Interest of Two-Dimensional Electrophoretic Analysis for the Characterization of the Individual Sensitization to Latex Allergens

BACKGROUND/OBJECTIVE: Latex allergy is a type 1 hypersensitivity reaction that mainly affects high-risk populations such as health care workers, spina bifida-affected or multiply-operated children. Ten molecules have so far been identified and registered as latex allergens (Hev b 1 to Hev b 10). The aim of the present investigation was to identify the major latex allergens by an individual analysis of the IgE response of latex-allergic patients to latex proteins separated by two-dimensional (2-D) gel electrophoresis. MATERIALS AND METHODS: Latex proteins from a sap or a glove extract were separated by 2-D electrophoresis and transferred to a nitrocellulose membrane. Each membrane was incubated with the serum of one latex-allergic patient. The most frequently recognized latex allergens were characterized in sap and glove extracts using monoclonal antibodies or amino acid microsequencing. RESULTS: The one-dimensional screening of 54 patient sera revealed 4 major bands recognized by IgE. The 2-D analysis of the sensitization to latex allergens allows the identification of allergen isoforms and the characterization of an individual response diversity. Hev b 6.01 was recognized by 88.9% of the patients. Protein spots around 14 kD were recognized by 48.1% of the patients and corresponded to Hev b 6.03 as well as other proteins. A not yet characterized doublet of acidic proteins with molecular masses of 43 and 94 kD was recognized by 20.4% of the sera. Only 5.5% of the sera did not recognize any of these 4 major allergens. Hev b 1 is the main protein from the glove extract but was not constantly found in sap extracts. CONCLUSIONS: One-dimensional electrophoretic analysis of the allergen is usually not sufficient to characterize the individual specificity of the IgE response to latex allergens. Latex-glove proteins which are allergens can be absent from the sap extracts and the sensitization to these allergens could be underestimated. Individual 2-D analysis of the sensitization to latex allergens is useful to define the best allergen mixture required for diagnosis and needed for individual therapy monitoring.