Eosinophil Chemiluminescence Response to Cytokines and Opsonized Zymosans in Atopic Dermatitis

Chemiluminescence (CL) responsiveness of eosinophils (Eos) to zymosan particles coated with either IgG, C3 or both and eosinophilopoiesis-modulating cytokines was investigated in patients with atopic dermatitis (AD), and an attempt was made to correlate these CL responses with serum levels of eosinophil cationic protein (ECP) which increased in response to the extent of AD severity, but not blood eosinophil counts. A high degree of positive correlation existed between serum levels of ECP and either IgG containing opsonized zymosan- or interleukin-5 (IL-5)-induced CLs. The CL values induced by these two stimuli appeared to be directly correlated with the intensity of each ligand-linked receptor expression. These results suggested that Fc gamma RII-and/or IL-5R-mediated eosinophil activation at the site of lesional skins might implicate in deterioration of cutaneous inflammation, and consequently cause an elevation of serum levels of ECP in AD.