ABSTRACT
Allergy is an expanding problem in the industrialized countries. Allergenic proteins, the allergens, causing the allergic symptoms are ubiquitous materials in the environment, normally not harmful for individuals not sensitized to them. In contrast, sensitized individuals who have specific immunoglobulin E against the allergen as a result of activation of the immune system can develop immediate, even fatal allergic reactions. Sensitization to in door allergens, for example to those derived from pets, is often associated with more severe forms of allergic diseases, such as asthma. Recent years have shown that the major mammalian allergens causing respiratory sensitization belong to the lipocalin family o f proteins. Reasons for this remain to be fully elucidated but it appears that lipocalin allergens exhibit immuno logical features that may account for their allergenic capacity.
