Fig. 7: Eructophagy is preceded by blebs on the phagolysosomal membrane.

a Representative sequential images of BMMØs following the phagocytosis of experimental particles bearing the quenched DQ Green BSA substrate (green), the pH indicator pHrodoSE (red) and the reference fluorophore AF647SE (magenta). Phagolysosomal morphology can be visualized in the green channel as the soluble DQ Green BSA peptide products are not particle-restricted and hence occupy the entire phagolysosomal lumen. Arrow shows a ~0.5 μm diameter bleb of the phagolysosomal membrane commonly observed before an eructophagic event (observed as the sudden loss of soluble DQ Green BSA peptide products to the extracellular space). Images were captured using a Leica SP5 confocal microscope between 1 and 3 h post-phagocytosis at 37 °C. b Quantification of the number of blebs per phagolysosomes following the phagocytosis of experimental particles bearing the self-quenched DQ Red BSA (red) and the reference fluorophore AF647SE (magenta). N = 15; 5 fields of view (FOV) over three biologically independent experiments. Error bars presented as means ± SEM. *P ≤ 0.05 by one-way ANOVA with Bonferroni’s post hoc test. Source data are provided as a Source Data file.