HIGH-AFFINITY IGE RECEPTOR-MEDIATED PROSTAGLANDIN-E2 PRODUCTION BY MONOCYTES IN ATOPIC-DERMATITIS

High affinity IgE receptor (Fc epsilon R I) expression on monocytes an d its upregulation on monocytes from patients with atopic dermatitis ( AD) have been recently reported. In this study, we investigated whethe r prostaglandin E2 (PGE2) release from AD monocytes was Fc epsilon R I -dependent or not. The monocytes were stimulated with anti-Fc epsilon R I monoclonal antibody (mAb) and anti-Fc epsilon R II mAb. Cross-link ing of Fc epsilon R I, but not that of Fc epsilon R II induced PGE2 re lease from monocytes. In order to confirm that the PGE2 release is IgE -dependent, stimulation with IgE+anti-IgE, IgG+anti-IgG and immune com plexes made by incubation with AD patients' serum and recombinant Derf II (rDerfII-IC) were carried out in the culture. Significant PGE2 rele ase by all the stimulants was observed, as compared with spontaneous r elease. PGE2 release by immune complex made by incubation with IgE-abs orbed AD serum and rDerfII was much lower than that by rDerfII-IC. In monocytes from nonatopic donors, significant PGE2 release was observed when stimulated with IgE+anti-IgE, IgG+anti-IgG, rDerflI-IC, but not with anti-FC epsilon R I mAb and anti-Fc epsilon R II mAb. However, th e release were significantly lower than respective PGE2 releases from AD monocytes. dermatitis . Taken together, cross-linking of Fc epsilon R I and IgE induced a PGE2 release Prostaglandin E2 from monocytes. T his is a first report demonstrating an Fc epsilon R I-dependent