Allergy to natural rubber latex is a growing medical problem with life-threatening aspects. The aim of this study was to learn if guinea pigs could serve as a suitable model for immediate-type hypersensitivity to latex. Guinea pigs were immunized either with whole non-ammoniated latex extract, or with one of nine SDS-PAGE-separated components. Other animals were injected with electroeluted latex components localized on gel at 14, 24 and a cluster around 45 kD. Before and after immunization, sera from the animals were examined by ELISA, immunoblots, passive cutaneous anaphylaxis (PCA) and passive systemic anaphylaxis. Latex-specific antibodies were detected by ELISA and immunoblots in sera from all immunized animals. PCA assays showed that the guinea pigs had homocytotropic antibodies dilutible to 1:250. PCA was abolished when sera from animals immunized with allergens in alum were heated at 56°C for 30 min indicating the antibodies were of the E isotype. Passive systemic anaphylaxis was induced in 4 of 10 guinea pigs. The results show that guinea pigs are capable of making antibodies to latex protein components that mediate dermal and systemic anaphylaxis, paralleling the spectrum of clinical and laboratory findings of humans with immediate-type clinical latex hypersensitivity.

Background: IgE-mediated allergy to proteins present in natural rubber latex is a well-recognized problem. Latex contains a complex mixture of proteins ranging in molecular weight from 6 to > 200 kD. Objective: The aim of this study was to determine whether shared allergenic sites exist on separate latex components. Methods: Following electrophoresis, latex components at 14, 24, and 46 kD were electroeluted from SDS-polyacrylamide gels and used in ELISA inhibition and immunoblot inhibition studies of human latex-specific IgE antibodies. Results: A minimum of 4 major allergenic sites (for convenience labeled A through D) were found to exist in 3 components of nonammoniated latex. Minimally, 2 are present in the 14-kD component (A, B) and 3 in the 24-kD component (A-C). The 46-kD fraction has 3 or more antigenic sites (A, C, D) but lacks one (B) that is present in both the 14- and 24-kD components. Conclusions: Four different IgE-binding moieties were detected among three latex protein components (14, 24 and 46 kD). Some of these allergenic sites were shared by two or more components. Recovery of these and others from fragmented latex components will allow identification of their amino acid composition and their availability will ultimately lead to better diagnostic and therapeutic options for patients with latex allergy.