The studies of T-regulatory (Treg) cells in the pediatric allergic disorders, especially allergic rhinitis (AR), are very few and
still far from being elucidated. The aim of this study is to assess the frequencies of CD4+CD25+Foxp3+ (CD4+Tregs) and
CD8+CD25+highFoxp3+ (CD8+Tregs) regulatory T lymphocytes in the peripheral blood of children with AR. In fresh whole
blood of 60 children with AR and 40 healthy controls, the frequencies of CD4+Tregs and CD8+Tregs were examined by
flow cytometry. The total IgE concentration in the serum was measured. In AR children, the frequencies of CD4+Tregs and
CD8+Tregs were significantly reduced when compared to control group (p=0.041, p=0.011, respectively). Moreover, the
expressions of Foxp3+ in CD4+CD25+high and CD8+CD25+high cells were significantly lower in patient group than controls.
We found a significant negative correlation between the frequencies of CD4+Tregs and the total IgE concentration (p<0.01).
In conclusion, the present study demonstrated that the percentages of CD8+Tregs and CD4+Tregs T cells were significantly
decreased in children with AR. This suggests that decreased Treg cells might represent a defect in the compartment of T-cell
population in children with AR. Further studies are warranted to fully appreciate the clinical relevance of Tregs in children
with AR.