A STUDY ON RIL-4 AND IFN-GAMMA REGULATING IGE SYNTHESIS IN BRONCHIAL-ASTHMA PATIENTS

Objective To investigate the cytokines responsible for pathophysiology of asthma. Methods In vitro effects of recombinant interleukin-4 (rIL -4) and interferon-gamma (IFN-T) on synthesis of immunoglobulin E (IgE ) by peripheral blood mononuclear cells (PBMC) were studied in 30 asth matic patients and 25 normal controls. Results Spontaneous IgE synthes is by PBMC significantly increased in patients with asthma compared wi th the controls (t =4.471, P<0.001). Although the maximun amounts of I gE synthesis using PBMC after stimulation with rIL-4 were almost the s ame in the patients with asthma and in the controls (P>0.05), the enha ncement rate of rIL-4-induced IgE synthesis was lower in the asthma pa tients than in the controls (t= 4.6719, P < 0.005). IFN-gamma suppress ed both spontaneous and rIL-4-induced IgE synthesis by PBMC in the ast hma patients. The suppressive effect on IgE synthesis was more promine nt in the patients with asthma than in the controls (i=7. 1833, P<0.01 1). Conclusions Asthma attacks are related to IgE-dependant trigger me chanism. The imbalance of IL-4 and IFN-gamma in vivo is the cause of e levated IgE that can produce mediators release and asthma attacks. IFN -gamma can inhibit IgE synthesis, so IFN-gamma may he a new approach t o the treatment of asthma.