Evolution in the understanding of cross-reactivities of respiratory allergens: the role of recombinant allergens.
The aim of this review is to show the impact of the use of purified and recombinant allergens to discriminate between co- and cross-sensitization to respiratory allergens. The author describes the evolution of diagnostic tests over the last decades; the tests initially allowed the detection of simultaneously positive cutaneous tests and/or simultaneous positivity of specific IgE to different allergen extracts, but they did not differentiate cross-sensitization from co-sensitization. RAST inhibition studies with crude extracts then established cross-reactivity, but did not identify the cross-reactive allergens involved. Later, immunoblot and CRIE inhibition were able to detect multiple cross-reactive allergens and to assess their physicochemical properties. But it is only since purified and recombinant allergens have been used in the different investigations that identification of cross-reactive allergens has been made possible at a molecular level. This historical approach is illustrated by examples selected from some of the main respiratory allergen sources: tree pollen, grass pollen, weed pollen, acarids, cockroaches and mammalians. For each of these allergen sources, the author gives an updated presentation of major and minor cross-reactive allergen molecules and refers to the last decade's major publications concerning immunochemical investigations carried out in the field of cross-reactive respiratory allergens. Emphasis is placed on the clinical applications for allergic patients: improvement in the accuracy of the diagnosis of sensitization, new concepts of immunotherapy based on genetically engineered hypoallergenic variants of cross-reactive allergens used alone or in combination, evaluation of allergen load with environmental tests using monoclonal antibodies against cross-reactive allergens.
Pauli
G
G
Service de Pneumologie, INSERM U425, Hôpital Lyautey, Hôpitaux Universitaires de Strasbourg, Strasbourg, France.
D000053:Acari; D000485:Allergens / Q000276:immunology*; D000818:Animals; D003058:Cockroaches; D003429:Cross Reactions / Q000276:immunology*; D006801:Humans; D008322:Mammals; D010944:Plants; D011058:Pollen / Q000276:immunology; D011994:Recombinant Proteins / Q000276:immunology; D012130:Respiratory Hypersensitivity / Q000175:diagnosis / Q000276:immunology*
D000485:Allergens; D011994:Recombinant Proteins