Search

To date, the potency of allergen products in Europe is expressed in manufacturer-specific units relative to a product-specific in-house reference. Consequently, cross-product comparability of allergen products from different manufacturers with respect to strength and efficacy is impossible. The Biological Standardisation Programme (BSP) project BSP090 addresses this issue via the establishment of reference standards in conjunction with ELISA methods for the quantification of major allergens in allergen products. Since the initiation of BSP090, the recombinant major allergen Bet v 1 has been adopted by the European Pharmacopoeia Commission as a Chemical Reference Substance (CRS). In parallel, two sandwich ELISA systems for quantification of Bet v 1 were found suitable in preliminary phases of BSP090 to be validated in a large collaborative study. In this study, the candidate ELISA systems were compared with respect to accuracy, precision and variability. Thirteen participating laboratories tested model samples containing the CRS as well as spiked and unspiked birch pollen extracts. Both in pre-testing and in the collaborative study, the 2 candidate ELISA systems confirmed their suitability to quantify recombinant and native Bet v 1. As no clear-cut decision for one of the ELISA systems could be made based on the results of the collaborative study, a post-study testing was performed. Bet v 1 content of 30 birch pollen allergen products was determined in parallel in both ELISA systems. Consequently, 1 candidate ELISA system was selected to be proposed as the future European Pharmacopoeia standard method for Bet v 1 quantification.

Ricin can be detected in cosmetics at 0.005 microg/mL in the analytical sample using lateral flow devices (LFDs). Wheat germ, an ingredient used in skin care products is also a potential source of wheat lectin. False positives were observed when wheat lectin was added to LFDs from two manufacturers, irrespective of whether the LFD was specific for ricin, Staphylococcus enterotoxin B (SEB), or botulinum toxin. In contrast, pea and peanut lectins did not cause false positives. Substitution of the buffer supplied with the LFDs with a buffer containing 2.5% non-fat milk powder eliminated the occurrence of false positives. This substitution increased the LOD to 0.01 microg/mL ricin, which is an acceptable level for screening cosmetics for contamination by ricin.