Expression of activation markers and cytokine mRNA by peripheral blood CD4 and CD8 T cells in atopic and nonatopic childhood asthma: effect of inhaled glucocorticoid therapy.

Hypothesis: Activated CD8 as well as CD4 T cells contribute to the production of asthma-relevant cytokines in both atopic and nonatopic childhood asthma.

Objectives: To measure the percentages of peripheral blood CD4 and CD8 T cells expressing naïve/memory (CD45RA/CD45RO) and activation (HLA-DR, CD25) markers, as well as mRNA-encoding interleukin-4 (IL-4) and interleukin-5 (IL-5) in atopic and nonatopic childhood asthmatics and in nonasthmatic controls matched for age and atopic status; and to study the effects of inhaled glucocorticoid therapy of the asthmatics on these measurements.

Methods: Peripheral blood mononuclear cells were isolated from 17 atopic and 8 nonatopic stable (not acutely ill) asthmatics aged 7 to 16 years with moderate-to-severe disease and from 15 nonasthmatic controls matched for age and atopic status.