Identification of allergenic potency of Latex-chemicals in the auricular lymph node assay in the mouse
Identificatie van de allergene potentie van Latex chemicalien met behulp van de auriculaire lymfklier assay in de muis
de Jong WH, Tentij M, Legtenberg RJ, van de Vliet H, Vandebriel RJ, van Loveren H
RIVM Report 640010001
In recent years the occurence of latex allergy has been increased due to the preventive use of latex gloves. The use was studied of the ALNA as a detector of allergenic properties of chemicals in latex gloves. In this so called auricular lymph node assay (ALNA) a test compound is administered epicutaneously at the dorsum of the ears for three consecutive days. Several days after administration, the draining (auricular) lymph node was removed and weight, cell number and lymphocyte proliferation were determined as parameters for activation. An increased value of these parameters indicates interaction with the immune system and hence immunogenic cq. allergenic potential. Generally an increase in activity as compared to vehicle treated control lymph nodes, expressed as stimulation index, with a factor of 3 or more is considered a positive reaction. Several chemicals used in the latex production process and known to induce Type IV allergy were tested, including tetramethylthiuramdisulfide (TMTD) , zincdimethyldithiocarbamate (ZDMC), 2-mercapto-benzothiazole (MBT) and diethylamine (DEA). For the evaluation of the ALNA, dinitrochlorobenzene (DNCB) and trimellitic anhydride (TMA) were used as model compounds. Latex allergy is not only caused by chemicals but also by proteins. In pilot experiments with ovalbumin as a model protein, it was investigated whether the ALNA assay can be used for the detection of allergenic properties of proteins. The results show that, using the ALNA, sensitizing activity of TMA and DNCB and also of the rubber additives TMTD, ZDMC, MBT and DEA can be identified. Preliminary data indicate that it might be possible to use the ALNA to identify sensitizing activity of proteins and glove extracts. However, these results need further confirmation.