Key pollen allergens in North America.
OBJECTIVE: To discuss major pollen aeroallergens in North America that are essential for effective immunotherapy and to propose a list of pollen aeroallergens that could be prioritized for allergen standardization. DATA SOURCES: PubMed was used to search the existing medical literature. No date restrictions were used. Keywords included allergy, aeroallergen, taxonomy, cross-reactivity, pollen, and specific genus and species names. RESULTS: Tree species possess relatively unique allergens, and representative members should be chosen at the genus or family level. In the Composite family, there is significant cross-reactivity between ragweed species within the Ambrosia genus. Selection of one species should be sufficient for skin testing and immunotherapy. Extensive allergenic cross-reactivity exists among grasses. Selection of timothy grass alone or in combination with a single northern grass species provides adequate coverage in the northeastern regions of North America. CONCLUSIONS: One of the goals within the field of allergy should be to identify high-priority targets for future development of standardized commercial extracts. The standardization of increasing numbers of allergen extracts potentially benefits the discipline of allergy by facilitating transfer of care among physician practices, improving uniformity of patient care, and providing a template on which geographically specific extract choices can be built.