Figure 1
From: Lung epithelial cells are essential effectors of inducible resistance to pneumonia
No leukocytes are identified to be required for Pam2-ODN-induced resistance. (a) Wild-type C57BL/6 J mice were depleted of neutrophils by intraperitoneal injection of anti-Ly6G Ab, then inhalationally challenged with Pseudomonas aeruginosa grown to mid-log phase following a single aerosolized treatment consisting of Pam2CSK4 and oligonucleotide (ODN) M362 (Pam2-ODN) or phosphate-buffered saline (PBS; sham) treatment of the mice 24 h before the infectious challenge. (b) Neutrophil-depleted mice were inhalationally challenged with Streptococcus pneumoniae in mid-log phase with or without aerosolized Pam2-ODN pretreatment 24 h before infection. (c) Wild-type mice were depleted of alveolar macrophages by two intratracheal treatments with liposomal clodronate before challenge with P. aeruginosa with or without aerosolized Pam2-ODN pretreatment 24 h before infection. (d) Rag1−/− mice were challenged with P. aeruginosa with or without aerosolized Pam2-ODN pretreatment 24 h before infection. (e) Mice expressing the diphtheria toxin receptor under the CD11c promoter received repetitive intratracheal doses of diphtheria toxin before challenge with P. aeruginosa with or without aerosolized Pam2-ODN pretreatment 24 h before infection. (f) Wild-type mice were depleted of plasmacytoid dendritic cells by intraperitoneal injection with anti-PDCA Ab before challenge with P. aeruginosa with or without aerosolized Pam2-ODN pretreatment 24 h before infection. (g) Wild-type mice were depleted of natural killer cells by intraperitoneal injection with anti-NK1.1 Ab before challenge with P. aeruginosa with or without aerosolized Pam2-ODN pretreatment 24 h before infection. (h) Perf1−/− mice were challenged with P. aeruginosa with or without aerosolized Pam2-ODN pretreatment 24 h before infection. For all the experiments, the left panel displays pneumonia survival (N=8–10 mice/group for all the experiments), the right panel displays the lung pathogen burden immediately after the infectious challenge as assessed by serial dilution culture of whole lung homogenates (N=3–6 mice/group for all the experiments). Panels shown are representative of at least three separate experiments. All the survival groups were followed for at least 14 days, no deaths occurred outside the presented periods. (*P<0.03, **P<0.005, †P<0.0006, ‡P<0.00001 relative to PBS-treated control). CFU, colony-forming units.
