Increasing of allergy potency of pollen grains in helianthus annuus l. under benzo(á) pyrene (BAP) exposure

Background: Allergy prevalence was increased in recent years dramatically. The reason of this phenomenon was not clear but there is a scientific attention to air pollution. Diesel exhaust particles (DEP) are a major part of air pollutants that express both adjuvant activity for sensitization against common allergens and enhancing sensitized individuals. Benzo(α) Pyrene (BAP) is considered as the most important part of DEP. The aim of this research was study of the effect of BAP on allergenecity of pollen grains in Helianthus annuus L.

Method: In this research, H. annuus L. Var.  record plants were grown from seed in green house controlled condition and shoots treated by different concentration of BAP solutions in phosphate buffer saline (PBS) (0.002, 0.02, 0.04 g/l) daily. Controls were sprayed by PBS.  Pollen grains were collected and allergy potency of pollen grains was compared in different experimental groups and controls. Allergenecity of pollens was studied by means of skin prink test, determination of blood cells and evaluation of total IgE in  studied groups using sensitized guinea pigs as an experimental model. Pollen proteins were also studied by SDS-PAGE and Immuno-blotting method for BAP-induced changes in protein profile and detection of allergen bands.

Result: Comparing of allergy potency of different pollen extracts showed that allergic skin reactions in animals that treated by polluted pollen grains was 2-3 times more than the groups treated by normal pollen extract and 5-6 times more than BAP treated group. Eosinophil number and IgE level, as allergy indicators, were also increased considerably in the blood of the groups treated by BAP exposed pollen grains than control ones. Results of SDS-PAGE showed that there are two additional bands in the BAP treated pollen grains. Immuno-blotting study of pollen proteins showed that new bands act as allergens that are reacted with IgE strongly.

Conclusion: Results of this research work concluded that BAP could increase the allergy potency of H. annuus pollen grains and also cause to formation of new protein bands that act as new allergens.