Multiple T cell specificities for Bet v I, the major birch pollen allergen, within single individuals. Studies using specific T cell clones and overlapping peptides.
Twenty-five T cell clones specific for Bet v I were established from the peripheral blood of two birch pollen-allergic patients. The T cell epitopes of these clones were mapped using dodecapeptides overlapping for 2 amino acids (neighbors share 10 residues) spanning the whole amino acid sequence of the protein (159 amino acids). In total, 7 epitopes could be detected. One donor displayed 6 distinct T cell specificities for the Bet v I molecule in 14 T cell clones; for the other donor, 4 stimulating peptides for 11 clones could be identified. Two T cell epitopes were recognized by both subjects. One of these might represent an immunodominant epitope located at amino acid position 77-92 of the Bet v I molecule, as in 13/25 T cell clones activation could be induced by this amino acid sequence. One T cell clone reacted with purified pollen-derived Bet v I, but neither with any peptide synthesized according to a Bet v I-encoding cDNA nor with the respective recombinant protein. Upon stimulation with allergen, the majority of the clones (21/24) revealed the TH0 or TH2 type of cytokine production (interleukin-4 production), indicating their importance in the pathogenesis of the allergic disease.
Ebner
C
C
Institute of General and Experimental Pathology, University of Vienna, Austria.
Schenk
S
S
Szépfalusi
Z
Z
Hoffmann
K
K
Ferreira
F
F
Willheim
M
M
Scheiner
O
O
Kraft
D
D
D000485:Allergens / Q000737:chemistry / Q000276:immunology*; D000595:Amino Acid Sequence; D002478:Cells, Cultured; D002999:Clone Cells; D000939:Epitopes; D006801:Humans; D066298:In Vitro Techniques; D007371:Interferon-gamma / Q000096:biosynthesis; D015847:Interleukin-4 / Q000096:biosynthesis; D008213:Lymphocyte Activation; D008969:Molecular Sequence Data; D010455:Peptides / Q000276:immunology; D011058:Pollen / Q000737:chemistry / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*; D014197:Trees
D000485:Allergens; D000939:Epitopes; D010455:Peptides; D015847:Interleukin-4; D007371:Interferon-gamma