Fig. 2.

Methylation of histone lysine residues in asthmatic and healthy airways. Airway sections from asthmatic and healthy patients were formalin fixed, paraffin embedded and then sectioned for immunohistochemical analysis. Sections were stained for methylation of H3K4me2 (a, b), H3K4me3 (c, d), H3K9me3 (e, f), H3K27me3 (g, h), and H3K36me3 (i, j). Scale bar is equal to 50 μm. The expression of and the % of positive nuclei stained for H3K9me3 within the epithelium was quantified for both healthy (H, white bar) and asthmatic (A, blue bar) subjects (k, l). Data are expressed as % of positive area of airway epithelium ± SEM (n = 6) and % positive nuclei ± SEM (n = 6). A two-tailed unpaired t-test was performed, *indicates p < 0.05, **indicates p < 0.01