Airborne Poaceae pollen in Porto (Portugal) and allergenic profiles of several grass pollen types

This work aims to investigate the presence of airborne grass pollen and to identify antigenic and allergenic profiles from eight different grass species collected in the Porto region (Portugal). Poaceae airborne pollen, sampled using a Hirst-type volumetric trap during 2003-2007, was the second most abundant type, and high concentrations were found from April to August. Pollen proteins extracted from the eight grass species collected were separated by SDS-PAGE, being the allergenic profile investigated by immunoblotting using sera from atopic patients and maize profilin polyclonal antibody (ZmPRO3). Pollen extract profiles showed several bands ranging from 10 to 97 kDa. In immunoblotting studies, a low molecular weight protein (12-13 kDa) was recognized by profilin antibody. Also, in all pollen extracts except Zea mays, the IgE binding proteins of 12-13 kDa were detected in sera from the 25 patients with different sensitization profiles presenting high IgE values (> 80 kU/l). This protein can be considered as a potential causal agent of the allergic respiratory diseases.