Expression of HIF-1α in pediatric asthmatic patients.

Background: Several studies have suggested that HIF-1α regulates eosinophil activity and induces epithelial inflammation via NF-κB activation in the pathophysiology of asthma. The purpose of this study was to examine the expression of the transcription factors HIF-1α and nuclear HIF in mononuclear cells obtained from peripheral blood samples of healthy pediatric patients, asthmatic patients, and asthmatic exacerbations, regardless of disease severity.

Methods: HIF-1 levels were measured using immunocytochemistry in 133 patients aged 6 to 17 years in this crosssectional and comparative study. A microscope was used to examine glass slides, and positive cells were counted in four fields per slide using an image analyzer.

Results: HIF-1α and nuclear HIF levels were significantly higher in asthma patients and even higher in patients experiencing asthma attacks (p<0.0001, 95% CI). There was no significant difference in the percentage of HIF-1α expression between groups with intermittent asthma and those with mild persistent asthma, nor between patients with asthma and those experiencing asthma exacerbations.

Conclusions: When compared to healthy individuals, the expression of nuclear HIF and HIF-1α is increased in peripheral mononuclear cells in asthma patients and even more so in asthma exacerbations. This suggests that HIF-1α is important in the pathogenesis of this disease.