Figure 4

Arginase-1 expression in the small airway wall of (a) NC compared to (b) COPD-CS. A significant increase in Arginase-1 expression was observed in both (c) epithelium and (d) sub-epithelium. Data are presented as median and range; group comparisons with Mann-Whitney two-tailed t-test; p < 0.05 was considered significant.