Structural aspects of cross‐reactivity and its relation to
antibody affinity

• Published in: Allergy (Copenhagen) 2001-04, Vol.56 (s67), p.27-29
• Main Authors: Aalberse, Rob C., Kleine Budde, Ilona, Stapel, Steven O., Van Ree, Ronald
• Format: Article
• Language: English
• Subjects: allergen structure; cross‐reactivity; avidity; unstirred layer; mast cell triggering; Allergens - chemistry; Allergens - immunology; Allergens - metabolism; Animals; Antibody Affinity - immunology; Cross Reactions - immunology; Humans
• ISSN: 0105-4538; 1398-9995
• DOI: 10.1034/j.1398-9995.2001.00909.x

In the context of IgE/allergen interactions, affinity is largely determined by the stability of the allergen‐IgE complex: a low affinity is usually equated with a rapid dissociation of the complex. Regular solid‐phase assays are not well suited for affinity estimates because of multivalency effects, “unstirred layer” effects and “invisible” antibodies. Elution of IgE bound to solid‐phase coupled allergen might be a good measure of intrinsic affinity, provided that reassociation of antibodies is prevented by a high concentration of soluble allergen. Allergen‐mediated IgE‐dependent triggering of a mast cell is presumably a two‐step process. During the first step, the allergen is bound to a cell‐bound IgE antibody and dragged over the cell surface. The second step is the interaction between this cell‐bound allergen and another IgE antibody. The hypothesis is that the affinity requirements for the first step are higher than for the second. The implication is that a mast cell can be triggered by a single high‐affinity antibody in combination with one or more low‐affinity antibodies.