Purification and IgE binding capacity of Der s 3, a major allergen from Dermatophagoides siboney.
BACKGROUND
Sensitization to the house dust mite Dermatophagoides siboney has been demonstrated in asthmatic patients. Previously, Dermatophagoides siboney group 1 and group 2 allergens, named Der s 1 and Der s 2, respectively, have been purified.


OBJECTIVE
The aim of this study was to purify and to study the IgE reactivity of 30 kDa component, suspected to correspond to group 3 allergens.


METHODS
The protein was purified by affinity chromatography using anti-Der f 3 monoclonal antibodies and semi-preparative SDS-PAGE. The IgE binding capacity of the purified fractions was tested with sera from 106 mite-sensitive asthmatic patients using a modified chemiluminiscent method.


RESULTS
Affinity chromatography resulted in fractions containing the 30 kDa component which was further purified to homogeneity by SDS-PAGE. Seventy-three per cent of the sera showed IgE reactivity to this protein, indicating that it is a major allergen. The protein also reacted with anti Der f 3 polyclonal antibodies and had tryptic activity. There were differences in the reactivity to Der s 3 according to the age of the patients.


CONCLUSIONS
Based on the frequency of IgE reactions and the reactivity with antibodies directed to Der f 3, it is proposed to name this 30 kDa allergen from D. siboney, Der s 3.
Ferrándiz
R
R
Department of Paediatrics, Linköping University Hospital, Sweden.
Casas
R
R
Dreborg
S
S
D000293:Adolescent; D000328:Adult; D000375:Aging / Q000276:immunology; D000485:Allergens / Q000276:immunology*; D000818:Animals; D039741:Antigens, Dermatophagoides; D002648:Child; D002675:Child, Preschool; D002846:Chromatography, Affinity; D004591:Electrophoresis, Polyacrylamide Gel; D006023:Glycoproteins / Q000276:immunology / Q000302:isolation & purification*; D006801:Humans; D007073:Immunoglobulin E / Q000276:immunology*; D007223:Infant; D008163:Luminescent Measurements; D008925:Mites / Q000276:immunology*; D008970:Molecular Weight
D000485:Allergens; D039741:Antigens, Dermatophagoides; D006023:Glycoproteins; D007073:Immunoglobulin E