Identifying the allergenicity of maize pollen in Iran.

Background: Maize is a member of the Poaceae family, capable of producing large amounts of pollen grains which may constitute important allergens in spring and summer. The aim of this study was to determine the protein content of maize pollen and its allergenicity in guinea pigs.

Methods: The morphology of maize pollens was determined using light microscopy and scanning electron microscopy. The size of separated proteins was obtained by SDS-PAGE. A group of animals were immunized with maize pollen extract and the others were kept as control. After 40 days, the skin prick test was done in animals after blood sampling for counting the eosinophils. The allergenisity of proteins was identified by immunoblotting of transferred bonds using sera from sensitized guinea pigs.

Results: Pollen grains showed a spherical, monoporate structure with the scabrate exine surface. The SDS-PAGE indicated a major band of about 50 kD.We also showed increase in flare and wheal diameter following skin prick test in sensitized guinea pigs along with an elevated number of eosinophils. The presence of group 13 allergen (Zea m13) with molecular weight of ~ 50 kD was found in immunoblotting results.

Conclusion: This study showed one protein in maize pollen extract that could be considered as an allergen belonging to group 13 of allergen categories. However, further investigations should be scheduled for precise analysis of the proteins. This allergen can be used for diagnostic or therapeutic purposes (vaccination approaches) in allergic asthma patients.