Identification of shared allergenic components from four common and dominant pollen taxa of Arecaceae

Abstract

The Arecaceae (palm) family is predominantly distributed in the tropics and subtropics. Areca catechu (betel nut), Borassus flabellifer (fan palm), Cocos nucifera (coconut) and Phoenix sylvestris (date sugar palm) are widely cultivated all over the Indian subcontinent. These members are anemophilous and release numerous pollen grains in air during pollination period. These grains are known to cause IgE-mediated human respiratory allergy. In this context, a study was conducted on 448 respiratory allergic subjects, sensitive to one/more of the relevant pollen types from Greater Kolkata and suburbs, by case study, skin reaction test, IgE-ELISA, immunoblot and immunoblot inhibition. 72 and 48 kDa components from Areca, 100 kDa component from Borassus, 16 kDa component from Cocos and 66 and 33 kDa components from Phoenix pollen were found to be inhibited by the other three respective pollen extracts. This may be due to the sequence and structural homology of the epitopes. Therapeutic and diagnostic use of these shared components carrying most of the IgE-epitopes could minimize the hazards of impurities and side effects in allergen-specific immunotherapy/hypo-sensitization of palm pollen susceptible allergic patients.