Effect of benzo (α) pyrene on the pollen allergenicity of Helianthus annuus L.

Benzo (a) pyrene (BaP) is an important part of diesel exhaust particles. Diesel exhaust particles have been shown to express adjuvant activity for sensitization against common allergens. The aim of this research is to elucidate the effects of BaP, as a major part of DEP, on the pollen allergenicity. Sunflower plants were treated with different concentrations of Benzo (α) pyrene (BaP) and allergenicity of the pollen extracts were compared by means of skin test, as well as analysis of blood eosinophil count and total IgE level in the guinea pigs. Non-treated and BaP-treated pollen were studied by SDS-PAGE for BaP-induced changes in protein banding profiles and also allergen band(s) were detected by immunoblotting method. Results showed that although non-treated pollen are effective in inducing allergic symptoms but allergenicity of BaP-treated pollen was increased considerably. SDS-PAGE showed protein banding profiles of pollen were changed and two new bands with molecular weight of 19 and 22 kDa appeared in BaP-treated pollen. Immunoblotting studies showed a band with molecular weight of 22 kDa in BaP-treated pollen that react strongly with anti-IgE, but there is not any similar band in non-treated pollen.