Abbreviations:
ALI: air-liquid interface,
BEGM: bronchial epithelial growth medium,
DNMT: DNA methyltranferase
FITC: fluorescein isothiocyanate,
HBEC: human bronchial epithelial cells,
LINE-1: long interspersed nuclear element-1
5-mc: 5-methylcytosine
TER: transepithelial electric resistance,
ZO: zonula ocludens
FIGURE LEGENDS :
Figure 1 . Increased global methylation in bronchial epithelial cells in asthma
  1. Global LINE-1 methylation levels in bronchial epithelial cells from healthy control (n=4) and asthma patients (n=3) on the baseline. (B) Representative immunofluorescence staining and data showing the mean intensity of ALI cultures of differentiated bronchial epithelial cells from controls (n=5) and asthma patients (n=8) for 5-methylcytosine (5mc). Data are presented as mean±SD, (**P < 0.01), Mann Whitney U test.
  2. Figure 2. DNA methyltransferase inhibitor decreases global methylation and improve the barrier integrity of bronchial epithelial cells in asthma
Representative immunofluorescence staining of 5-methylcytosine (5mc) and data showing the mean intensity in asthmatic ALI cultures of HBEC treated with 8 µM DNA methyltransferase inhibiitor, SGI-1027 for 48 hours, (n=8). (B) Increased TER in ALI cultures of HBEC from asthmatic individuals treated with 8 µM of DNA methyltransferase inhibitor-SGI-1027, n=5 per group. (C) The decreased paracellular flux of 4kDa FITC-dextran in response to 48 hours treatment of 8 µM DNA methyltransferase inhibitor SGI-1027, n=5 per group. (D) Western blots of DNMT1, ZO-1 and claudin-18 from ALI cultures of asthmatic HBEC treated with DNA methyltransferase inhibitor-SGI-1027 in diferent doses (2 µM, 4 µM, 8 µM, 16 µM), n=5. Data represent mean±SD, (*P < 0.05), (**P < 0.01), Mann Whitney U test.
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