LYMPHOCYTE-PROLIFERATION RESPONSE TO EXTRACTS FROM DIFFERENT LATEX MATERIALS AND TO THE PURIFIED LATEX ALLERGEN HEV-B-1 (RUBBER ELONGATION-FACTOR)

Background: Type I allergy to latex is a growing problem, especially a mong health care workers. A detailed study of the peripheral blood cel l responses to latex allergens has not been reported. Methods: Periphe ral blood mononuclear cells of patients and healthy subjects were isol ated and stimulated with protein extracts from latex sap and latex glo ves and the purified latex allergen Hev b 1 (rubber elongation factor) at different concentrations to determine the antigen-specific prolife ration response. The examined patients were sensitized to latex by occ upational exposure (n = 23) and had rhinitis, conjunctivitis, contact urticaria, and/or asthma. Two control groups of nonsensitized subjects were studied: one occupationally exposed to latex (n = 8), and the se cond, not exposed to latex (n = 8). Results: In general, only latex-ex posed subjects responded to the different latex antigen preparations. Lymphocyte proliferation responses to latex sap were found in 65% of l atex-sensitized subjects and in 37.5% of the latex-exposed healthy sub jects. Latex glove extract induced a significant proliferative respons e in 47.8% of latex-sensitized patients and in 25% of the latex-sensit ized individuals. Hev b 1 induced lymphocyte proliferation responses i n 52% of the latex-sensitized patients and in 25% of the latex-exposed subjects, indicating that Hev b 1 is relevant antigen in these latex- sensitized and latex-exposed groups. Peripheral blood mononuclear cell s of 39.1% of the latex-sensitized subjects responded to all three all ergen preparations (latex sap and latex glove extract, as well as Hev b 1). We could find no correlation between latex-specific IgE level an d latex-induced lymphocyte proliferation response. Conclusion: Our dat a indicate that the 14 kd protein Hev b 1 is a relevant allergen in he alth care workers. It can be detected by specific IgE antibodies to He v b 1, as well as in lymphocyte proliferation assay. In addition, our study suggests that antigen-specific proliferation response to latex i s associated with exposure to latex, but not with the level of specifi c latex IgE. This may be useful for the evaluation and prediction of l atex hypersensitivity development.