You are here:
ERK1/2 and p38 regulate inter-individual variability in ozone-mediated IL-8 gene expression in primary human bronchial epithelial cells
Citation:
Bowers, E., S. McCullough, D. Morgan, L. Dailey, AND D. Diaz-Sanchez. ERK1/2 and p38 regulate inter-individual variability in ozone-mediated IL-8 gene expression in primary human bronchial epithelial cells. Scientific Reports. Nature Publishing Group, London, Uk, 8(1):9398, (2018). https://doi.org/10.1038/s41598-018-27662-0
Impact/Purpose:
IL-8, a potent chemokine, is elevated in the airways following ozone exposure, but its abundance exhibits inter-individual variability, implying that the differential regulation of this gene could be an important factor underlying ozone inflammatory response variability. Here we show that an important source of IL-8 variability may be differences in transcriptional responses in airway epithelial cells. Our data suggest that the magnitude of IL-8 induction may be due to the intrinsic properties of these cells.
Description:
Inter-individual variability is observed in all biological responses; however this variability is difficult to model and its underlying mechanisms are often poorly understood. This issue currently impedes understanding the health effects of the air pollutant ozone. Ozone produces pulmonary inflammation that is highly variable between individuals; but reproducible within a single individual, indicating undefined susceptibility factors. Studying inter-individual variability is difficult with common experimental models, thus we used primary human bronchial epithelial cells (phBECs) collected from many different donors. These cells were cultured, exposed to ozone, and the gene expression of the pro-inflammatory cytokine IL-8 was measured. Similar to in vivo observations, we found that ozone-mediated IL-8 expression was variable between donors, but reproducible within a given donor. Recent evidence suggests that the MAP kinases ERK1/2 and p38 mediate ozone-induced IL-8 transcription, thus we hypothesized that differences in their activation may control IL-8 inter-individual variability. We observed a significant correlation between ERK1/2 phosphorylation and IL-8 expression, suggesting that ERK1/2 modulates the ozone-mediated IL-8 response; however, we found that simultaneous inhibition of both kinases was required to achieve the greatest IL-8 inhibition. We proposed a “dimmer switch” model to explain how the coordinate activity of these kinases regulate differential IL-8 induction.
URLs/Downloads:
DOI: ERK1/2 and p38 regulate inter-individual variability in ozone-mediated IL-8 gene expression in primary human bronchial epithelial cells