STUDY OF RELEASE OF EOSINOPHIL CATIONIC PROTEINS (ECP AND EPX) IN THEHYPEREOSINOPHILIC SYNDROME (HES) AND OTHER HYPEREOSINOPHILIC CONDITIONS

Background. Up to date, the etiology and the pathogenesis of HES are s till unknown and particularly it is unclear why eosinophils in HES are more aggressive towards tissues than in other eosinophilic conditions . Methods. We assessed the cationic proteins ECP and EPX serum concent rations, their in vitro release from polymorphonuclear cell culture, a nd the monoclonal antibodies EG1 and EG2 in 3 patients with HES, 6 pat ients with other hypereosinophilic conditions and 20 healthy control s ubjects, Results. Serum ECP and EPX concentrations were higher in eosi nophilic patients than in healthy subjects. Hypereosinophilic patients had more EG2+ cells than healthy subjects, but EG2+ rate failed to di fferentiate HES from other hypereosinophilic conditions (p = 0.074). M oreover, the release in vitro of ECP and EPX was significantly higher in HES patients (p < 0.05), Conclusions. Our preliminary results seem to suggest the importance of functional data, such as ECP and EPX rele ase, in differentiating HES from other hypereosinophilic diseases, Par ticularly, ECP and EPX release in vitro is higher in cell cultures fro m HES patients than from patients with other hypereosinophilic conditi ons.