Friedl-Hajek R, Breiteneder H, Bohle B, Fischer G, Ebner C, Scheiner O
Department of General and Experimental Pathology, University of Vienna, Australia.
Int Immunol. 1998 Nov;10(11):1725-32. doi: 10.1093/intimm/10.11.1725.
We analyzed the cDNA sequence data of complementarity determining regions (CDR3) of epitope mapped alphabeta TCR of T cell clones (TCC). The TCC were specific for the major timothy grass (Phleum pratense) pollen allergen Phl p 1 and were derived from the peripheral blood of seven unrelated grass pollen-allergic individuals. Each TCR recognized one of two immunodominant T cell epitopes, PP73 or PP103, of Phl p 1. Although a diversity of recombined V and J segments was observed, amino acid motifs as long as five residues were conserved among CDR3 loops of TCR from TCC of different atopic individuals specific for the same peptide. The conserved sequences could comprise as much as 60% of the CDR3. All amino acid residues of the motifs of the CDR3beta and most of the CDR3alpha of all TCR used in this study were encoded by randomly added nucleotides. This indicates that they were specifically selected for by the peptide bound to the MHC class II molecule. For one selected patient, a larger number of TCC, specific for PP103, was analyzed. The TCR repertoire was limited to three different TCR. The same MHC class II molecule, DRB1*1301, was identified to present PP103 to each of the three TCR.
我们分析了T细胞克隆（TCC）中抗原表位定位的αβTCR互补决定区（CDR3）的cDNA序列数据。这些TCC对主要的梯牧草（Phleum pratense）花粉过敏原Phl p 1具有特异性，且来源于7名无亲缘关系的草花粉过敏个体的外周血。每个TCR识别Phl p 1的两个免疫显性T细胞表位之一，即PP73或PP103。尽管观察到重组的V和J片段具有多样性，但对于同一肽具有特异性的不同特应性个体的TCC的CDR3环中，长达五个残基的氨基酸基序是保守的。保守序列在CDR3中所占比例可达60%。本研究中使用的所有TCR的CDR3β基序的所有氨基酸残基以及大多数CDR3α基序均由随机添加的核苷酸编码。这表明它们是由与II类MHC分子结合的肽特异性选择的。对于一名选定的患者，分析了大量对PP103具有特异性的TCC。TCR库限于三种不同的TCR。已确定相同的II类MHC分子DRB1*1301将PP103呈递给这三种TCR中的每一种。
