Immunoblot analysis of IgE-binding antigens in paprika and tomato pollen

Background: The high incidence of occupational allergy in horticulture has only recently been recognized. We determined IgE against pollen and fruit f rom paprika and tomato plants in sera from 3 greenhouse workers and in 3 se ra from food-allergic patients. Methods: Proteins in extracts of paprika an d tomato pollen were incubated with patients' sera after covalent coupling of these proteins to agarose beads, or in immunoblots. Results: IgE against paprika pollen, but no IgE against tomato pollen, was found in serum from 2 greenhouse workers who worked with paprika plants only. IgE binding of th ese 2 sera to agarose-bound paprika pollen extract could be inhibited by pa prika pollen but not by tomato pollen extract. A greenhouse worker, who cul tivated tomato plants, had IgE against both tomato and paprika pollen, IgE binding of this serum to agarose-bound paprika pollen extract could be inhi bited by both paprika pollen and tomato pollen extract. Three food-allergic patients also had FIE against tomato and paprika pollen. IgE from 2 food-a llergic patients recognized IgE-binding structures in paprika or tomato pol len that were also present in fruit from the corresponding plant, In contra st, no substantial cross-reactivity was observed between paprika pollen and fruit towards IgE from 3 greenhouse workers, In 4 of 5 sera that were posi tive in the paprika pollen immunoblot major IgE binding to allergens of abo ut 30 and 64 kD occurred, Conclusion:The presence of IgE against paprika or tomato pollen is not restricted to workers in horticulture; IgE against th ese pollen can also be present in food-allergic patients who have serum IgE against paprika and/or tomato fruit. Copyright (C) 2000 S. Karger AG. Base l.