Human eosinophils and parasitic diseases — III. β-interferon increases eosinophil IgG-Fc receptor expression and capacity

Eosinophilic granulocytes from the blood of patients with parasitic diseases were preincubated in the presence or absence of β-interferon (β-IFN). The number of cells bearing IgG-Fc receptors was determined by rosette formation with chicken erythrocytes coated with IgG antibodies. β-IFN augmented the expression of IgG-Fc receptors on the cells within 1 h incubation. Treatment of β-IFN with heat or acid did not abolish the activity. The doses of β-IFN needed to induce the modulations of IgG-Fc receptors could also augment the eosinophil-mediated antibody-dependent cytotoxicity (ADCC) against chicken red blood cells which resulted most pronounced when the IgG antibodies were present in suboptimal amount. These data suggest the role of β-IFN in the host resistance to parasitic diseases, mainly in the initial phases of parasitic infestation when the specific IgG antibody levels are very low.