The effect of pollutants on atopic eczema (AE) has been controversial; with different proposed inflammatory mechanisms in skin such as the aryl hydrocarbon (AhR), JAK/STAT pathways, oxidative stress and Carbonylated proteins (CPs). It has been shown that CP levels are higher in dry skin and AE skin lesions. Tower Hamlets Eczema Assessment (THEA) is a clinical environmental study in Bangladeshi AE patients. Ambient exposure of THEA patients to commonly studied pollutants showed that long-term exposure to ground-level Ozone (O3) has the strongest association with eczema severity. We aimed to evaluate CP expression level by western blotting in skin tape strips in patients and controls and correlate it to Filaggrin (FLG) genotype status. 49 AE patients and 10 normal controls of Bangladeshi ancestry were recruited. Buccal swabs were taken for DNA extraction and 9 tapes were harvested from a non-lesional skin site for protein extraction. There was a significant higher CP level in patients with FLG mutations compared to wild type controls/patients (Kruskal Wallis test p=0.03242). The number of FLG mutations correlated positively and significantly with CP expression level (rho (ρ)=0.34, p=0.0095). This suggests that carrying more than one mutation might be associated with more inducible oxidative stress by environmental stimuli such as O3 in AE patients. To study the effect of long-term exposure to low levels of Ozone on keratinocytes; an Ozone exposure chamber was developed. Sub-confluent immortalized human keratinocytes (NTRT) were exposed to 70-80 ppb of O3 for 1 hour; for 5 days/week over a period of 3 weeks. Cells were split, regrown and harvested on day 7 of each week. Control cells were exposed to pure air in an identical chamber, under identical conditions. Preliminary western blotting results of 6 repeats showed increased activation of phospho-STAT3/Total STAT3 and AhR starting from the 2nd week of exposure to O3. This suggests that chronic exposure to very low concentrations of Ozone may be one of the proposed inflammatory mechanisms in AE.

ESDR144 - Carbonylated proteins and Ozone in atopic eczema

The scientific meeting of the European Society for Dermatological Research (ESDR) is held yearly, usually in September. With an international attendance of more than 1000 skin scientists from around the globe, the four-day event includes short oral presentations from peer-reviewed abstracts, keynote lectures from international experts, sponsored symposia, satellite programs, educational events as well as an important focus on posters, networking and building collaborations amongst scientists. For more information about this year’s meeting visit our website.