Immunohistochemistry using monoclonal antibody MsMab-2 is useful to detect IDH1 R132L in intrahepatic cholangiocarcinoma.
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.
Department of Pathology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
Akimasa
A
Hayashi
Department of Pathology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
Kento
K
Misumi
Department of Pathology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan. jshiba-tky@umin.ac.jp.
Junji
J
Shibahara
Hepato-Biliary-Pancreatic Surgery Division, Department of Surgery, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
Norihiro
N
Kokudo
Department of Regional Innovation, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan.
Yukinari
Y
Kato
Department of Pathology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
Masashi
M
Fukayama
D000911:Antibodies, Monoclonal; D001650:Bile Duct Neoplasms / Q000235:genetics* / Q000473:pathology; D014408:Biomarkers, Tumor / Q000032:analysis*; D018281:Cholangiocarcinoma / Q000235:genetics* / Q000473:pathology; D004252:DNA Mutational Analysis / Q000379:methods*; D006801:Humans; D007150:Immunohistochemistry; D007521:Isocitrate Dehydrogenase / Q000235:genetics*; D009154:Mutation; D046888:Tissue Array Analysis
D000911:Antibodies, Monoclonal; D014408:Biomarkers, Tumor; D007521:Isocitrate Dehydrogenase; C543588:IDH1 protein, human
IDH; MsMab-2; immunohistochemistry; intrahepatic cholangiocarcinoma