Figure 5.

The Lc3-mediated response in neutrophils occurs to both live and heat-killed S. aureus, but spacious Lc3-positive vesicles are formed only with live bacteria. (A and B) Confocal photomicrographs are shown as maximum intensity projections of the Lc3-mediated response at 1 hpi in live lyz:RFP-GFP-Lc3 embryos infected with approximately 1500 CFU of live (A) or heat-killed (B) mCherry-labeled S. aureus. Scale bars: 10 µm. (C) Quantification of Lc3 associations with intracellular S. aureus at 1 hpi within neutrophils of live lyz:RFP-GFP-Lc3 embryos infected with approximately 1500 CFU of live or heat-killed (HK) mCherry-labeled S. aureus. Data are shown as mean ± standard deviation (SD) obtained from three independent experiments. 80 infected neutrophils in 16 larvae injected with live bacteria were analyzed. 72 infected neutrophils in 16 larvae injected with heat-killed bacteria were analyzed. Unpaired two-tailed t-test was used. ns – not significant. (D) Quantification of neutrophils with spacious S. aureus-containing phagosomes at 1 hpi within live lyz:RFP-GFP-Lc3 embryos infected with approximately 1500 CFU of live or heat-killed (HK) mCherry-labeled S. aureus. Data are shown as mean ± standard deviation (SD) obtained from three independent experiments. 46 infected Lc3-positive neutrophils in 16 larvae injected with live bacteria were analyzed. 44 infected neutrophils Lc3-positive in 16 larvae injected with heat-killed bacteria were analyzed. Unpaired two-tailed t-test was used. **** P < 0.0001