Human auto-anti-idiotypic antibodies to mite-specific IgE can degranulate human basophils in vitro.
BACKGROUND
Anti-idiotypic antibodies (anti-Ids) to specific IgE antibodies are formed spontaneously during an anti-allergen immune response and can be induced by immunotherapy. Although anti-Ids can down-regulate the production of IgE antibodies, at least in experimental models, their possible role in the modulation of target cell reactivity remains ill-defined.


OBJECTIVE
The capacity of human anti-Ids to modulate the release of histamine was examined in an in vitro system of human basophil degranulation. Anti-Ids were prepared from the serum of six Dermatophagoides pteronyssinus (Dp)-hypersensitive patients suffering from atopic dermatitis and who had never been desensitized. Basophils were obtained from the blood of atopic donors. The extent of histamine release was determined using a fluorometric assay.


RESULTS
We show that: anti-Ids trigger the release of histamine in an allergen-specific, dose- and IgE-dependent manner; the release is not due to the presence of allergen and/or anti-IgE antibodies; and that the degranulating activity can be removed by absorption with affinity-purified anti-Dp antibodies of the corresponding patient.


CONCLUSIONS
These results indicate that spontaneously produced human anti-Ids can modulate the reactivity of human basophils.
Weyer
A
A
Service d'Allergologie, Institut Pasteur, Paris, France.
Le Mao
J
J
Etievant
M
M
David
B
B
Guinnepain
M T
MT
Saint-Remy
J M
JM
D000485:Allergens / Q000276:immunology; D000818:Animals; D000888:Antibodies, Anti-Idiotypic / Q000494:pharmacology*; D000918:Antibody Specificity; D039741:Antigens, Dermatophagoides; D001323:Autoantibodies / Q000494:pharmacology*; D001491:Basophils / Q000187:drug effects*; D006023:Glycoproteins / Q000276:immunology*; D006636:Histamine Release / Q000187:drug effects*; D006801:Humans; D007073:Immunoglobulin E / Q000276:immunology*; D008925:Mites / Q000276:immunology*
D000485:Allergens; D000888:Antibodies, Anti-Idiotypic; D039741:Antigens, Dermatophagoides; D001323:Autoantibodies; D006023:Glycoproteins; C026408:anti-IgE antibodies; D007073:Immunoglobulin E