Effect of O3 and NO2 atmospheric pollutants on Platanus x acerifolia pollen: Immunochemical and spectroscopic analysis

Abstract

In the present study, the effects of two important oxidizing atmospheric pollutants (O3 and NO2) on the allergenic properties and chemical composition of Platanus x acerifolia pollen were studied. Pollen samples were subjected to O3 and/or NO2 under in vitro conditions for 6h at atmospheric concentration levels (O3: 0.061ppm; NO2: 0.025ppm and the mixture of O3 and NO2: 0.060 and 0.031ppm respectively). Immunoblotting (using Pla a 1 and Pla a 2 antibodies), infrared and X-ray photoelectron spectroscopy techniques were used. Immunochemical analysis showed that pollen allergenicity changes were different according to the pollutant tested (gas or mixture of gasses) and that the same pollutant gas may interact in a different manner with each specific allergen. The spectroscopy results showed modifications in the FTIR spectral features of bands assigned to proteins, lipids, and polysaccharides of the pollen exposed to the pollutants, as well as in the XPS spectra high-resolution components C 1s, N 1s, and O 1s. This indicates that while airborne, the pollen wall suffers further modifications of its components induced by air pollution, which can compromise the pollen function.