Seasonal variation of IgE synthesis in vitro by human peripheral blood mononuclear cells

Seasonal variations in IgE antibody synthesis in vitro were studied in cultures of blood mononuclear cells (MNC) from 11 pollen allergic individuals. The IgE levels were significantly higher in two summer seasons than in the winter and spring between them. Net synthesis was confined to the summer in all but one of the patients. All the IgE in the cultures outside the pollen season represented preformed IgE which was present mainly (59%) in the monocyte fraction. Thus, preformed IgE seems to persist in monocytes at times when there is little de novo synthesis of IgE.