Structural analysis of human IgE monoclonal antibody epitopes on dust mite allergen Der p 2.
J Allergy Clin Immunol
; 154(2): 447-457, 2024 Aug.
Article
in En
| MEDLINE
| ID: mdl-38697404
ABSTRACT
BACKGROUND:
Human IgE (hIgE) mAbs against major mite allergen Der p 2 developed using human hybridoma technology were used for IgE epitope mapping and analysis of epitopes associated with the hIgE repertoire.OBJECTIVE:
We sought to elucidate the new hIgE mAb 4C8 epitope on Der p 2 and compare it to the hIgE mAb 2F10 epitope in the context of the allergenic structure of Der p 2.METHODS:
X-ray crystallography was used to determine the epitope of anti-Der p 2 hIgE mAb 4C8. Epitope mutants created by targeted mutagenesis were analyzed by immunoassays and in vivo using a human high-affinity IgE receptor (FcεRIα)-transgenic mouse model of passive systemic anaphylaxis.RESULTS:
The structure of recombinant Der p 2 with hIgE mAb 4C8 Fab was determined at 3.05 Å. The newly identified epitope region does not overlap with the hIgE mAb 2F10 epitope or the region recognized by 3 overlapping hIgE mAbs (1B8, 5D10, and 2G1). Compared with wild-type Der p 2, single or double 4C8 and 2F10 epitope mutants bound less IgE antibodies from allergic patients by as much as 93%. Human FcεRIα-transgenic mice sensitized by hIgE mAbs, which were susceptible to anaphylaxis when challenged with wild-type Der p 2, could no longer cross-link FcεRI to induce anaphylaxis when challenged with the epitope mutants.CONCLUSIONS:
These data establish the structural basis of allergenicity of 2 hIgE mAb nonoverlapping epitopes on Der p 2, which appear to make important contributions to the hIgE repertoire against Der p 2 and provide molecular targets for future design of allergy therapeutics.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Immunoglobulin E
/
Mice, Transgenic
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Antigens, Dermatophagoides
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Arthropod Proteins
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Antibodies, Monoclonal
/
Epitopes
Limits:
Animals
/
Humans
Language:
En
Journal:
J Allergy Clin Immunol
/
J. allergy clin. immunol
/
Journal of allergy and clinical immunology
Year:
2024
Type:
Article