Tk. Johnsen et al., FURTHER CHARACTERIZATION OF IGE-BINDING ANTIGENS IN HORSE DANDER, WITH PARTICULAR EMPHASIS ON GLYCOPROTEIN ALLERGENS, Allergy, 51(9), 1996, pp. 608-613
IgE-binding components in an extract of horse dander were analyzed, es
pecially with regard to the glycoprotein allergens. After SDS-PAGE und
er reducing conditions and blotting, several of the glycoprotein IgE-b
inding components, including two distinct bands of 27 and 31 kDa, were
detected. Together with several other bands, they were shown to bind
to the lectins Sambucus nigra agglutinin (SNA) and Datura stramonium a
gglutinin (DSA), indicating terminal sialic acid linked alpha 2-->6 to
galactose, and galactose linked beta 1-->4 to N-acetylglucosamine, re
spectively. Carbohydrate analysis after SDS-PAGE and blotting showed t
he presence of mannose, galactose, N-acetylglucosamine, and N-acetyl n
euraminic acid in the 27-kDa band. The 14.4-kDa glycoprotein component
lost its IgE-binding activity after periodate oxidation. Minor differ
ences in allergenic activity in the other glycoprotein allergenic comp
onents were also detected, indicating that the carbohydrate part of th
e molecule seems to play a role in the IgE-binding activity. Two-dimen
sional electrophoresis and subsequent immunoblotting were performed to
estimate the approximate number, molecular mass, and pi of IgE-bindin
g components. This resulted in a cluster of such components on the blo
t membrane.