IgE binding capacity of synthetic and recombinant peptides of the major storage mite (Lepidoglyphus destructor) allergen, Lep d 2.
BACKGROUND
Lepidoglyphus destructor is an important non-pyroglyphid mite species in Europe and a dominant allergen in farming environments. The major allergen of L. destructor, Lep d 2, is a protein of 13.2 kD that is recognised by about 90% of sera RAST positive to this mite species.


METHODS
The cDNA of two isoallergens of the Lep d 2 has previously been sequenced and the protein expressed in different protein expression systems. In order to map the B-cell epitopes, the full length protein and the truncated forms of the protein have been expressed in Escherichia coli as glutathione-S-transferase (GST) fusion proteins. Recombinant Lep d 2 fragments and synthetic overlapping 15 mer peptides spanning Lep d 2 were probed with sera from patients allergic to storage mite.


RESULTS
The full-length (125 amino acids) GST fusion protein reacted strongly with patient IgE in Western blots and dot blots. Synthetic peptides failed to react with IgE antibodies from mite-allergic patients and the truncated fusion proteins displayed weak IgE-binding capacity.


CONCLUSIONS
We conclude that there are no dominant linear IgE-binding epitopes in Lep d 2. Recombinant or synthetic Lep d 2 fragments may, however, be further evaluated as hypoallergenic candidate molecules for specific immunotherapy.
Elfman
L H
LH
Department of Laboratory Medicine, Division of Clinical Immunology, Karolinska Hospital and Institute, Stockholm, Sweden.
Whitley
P
P
Schmidt
M
M
van Hage-Hamsten
M
M
D000485:Allergens / Q000737:chemistry*; D000595:Amino Acid Sequence; D000818:Animals; D000906:Antibodies / Q000276:immunology; D000939:Epitopes / Q000276:immunology; D006801:Humans; D015151:Immunoblotting; D007073:Immunoglobulin E / Q000276:immunology* / Q000378:metabolism*; D008925:Mites / Q000737:chemistry / Q000276:immunology; D008969:Molecular Sequence Data; D010455:Peptides / Q000276:immunology / Q000378:metabolism; D011506:Proteins / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000276:immunology; D011994:Recombinant Proteins / Q000276:immunology / Q000378:metabolism
D000485:Allergens; D000906:Antibodies; D000939:Epitopes; C090039:Lep d I allergen; D010455:Peptides; D011506:Proteins; D011993:Recombinant Fusion Proteins; D011994:Recombinant Proteins; D007073:Immunoglobulin E