 h or 4 h. Cells were then fixed, permeabilized and labeled with anti-SNAP29/anti-rabbit AlexaFluor488 Abs (green). The nucleus was labeled with Hoechst (blue). SNAP29 localization was assessed using confocal microscopy. SNAP29 staining accumulates around <i>E. coli</i> phagosomes at t = 1 h and t = 2.5 h. The <i>inset</i> in each image shows an enlarged area of <i>E. coli</i> phagosomes. This experiment is representative of n = 3. Scale bars = 20 µm. (B and C) RBL-2H3 cells were infected with <i>E. coli</i> mCherry (red) for 2.5 h (B) or 4 h (C). Cells were fixed and stained as described in <i>A</i>. SNAP29 localization was assessed using confocal microscopy. Two different <i>E. coli</i> phagosomes are shown on the left and right of the center image. Z-sections of 0.3 µm were used to reconstruct each phagosome in 3D (shown below the enlarged phagosomes). SNAP29-positive endosomes associate with phagosomes at 2.5 h, but are not present 4 h post-infection. Scale bars = 20 µm.