Figure 5.

Comparison of Toll-like receptor (TLR) signaling pathway expression in infant and adult airway epithelial cell cultures. (A and B) Relative gene expression of selected TLR signaling pathway molecules in infant and adult cultures. Data are expressed as 2^ (− average delta threshold cycle (Ct) value) where delta Ct = Ct value of gene of interest − mean Ct value of housekeeping genes. Columns represent the mean ± SE of 8–9 animals per age group. Open columns represent infant cultures, whereas solid columns represent adult cultures. *P < 0.05, according to t test. (C–J) Cryosections from representative adult (C, D, G, and H) and infant (E, F, I, and J) tracheas were stained with FITC-conjugated anti-human IL-1α antibody (D and F) or anti-human peptidoglycan recognition protein PGLYRP2 with an Alexa488-conjugated secondary antibody (H and J). FITC-conjugated and unconjugated mouse IgG1 isotype controls are included for comparison (C, E, G, and I). Images were collected at ×40 magnification. Scale bar, 20 μm.