Sudo Y, Itoh M
Third Department of Internal Medicine, Hamamatsu University School of Medicine, Japan.
Diabetes Res Clin Pract. 1994 Mar;23(2):69-76. doi: 10.1016/0168-8227(94)90013-2.
To study the target antigens of the islet cell cytoplasmic antibodies (ICA), we tried to make a monoclonal islet cell antibody. We made a monoclonal antibody 14A20 (IgM, kappa) that reacted strongly with Wistar and BB rat islet cells and weakly with pancreatic acinar cells. The immunoreactivity of the 14A20 was also found to react extensively in neuroendocrine cells. Immunostaining showed a granular pattern in both neurons and islet cells. Chemical and enzymic studies revealed that the antigen has the property of a protein. We compared immunoreactivity of the monoclonal antibody 14A20 with anti-insulin, -glucagon or -somatostatin antibodies. The antigen recognized by the monoclonal antibody 14A20 was equally present in the alpha, beta, and delta cells of islet, which mimicked the immunoreactivity of the ICA in the pancreas. The recognized protein had a relative molecular weight of 220,000, indicating that it is different from the previously identified target antigen of the ICA.
为了研究胰岛细胞胞浆抗体（ICA）的靶抗原，我们尝试制备一种单克隆胰岛细胞抗体。我们制备了一种单克隆抗体14A20（IgM，κ链），它与Wistar大鼠和BB大鼠的胰岛细胞强烈反应，与胰腺腺泡细胞反应较弱。还发现14A20的免疫反应性在神经内分泌细胞中广泛存在。免疫染色显示神经元和胰岛细胞中均呈颗粒状模式。化学和酶学研究表明该抗原具有蛋白质特性。我们比较了单克隆抗体14A20与抗胰岛素、抗胰高血糖素或抗生长抑素抗体的免疫反应性。单克隆抗体14A20识别的抗原在胰岛的α、β和δ细胞中均有同等表达，这与胰腺中ICA的免疫反应性相似。所识别的蛋白质相对分子质量为220,000，表明它与先前鉴定的ICA靶抗原不同。
