SEASONAL ENHANCEMENT OF IL-4 INDUCED IGE SYNTHESIS BY PERIPHERAL-BLOOD MONONUCLEAR-CELLS OF ATOPIC PATIENTS

The role of IL-4 on IgE synthesis has been well established. IL-4 has been shown to promote IgE production by B cells from atopic and non-at opic donors. In this study, the effects of natural exposure to pollens on IL-4-induced IgE synthesis by peripheral blood mononuclear cells o f atopic and non-atopic donors were examined. The results confirm prod uction of IgE in an IL-4 dose-dependent manner by PBMC cultures of the se two groups. When cultures were performed out of the pollen season, following stimulation by IL-4, no significant difference was observed between the levels of IgE produced by PBMC of atopic and non-atopic do nors. In contrast, upon natural exposure to pollens, significant highe r levels of IgE were measured in the atopic group than in the non-atop ic one. These results show that the pollen season influences the IL-4- induced IgE synthesis by PBMC of allergic patients and-are in keeping with seasonal rise of specific IgE antibodies.