Molecular Characterization of a Natural Latex Extract and Serological Diagnosis of Latex Allergy

Abstract

Latex is recognized as an allergen of increasing importance. It is essential to establish well characterized reference preparations in order to ensure the quality and consistency of subsequence extracts, but this is complicated by the lack of an international standard. In our investigations we have tested different latex raw materials. In highly sensitive patients skin tests with a latex extract can cause systemic reactions and therefore in vitro tests such as enzyme allergosorbent assay (EAST) or radioallergosorbent test (RAST) for the determination of latex specific IgE in patient sera may be an attractive option. However, the results will be influenced by the quality of the allergen disks used. In the absence of in vivo data, such as skin prick test results, it was only possible to compare the allergen disks produced with different latex allergic patients. Our investigations showed that a natural latex extract is the most suitable for the preparation of allergen disks as judged by the highest EAST classes. These extracts were characterized on a molecular basis by isoelectric focusing (IEF), sodium dodecyl sulfate Polyacrylamide gel electrophoresis (SDS-PAGE) and blotting techniques. The relative frequencies with which different allergens were recognized was deduced by constructing an allergogram which enabled us to identify two major, one intermediate and one minor allergen. With such characterized latex extract allergen disks can be prepared of a high quality and precise specific IgE measurements can be performed.