Bruserud O, Elsayed S, Pawelec G
2nd Department of Internal Medicine, Medizinische Klinik, Tübingen, Germany.
Mol Immunol. 1992 Sep;29(9):1097-104. doi: 10.1016/0161-5890(92)90042-v.
The streptokinase molecule (415 AA) was cleaved at methionine 237, 347 and 370 yielding four polypeptide fragments. Human HLA-class II restricted streptokinase-specific T cell clones and cell lines (CD2+, CD3+, CD4+, CD8-, TCR alpha beta+, TCR gamma delta-) recognized antigenic epitopes on all four fragments AA 1-236, AA 238-346, AA 348-369 and AA 371-415. T cell clones recognizing fragment AA 1-236 were restricted by at least two different HLA-class II elements, this indicating that more than one antigenic epitope can be recognized on this fragment. In addition, two streptokinase-specific T cell clones recognized only the intact molecule and none of the molecular fragments. These two clones probably recognized an antigenic epitope including one of the methionine residues used for molecular cleavage. We conclude that T cell proliferative responses to streptokinase are determined by recognition of at least five different antigenic epitopes distributed along the entire streptokinase polypeptide chain.
链激酶分子（415个氨基酸）在甲硫氨酸237、347和370处被切割，产生四个多肽片段。人HLA - II类限制性链激酶特异性T细胞克隆和细胞系（CD2 +、CD3 +、CD4 +、CD8 -、TCRαβ +、TCRγδ -）识别所有四个片段（氨基酸1 - 236、氨基酸238 - 346、氨基酸348 - 369和氨基酸371 - 415）上的抗原表位。识别片段氨基酸1 - 236的T细胞克隆受至少两种不同的HLA - II类分子限制，这表明在该片段上可识别不止一个抗原表位。此外，两个链激酶特异性T细胞克隆仅识别完整分子，不识别任何分子片段。这两个克隆可能识别了一个包含用于分子切割的甲硫氨酸残基之一的抗原表位。我们得出结论，对链激酶的T细胞增殖反应是由识别沿整个链激酶多肽链分布的至少五种不同抗原表位所决定的。
