Ebner C, Szépfalusi Z, Ferreira F, Jilek A, Valenta R, Parronchi P, Maggi E, Romagnani S, Scheiner O, Kraft D
Institute of General and Experimental Pathology, University of Vienna, Austria.
J Immunol. 1993 Feb 1;150(3):1047-54.
Eleven T cell clones (TCC) with specificity for Bet v I were established from the peripheral blood of six birch pollen allergic donors. Bet v I is the major allergen of birch (Betula verrucosa) pollen and shows high homology to the major allergens of pollens of other trees within the order fagales (hazel, alder, hornbeam, oak, etc.), which represent important inhalant allergens in the northern hemisphere. The TCC were shown to react with purified natural, as well as with purified recombinant Bet v I. All clones showed the helper cell phenotype (CD3+CD4+) and expressed the TCR-alpha/beta. The cytokine production pattern in response to stimulation with allergen resulted in enhanced production of IL-4 in 9 of 11 clones. The clones were used for T cell epitope mapping on the Bet v I molecule. For this purpose, peptides with a length of 12 amino acids each and overlapping for 10 residues were synthesized following the amino acid sequence of Bet v I. These 75 peptides were used to stimulate Bet v I-specific T cell clones. Our experiments revealed 7 distinct T cell epitopes on the Bet v I molecule. The epitopes were scattered over the whole molecule, 2 sequences were in agreement with an algorithm previously described for the prediction of T cell epitopes. In 3 cases, we could identify distinct TCC specificities within single individuals. Furthermore, for each donor, none of the peptides representing epitopes for TCC inhibited the binding of IgE antibodies to Bet v I. These results suggest that T cells and IgE antibodies from the same individual recognize different structures on the Bet v I allergen.
从6名桦树花粉过敏供体的外周血中建立了11个对Bet v I具有特异性的T细胞克隆（TCC）。Bet v I是桦树（疣桦）花粉的主要过敏原，与壳斗目其他树木（榛树、桤木、鹅耳枥、橡树等）花粉的主要过敏原具有高度同源性，这些过敏原是北半球重要的吸入性过敏原。已证明TCC可与纯化的天然Bet v I以及纯化的重组Bet v I发生反应。所有克隆均表现出辅助性细胞表型（CD3 + CD4 +）并表达TCR-α/β。对过敏原刺激的细胞因子产生模式导致11个克隆中的9个克隆中IL-4的产生增加。这些克隆用于Bet v I分子上的T细胞表位定位。为此，按照Bet v I的氨基酸序列合成了长度为12个氨基酸且重叠10个残基的肽段。这75个肽段用于刺激Bet v I特异性T细胞克隆。我们的实验在Bet v I分子上揭示了7个不同的T细胞表位。这些表位分散在整个分子上，2个序列与先前描述的用于预测T细胞表位的算法一致。在3个案例中，我们可以在单个个体中鉴定出不同的TCC特异性。此外，对于每个供体，代表TCC表位的肽段均未抑制IgE抗体与Bet v I的结合。这些结果表明，来自同一个体的T细胞和IgE抗体识别Bet v I过敏原上的不同结构。
