In the epidemiological study there was suggested that respiratory tract infections--were a strong risk factors for the beginning and development of bronchial asthma. The aim of the study was the evaluation of intracellular cytokine IL-4 and IFN-gamma on peripheral blood T subsets in children with atopic asthma (AA) and recurrent respiratory tract infection with bronchospasm (RRTI).
Method: Peripheral blood T cells were stained with fluorescence-labelled antibodies specific for intracellular cytokines IFN-gamma and IL-4 and cell surface markers CD3, CD4 and CD8, and were subjected to flow-cytometric analysis.
Results: Comparing peripheral blood lymphocytes of atopic asthma patients with those of recurrent infections we found significantly more cells positive for IL-4 in asthma patients than in recurrent infection patients, both in the CD3+ subsets (p<0.03) and CD4+ subset (p<0.01). We have also found that percentage of CD4+ was significantly lower (p<0.007) and percentage of CD8+ cells was significantly higher (p<0.05) in RRTI group comparing to atopic asthma patients. In AA group there was a significant increase intracellular expression of IL-4 among the CD3+ (p<0.03) and CD4+ (p<0.01) subsets and no significant differences among CD8+ subset. In AA group there was a significant decrease ratio of IFN-gamma/IL-4 among all of the evaluated subsets.
Conclusion: Basing oneself on these results we conclude that markers of atopy are: increased intracellular expression of IL-4 among CD4+ cells and decreased IFN-gamma.