Molecular mimicry of the unidentified antigen of myeloma antibody IgE-ND.
Antigen-specific human IgE is in short supply. Thus, we sought to determine the yet unknown specificity of a widely available human IgE, namely the myeloma cell line U266-derived IgE-ND. For this purpose highly specific peptides able to mimic the putative antigen recognized by IgE-ND were isolated from phage-display random peptide libraries. Interestingly, we found linear sequence homologies of the IgE-ND-binding peptides with self antigens and a xenoantigen from Thiobacillus ferrooxidans. However, none of these antigens was recognized by IgE-ND. Nevertheless, our approach may be applied to identify antigen specificities of myeloma antibodies. Importantly, the mimotopes were anaphylactogenic in a histamine release assay using human basophils sensitized with IgE-ND. Thus, our mimotopes represent functional albeit synthetic antigens and may be used to study human antigen-specific IgE responses.
Thurnheer
M C
MC
Institute of Immunology and Allergology, University of Bern, Inselspital, Bern, Switzerland.
Zuercher
A W
AW
Miescher
S M
SM
Rudolf
M P
MP
Vogel
M
M
Stadler
B M
BM
D000595:Amino Acid Sequence; D000818:Animals; D000912:Antibodies, Neoplasm / Q000737:chemistry; D000918:Antibody Specificity; D000951:Antigens, Neoplasm / Q000276:immunology*; D001435:Bacteriophages / Q000276:immunology; D001667:Binding, Competitive; D016466:CHO Cells; D002478:Cells, Cultured; D006224:Cricetinae; D000939:Epitopes / Q000302:isolation & purification; D006801:Humans; D007073:Immunoglobulin E / Q000737:chemistry* / Q000378:metabolism; D018716:Molecular Mimicry / Q000276:immunology*; D008969:Molecular Sequence Data; D009101:Multiple Myeloma / Q000276:immunology*; D019151:Peptide Library; D017455:Receptors, IgE / Q000378:metabolism
D000912:Antibodies, Neoplasm; D000951:Antigens, Neoplasm; D000939:Epitopes; D019151:Peptide Library; D017455:Receptors, IgE; D007073:Immunoglobulin E