Pharmacological induction of autophagy increases bacterial colocalization with autophagy factors. (A, B) THP1 cells infected with B. cenocepacia at MOI 1 for 4 h either without (upper panels) or with 50 μg/mL rapamycin pretreatment (lower panels). Imaging of nuclei (blue), bacteria (green), and autophagy effectors (red) is shown for (A) Ubiquitin and (B) LC3B, respectively. Merge and zoomed panels show only the nuclear outline. Arrows highlight examples of bacteria/autophagy effector colocalization. (C) Quantification of percent bacterial colocalization with autophagy effectors after a 6 h infection with and without rapamycin pretreatment. (D) Confocal imaging of bacteria (red) and LC3B-GFP (green) in THP1 cells infected with B. cenocepacia at MOI 1 for 6 h. Scale bars = 50 μm. Data shown are representative images (A, B, and D) or combined measurements (C; mean + SEM) from three independent experiments. *P < 0.05, **P < 0.01 (two-tailed t-test).