Occupational sensitization to ribosome-inactivating proteins in researchers

• Published in: Clinical and experimental allergy 2005-10, Vol.35 (10), p.1354-1360
• Main Authors: Szalai, K., Schöll, I., Förster-Waldl, E., Polito, L., Bolognesi, A., Untersmayr, E., Riemer, A. B., Boltz-Nitulescu, G., Stirpe, F., Jensen-Jarolim, E.
• Format: Article
• Language: English
• Subjects: Adult; Aged; Allergic diseases; Biological and medical sciences; Biomedical Research; Cross Reactions; cross-reactivity; Drug Hypersensitivity - etiology; Drug Hypersensitivity - immunology; Electrophoresis, Polyacrylamide Gel - methods; Enzyme-Linked Immunosorbent Assay - methods; Female; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Humans; IgE; Immunoglobulin E - metabolism; Immunopathology; Male; Medical sciences; Middle Aged; occupational; Occupational Diseases - chemically induced; Occupational Diseases - immunology; Occupational Exposure - adverse effects; Plant Extracts - adverse effects; Plant Extracts - immunology; Plant Proteins - adverse effects; Plant Proteins - immunology; Research Personnel; Ribosomes - drug effects; RIPs; type I allergy
• ISSN: 0954-7894; 1365-2222
• DOI: 10.1111/j.1365-2222.2005.02338.x

Summary Background Ribosome‐inactivating proteins (RIPs) are expressed in many plants. Because of their anti‐infectious and anti‐proliferative effects, intensive research is going on for applying these toxins in therapy against viral infections or malignancies. Recently, we demonstrated that type I allergy against RIPs from elderberry can occur. Objective Stimulated by our study, a group of RIP researchers reported that some of the employees had suspected allergy to RIPs. Methods and Results We tested their sera in ELISA on natural RIPs. Specific IgE in four subjects were found against dianthin30, gelonin, momordin, PAP‐S, saporin, ricin and volkensin. In contrast, asparin and lychnin did not show any IgE binding. When separating extracts of plants containing the toxins in SDS‐PAGE, RIPs appeared to be the predominant constituents. Interestingly, among the other plant proteins, they were exclusively recognized by IgE in immunoblot. RIPs derived from close botanical families share high sequence homologies. Nevertheless, in IgE inhibition experiments with human sera, cross‐reactivity between RIPs also derived from non‐related plants could be demonstrated. Conclusion We conclude that sensitization and IgE induction to RIPs may occur upon exposure. This has to be considered when applying them in therapy against malignancies or viral infections.