Hayashi Akimasa, Misumi Kento, Shibahara Junji, Kokudo Norihiro, Kato Yukinari, Fukayama Masashi
Department of Pathology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
Hepato-Biliary-Pancreatic Surgery Division, Department of Surgery, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
Pathol Int. 2016 Oct;66(10):578-582. doi: 10.1111/pin.12459. Epub 2016 Sep 5.
Immunohistochemical analysis using specific antibodies is a useful and convenient method to detect proteins altered by somatic mutations. We previously generated the rat monoclonal antibody MsMab-2, which recognizes isocitrate dehydrogenase (IDH)1 R132L and IDH2 R172M. In the present study, we used an immunohistochemical method to examine MsMab-2 immunoreactivity in 95 cases of intrahepatic cholangiocarcinoma, including five IDH1 R132L and one IDH2 R172M mutant cases confirmed by direct sequencing. Tissue microarray section slides of all IDH1/2-mutant and wild-type cases, as well as whole section slides of IDH1 R132L and IDH2 R172M cases were immunostained using an autostainer. All IDH1 R132L cases showed positive staining for MsMab-2, while other IDH1/2 mutant and IDH1/2 wild-type cases were negative. Tumor cells of the immunopositive cases invariably showed strong reactivity using whole-section slides. We consider immunohistochemical analysis using MsMab-2 to be a useful means of detecting IDH1 R132L. Further analysis of its effectiveness against IDH2 R172M is necessary because of the small sample size in this study.
使用特异性抗体进行免疫组织化学分析是检测由体细胞突变改变的蛋白质的一种有用且便捷的方法。我们之前制备了大鼠单克隆抗体MsMab-2，它可识别异柠檬酸脱氢酶（IDH）1 R132L和IDH2 R172M。在本研究中，我们使用免疫组织化学方法检测了95例肝内胆管癌中MsMab-2的免疫反应性，其中包括5例经直接测序证实的IDH1 R132L突变病例和1例IDH2 R172M突变病例。所有IDH1/2突变型和野生型病例的组织微阵列切片载玻片，以及IDH1 R132L和IDH2 R172M病例的全切片载玻片均使用自动染色仪进行免疫染色。所有IDH1 R132L病例对MsMab-2呈阳性染色，而其他IDH1/2突变型和IDH1/2野生型病例均为阴性。免疫阳性病例的肿瘤细胞在全切片上始终显示出强烈的反应性。我们认为使用MsMab-2进行免疫组织化学分析是检测IDH1 R132L的一种有用方法。由于本研究中的样本量较小，有必要进一步分析其对IDH2 R172M的有效性。
