Recombinant allergens in specific immunotherapy: Current concepts and developments

Allergens produced by recombinant DNA technology have the ability to improve allergy diagnosis and are used as reference standards for analytical methods. In addition, the use of recombinant allergens in specific immunotherapy has long been considered potentially superior compared with the use of conventional extracts. The advantages are clear: a complex natural substance that is difficult to characterize is replaced by only those components relevant for treatment, which furthermore can be reproduced in pharmaceutical quality. The challenges faced here include selecting the relevant allergen molecules and establishing a manufacturing that meets all the regulatory requirements for marketing authorization. In addition to unmodified recombinant allergens, hypoallergenic variants with lower IgE reactivity can also be made by genetic engineering. Proof of concept has been demonstrated for both these approaches in clinical trials.