中文摘要：

目的筛查具有早期诊断价值的人胰腺癌相关膜抗原。方法采用膜生物学技术抽提多株胰腺癌细胞的膜蛋白；双向聚丙烯酰胺凝胶电泳（2-DE）分离膜蛋白，将其转移至PVDF膜上；利用纯化的胰腺癌患者血清IgG与分离的膜蛋白进行免疫印迹杂交，比对膜蛋白2-DE图谱，筛查胰腺癌特异的免疫杂交阳性斑点；MALDI—TOF质谱鉴定杂交阳性斑点；采用RT—PCR技术检测膜抗原基因在多株胰腺癌细胞中的表达；利用免疫组化染色技术检测膜抗原在人胰腺癌组织中的表达情况。结果成功提取了胰腺癌细胞株的膜蛋白；经比对膜蛋白2-DE图谱，筛查出免疫杂交阳性斑点；经MALDI—TOF质谱鉴定，免疫杂交阳性点分别为VDAC-2、VDAC-1、CHCHD3、SLP-2、TOM40；RT—PCR结果显示上述膜抗原基因在多株胰腺癌细胞中均有表达；免疫组织化学染色证实，SLP-2在胰腺癌组织中呈现显著高表达。结论SLP-2、VDAC-1、VDAC-2、CHCHD3、TOM40是新发现的与人胰腺癌相关的具有免疫原性的膜抗原，利用这些膜抗原检测胰腺癌高危人群外周血中的特异性自身抗体将有助于实现胰腺癌的早期诊断。

英文摘要：

Objective To screen and identify the immunogenic membrane antigens in human pancreatic cancer for early diagnosis. Methods Membrane protein was extracted from pancreatic cancer cell lines and separated by using 2-DE. One of the two parallel 2-DE gels went for staining while the other underwent immunoblot. Serum IgG, which was purified from clinically collected sera of pancreatic cancer patients, was used as the primary antibodies for the immunoblot. Positive dots of immunoblot were identified by MALDI-TOF mass spectrometry and PMF matching, and then evaluated by bio-informatics methods. The candidate membrane antigens were further validated respectively in cell lines and tissues by RT-PCR and immunohistochemistry. Results The immunoblot of mixed membrane protein with serum IgG from cancer patients showed eight positive dots. These dots were identified with MALDI and PMF as： VDAC-1, VDAC- 2, CHCHD3, SLP-2 and TOM40. RT-PCR showed that these membrane antigens were expressed in several pancreatic cancer cell lines. Immunohistochemistry showed prominent SLP-2 over expression in cancer tissue. Conclusions VDAC-1, VDAC-2, CHCHD3, SLP-2, and TOM40 are the new candidate immunogenic membrane antigens of pancreatic cancer. These membrane antigens can be subsequently tested in high dangerous population for early diagnosis of pancreatic cancer.