Ning Li, Pan Bo, Zhao Yu-pei, Liao Quan, Zhang Tai-ping, Chen Ge, Wang Wei-bin, Yang Ying-chi
Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100730, China.
Zhonghua Wai Ke Za Zhi. 2007 Jan 1;45(1):34-8.
To screen and identify the immunogenic membrane antigens in human pancreatic cancer for early diagnosis.
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.
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.
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.
筛选并鉴定人胰腺癌中的免疫原性膜抗原用于早期诊断。
从胰腺癌细胞系中提取膜蛋白，采用双向电泳（2-DE）进行分离。两张平行的2-DE凝胶中的一张进行染色，另一张进行免疫印迹。从临床收集的胰腺癌患者血清中纯化得到的血清IgG用作免疫印迹的一抗。通过基质辅助激光解吸电离飞行时间质谱（MALDI-TOF）和肽质量指纹图谱（PMF）匹配鉴定免疫印迹的阳性点，然后通过生物信息学方法进行评估。通过逆转录聚合酶链反应（RT-PCR）和免疫组织化学分别在细胞系和组织中进一步验证候选膜抗原。
癌患者血清IgG与混合膜蛋白的免疫印迹显示8个阳性点。这些点经MALDI和PMF鉴定为：电压依赖性阴离子通道1（VDAC-1）、电压依赖性阴离子通道2（VDAC-2）、卷曲螺旋结构域蛋白3（CHCHD3）、信号淋巴细胞激活分子家族成员2（SLP-2）和外膜转位酶40（TOM40）。RT-PCR表明这些膜抗原在几种胰腺癌细胞系中表达。免疫组织化学显示癌组织中SLP-2明显过表达。
VDAC-1、VDAC-2、CHCHD3、SLP-2和TOM40是胰腺癌新的候选免疫原性膜抗原。这些膜抗原随后可在高危人群中进行检测以用于胰腺癌的早期诊断。
