Figure 5
From: Lung epithelial cells are essential effectors of inducible resistance to pneumonia
Pam2-ODN (oligonucleotide) induces antimicrobial responses from isolated epithelial cells. (a) Wild-type mice were inhalationally challenged with Pseudomonas aeruginosa grown to mid-log phase with or without aerosolized Pam2-ODN treatment 24 h before infection. Lungs were harvested at the indicated times after infection, homogenized in 1 ml phosphate-buffered saline (PBS), and submitted to serial dilution culture. All sham-treated mice died before the 48-h harvest. (N=3–6 mice/group). (b) Primary mouse tracheal epithelial cell cultures were inoculated with luminescent Streptococcus pneumoniae 4 h after pretreatment with Pam2-ODN or PBS, then the culture pathogen burden was assessed by luminescence intensity. (c) Pathogen burden of HBEC3-KT cultures infected with luminescent S. pneumoniae 4 h after pretreatment with Pam2-ODN or PBS. (d) Heat map of differentially expressed genes in MLE-15 (mouse lung epithelial cells) cells or whole mouse lung homogenates 4 h after treatment with Pam2-ODN, shown as standardized log ratios of fold change. (e) Serum amyloid A3 (Saa3) mRNA levels in whole lung homogenates (upper panel) and SAA3 protein concentration in bronchoalveolar lavage (BAL) fluid (lower panel). (f) Reactive oxygen species generation by MLE-15 cells following treatment with PBS or Pam2-ODN, detected by H2DCF-DA (2′,7′-dichlorodihydrofluoresceindiacetate acetyl ester). (g) Reactive oxygen species generation by intact lungs, assessed by luminescence detection of BAL fluid following lavage with L-012-containing PBS. (hpi, hours post-infection; ND, none detected; *P<0.04 vs. PBS-treated; **P<0.008 vs. PBS-treated; †P<0.008 vs. Pam2-treated; ‡P<0.001 vs. P. aeruginosa-infected; #P<0.035 vs. Pam2-ODN-treated, uninfected). AU, arbitrary units; CFU, colony-forming units; RLU, relative light units.
