An in vitro cell based model for assessing the potential of allergens to release mediators through the cross-linking of IgE

The aim of this study was to examine the capacity of an in vitro model to test the potential of an allergen to cause cross-linking of IgE bound to the surface of mast cells. The model involved the passive sensitization of murine mast cells, with zearalenone IgE and subsequent exposure to anti IgE, zearalenone, zearalenone BSA (with up to nine bound zearalenone molecules) or peanut lectin. The extent of cross-linking was determined by measuring the release of IgE mediators TNF alpha and histamine. Release of TNF alpha from IgE sensitized cells increased following exposure to zearalenone-BSA, but not following exposure to zearalenone alone or to peanut lectin. Histamine release could not be quantified against background. The results suggested that the model could be used to test allergenic potential through the availability of epitopes to bind and cross-link IgE on the surface of mast cells. As IgE is species specific, the model was adapted fur use with a human cell system employing mast cells in lung fragments. TNF alpha release was measured, and the system was calibrated with the inhalant allergen from Timothy Grass and Timothy Grass specific IgE. (C) 1999 Published by Elsevier Science Ltd. All rights reserved.