Fig. 5

Differential DNA methylation of SPDEF and FOXA2 in the PBECs from COPD patients and control subjects. PBECs from control 7–17 and COPD 6–16 (Table 1) were differentiated at ALI for 14 days, and DNA methylation of a SPDEF and b FOXA2 was analyzed by pyrosequencing. Data represent the connected median methylation levels (min to max) of different CpG sites in controls or in COPD, and differential methylated CpG sites between COPD-derived cultures and control-derived cultures are shown. Significance was tested by the Mann-Whitney U test. Medians are indicated. ns not significant. *p < 0.05; **p < 0.01