Associations of allergenic soybean proteins with piglet skin allergic reaction and application of polyclonal antibodies

Abstract

A skin prick test was conducted to evaluate the skin allergic reaction of piglets caused by allergenic proteins contained in soybean meal. The data accumulated from subcutaneous piglet skin tissue indicated that allergenic proteins contained in soybean meal crude extracts, even in low dosage levels (7 μg), caused immunological redness and inflammation within 5 min. The dosages above 200 μg of β-conglycinin caused inflammation covering a larger area. The glycinin had less of an influence on skin allergenic reaction dosages than β-conglycinin did. The antibodies used for β-conglycinin and glycinin subunits did not exhibit cross-recognition to other subunits or Leguminosae members, such as green beans, lupins and red beans. The polyclonal antibodies further indicated that some allergenic proteins were present after examining soybean meal fermented products individually by Aspergillus or Lactobacillus. None of the allergenic proteins were detected in soybean meal underwent two-stage fermentation. The skin prick test was found to be a convenient method for evaluating the skin allergic reaction of soy allergenic proteins in piglets. The produced polyclonal antibodies are based on subunits of allergenic proteins and can be used to detect the allergenic proteins present in soya products and soybean meal fermented products.