Differences in cytokine production by peripheral blood mononuclear cells (PBMC) between patients with atopic dermatitis and bronchial asthma

It is widely accepted that type 2 helper T (Th2) lymphocytes play a crucial role in the pathogenesis of atopic dermatitis (AD) as well as bronchial as thma (BA). We measured the amounts of IL-5 and interferon-gamma (IFN-gamma) produced by PBMC upon stimulation with house dust mite (HDM) or Candida al bicans (CA) in 17 children (3-15 years) with AD, and compared these values with those of 16 children with BA. Although IL-5 production by PBMC upon st imulation with HDM in patients with AD was significantly higher than that i n 13 non-atopic controls (geometric mean = 23.4 pg/ml versus 5.9 pg/ml, P < 0.05), it was significantly lower than that in patients with BA (177.8 pg/ ml, P < 0.001). The amount of IL-5 produced by PBMC upon stimulation with C A was also significantly lower in patients with AD than in those with BA (7 .2 pg/ml versus 100.0 pg/ml, P < 0.001). The production of IFN-gamma by PBM C stimulated with HDM or CA was also significantly lower in patients with A D than in those with BA (HDM 4.3 pg/ml versus 12.6 pg/ml, P < 0.05; CA 6.5 pg/ml versus 60.3 pg/ml, P < 0.001). Consequently the ratio of IL-5 to IFN- gamma production was high not only in patients with BA but also in those wi th AD. These findings suggest that there are some differences in the regula tion of in Live cytokine production between patients with AD and those with BA, although a Th2-dominant profile is common to both.