IL-26 protein in the airway lumen, airway leukocytes, and bronchial tissue biopsy samples from smokers and nonsmokers
In this figure, datasets on human samples from one cohort (COSMIC cohort) are presented and all the IL-26 protein concentrations were quantitated in cell-free fluid samples using ELISA. (A) Concentrations of IL-26 in BAL fluid samples from healthy nonsmokers (n=37), smokers without COPD (n=40), and smokers with COPD (n=33). (B) Concentrations of IL-26 in BW fluid from healthy nonsmokers (n=34), smokers without COPD (n=33), and smokers with COPD (n=33). (C) Concentrations of protein in BAL fluid from smokers with or without COPD who have chronic bronchitis (n=18) and those without chronic bronchitis (n=55). (D) Representative pictures (ICF) for cellular IL-26 protein expression in AM from healthy nonsmokers (left panel), smokers without COPD (middle panel), and smokers with COPD (right panel). Each panel shows nuclear staining (blue) in the upper left quadrant, CD68 staining (of AM, red) in the lower left quadrant, IL-26 staining (green) in the upper right quadrant and CD68 and IL-26 co-staining (red and green) in the lower right quadrant. (E) The integrated density (CTCF using ImageJ after the ICF staining) of IL-26 expression in AM, n=8 for all groups. (F) Representative pictures (IHC) for the isotype control (upper left quadrant), IL-26 staining (brown) in healthy nonsmokers (lower left quadrant), IL-26 staining (brown) in smokers without COPD (upper right quadrant), and IL-26 staining (brown) in smokers with COPD (lower right quadrant). (G) The intensity of IL-26 expression in the bronchial tissue biopsies, n=8 for all groups. The horizontal lines in (A–C, E, G) indicate medians and the P-values are according to the Mann–Whitney test. The P-values <0.05 are considered significant. Concentrations of IL-26 on the y-axis (A–C) are represented in log scale.