@misc{oai:repo.qst.go.jp:00069460, author = {Sogawa, Chizuru and Tsuji, Atsushi and Sugyou, Aya and Sudou, Hitomi and Furukawa, Takako and Koizumi, Mitsuru and Harada, Yoshinobu and Saga, Tsuneo and et.al and 曽川 千鶴 and 辻 厚至 and 須尭 綾 and 須藤 仁美 and 古川 高子 and 小泉 満 and 原田 良信 and 佐賀 恒夫}, month = {Sep}, note = {Mesothelioma is an aggressive tumor arising from serosal surfaces of the pleura and peritoneum closely related to asbestos exposure. This is a rare tumor, but the incidence is increasing worldwide over the next several decades because of high consumption of asbestos. Although the prognosis of patients with current treatments remains poor, that of patients at an early stage has been reported to be improved. Thus, the diagnosis at the early stage of mesothelioma is necessary for the better prognosis. However, current diagnostic modalities including FDG-PET are difficult to detect the early stage of mesothelioma, and it is essential to develop a new diagnostic method for detection at the early stage. The ERC/Mesothelin (ERC) is a cell surface glycoprotein and is strongly expressed in epithelioid subtype of mesothelioma. The primary product of ERC is a 71-kDa precursor protein, which is cleaved into a 40-kDa C-terminal fragment that remains membrane-bound and a 31-kDa N-terminal fragment that is secreted into the blood. Since the antibody against the C-terminal fragment is very useful for distinguishing pleural mesotheliomas from adenocarcinomas and squamous cell carcinomas of the lung by immunohistochemistry, the radiolabeled antibody recognizing C-terminal fragment could be used for in vivo imaging of ERC-positive mesotheliomas. In this study, we radiolabeled anti-ERC antibody with 125I and 111In, and performed cell binding, competitive inhibition and internalization assays in vitro using a human mesothelioma cell line, H226, highly expressing ERC primarily localized to the cell membrane. We also performed biodistribution and SPECT imaging in vivo using tumor-bearing mice. These results showed that the radiolabeled antibody specifically bound to ERC expressing cells and were weakly internalized, and the 111In-labeled antibody highly accumulated in the xenografted tumor, which was readily visualized by SPECT. The radiolabeled anti-ERC antibody would be useful for the PET/SPECT imaging of malignant mesothelioma., World Molecular Imaging Congress}, title = {Development of anti-ERC/mesothelin antibody probe for PET/SPECT imaging of Malignant Mesothelioma}, year = {2008} }