1157 Ozone as an aggravating factor in atopic eczema

The effect of environmental pollutants on atopic eczema (AE) is controversial with different proposed mechanisms in skin including oxidative stress, the aryl hydrocarbon/artemin pathway (AhR/ARTN), and JAK/STAT pathway. Mathematical modelling a cohort AE patients Bangladeshi ancestry commonly studied meteorological variables showed that long-term exposure to ground-level Ozone (O3) has strongest association severity. Ground level O3 generated by combination sunlight volatile organic compounds nitrogen oxides. aim study was evaluate low levels keratinocytes 2D cultures Western blotting RNA sequencing. Sub-confluent telomerase-immortalized human were exposed 70-80 ppb for 1 hour closed chamber 5 days/week over period 3 weeks. Cells split, regrown harvested protein extraction day 7 weekly. Control cells pure air (O3: 5-7 ppb) similar chamber, under culture conditions. ROS production assessed 2’,7’- dichlorofluorescin diacetate assay. RNA-seq analysis performed using DESEQ2 R package Partek Flow software. (n=3) increased expression phospho-STAT3 AhR starting from 2nd week O3. also generation. A total 20 genes significantly changed (17 up-regulated down-regulated) at false discovery rate < 0.05, fold change ≥ 1.25 or ≤ -1.25. Pathway enrichment CLEC7A/inflammasome be affected as well IL10/IL4/IL13 signaling STAT3 signaling. We suggest chronic very concentrations may pathomechanism increasing stress inflammation skin.