Idenification of tumor antigens in pancreatic cancer by proteomic analysis.

1.本项目的目的是通过蛋白质组学方法鉴定诱导胰腺癌患者体液反应的肿瘤特异性抗原。分别对5名胰腺癌患者和5名健康人的血清进行免疫印迹（Western blot）分析。仅在癌症患者中检测到的斑点通过质谱分析来鉴定肿瘤特异性自身抗体识别的抗原。不幸的是，虽然我尝试了几种实验条件，但我无法通过这种方法得到有效和可重复的结果。因此，我决定修改方法。简单地说，用从胰腺癌患者和健康受试者中纯化的自身抗体免疫沉淀来自癌细胞系的溶解蛋白等分，然后进行二维PAGE和质谱分析。目前正在进行的工作是鉴定可能有效的新型肿瘤抗原…更多针对胰腺癌患者的特异性免疫治疗候选者。以肽为基础的疫苗疗法，旨在引发t细胞免疫肿瘤，是治疗癌症患者的一种有吸引力的方法。我们试图鉴定用于抗原特异性免疫治疗的ctl定向肽。850b - ctl， hla - a33限制性ctl，是从浸润到胃腺癌的T细胞中新建立的。通过表达克隆技术，鉴定出IEX-1和Ran蛋白为850B-CTL特异性识别的肿瘤特异性抗原。这两种蛋白被认为与癌细胞的增殖有关，并在大多数癌细胞系和组织中高度表达。来自IEX-1或Ran的肽被850b -CTL识别，可以诱导CD8^+肽特异性CTL反应，对HLA- a33 ^+胃癌患者和其他上皮性癌症患者的肿瘤细胞，但不能以HLA- i类限制的方式来自健康供体。这些抗原肽可能是针对HLA-A33^+胃癌和其他上皮性癌症的基于肽的特异性免疫治疗的有力候选者。少

1.The aim of this project was to identify tumor-specific antigens that induce humoral responses in pancreatic cancer patients by proteomic approach. Aliquots of solubilized proteins from pancreatic cancer cell lines were subjected to two-dimensional PAGE, followed by Western blot analysis with sera from 5 pancreatic cancer patients and 5 healthy subjects. The spots detected only in cancer patients were analyzed by mass spectrometry to identify the antigens recognized by tumor-specific autoantibodies. Unfortunately, although I tried several experimental conditions, I could not get valid and reproducible results by this approach. Therefore, I decided to modify the approach. Briefly, aliquots of solubilized proteins from cancer cell lines were subjected to immunoprecipitation with autoantibodies purified from pancreatic cancer patients and healthy subjects, followed by two-dimensional PAGE and mass spectrometry. Work is now in progress to identify novel tumor antigens that could be potent … More candidates for specific immunotherapy against pancreatic cancer patients.2.Peptide-based vaccine therapy, which is designed to elicit T-cell immunity against tumors, is an attractive approach for the treatment of cancer patients. We tried to identify CTL-directed peptides for antigen-specific immunotherapy. 850B-CTLs, HLA-A33-restricted CTLs, were newly established from T cells infiltrating into gastric adenocarcinoma. By expression-cloning technique, two proteins, IEX-1 and Ran, were identified as tumor-specific antigens which were specifically recognized by the 850B-CTL. Both proteins are suggested to be involved in the proliferation of cancer cells and highly expressed in most cancer cell lines and tissues. Peptides derived from IEX-1 or Ran, which were recognized by the 850B-CTLs, could induce CD8^+ peptide-specific CTL reaction to tumor cells from HLA-A33^+ gastric cancer patients and other epithelial cancer patients, but not from healthy donors, in an HLA class I-restricted manner. These antigenic peptides could be potent candidates for peptide-based specific immunotherapy against HLA-A33^+ gastric cancer and other epithelial cancers. Less