Hiyamuta S, Takeichi N
Central Research Laboratories, Idemitsu Kosan Co., Ltd., Chiba, Japan.
Biochem Biophys Res Commun. 1993 Dec 30;197(3):1140-5. doi: 10.1006/bbrc.1993.2596.
Recently it was found that the clinical features of the LEC rat closely resemble those of human Wilson's disease. One of the characteristics of the animal is low levels of serum ceruloplasmin. Therefore, by using LEC rats, we attempted to define molecular basis of the deficiency in active site of ceruloplasmin in Wilson's disease patients. We made 3 monoclonal antibodies, ID2 against active site of ceruloplasmin, ID1 against inactive site of ceruloplasmin, and the remaining one against metallothionein. Using these monoclonal antibodies, we examined immunohistochemical stainings of LEC rat liver tissues, and compared them with those of LEA rats, as a control. ID1 stained the hepatocytes of both LEA and LEC rats, whereas ID2 stained LEA rat hepatocytes only. The results indicated that the ceruloplasmin secreted by LEC rat hepatocytes is mostly in inactive form. The antibody against metallothionein stained LEA rat hepatocytes only. This finding may also indicate that LEC rat hepatocytes express less amount of metallothionein than those of LEA rats.
最近发现，LEC大鼠的临床特征与人类威尔逊氏病极为相似。该动物的特征之一是血清铜蓝蛋白水平较低。因此，我们利用LEC大鼠试图确定威尔逊氏病患者铜蓝蛋白活性位点缺乏的分子基础。我们制备了3种单克隆抗体，ID2针对铜蓝蛋白的活性位点，ID1针对铜蓝蛋白的非活性位点，另一种针对金属硫蛋白。利用这些单克隆抗体，我们检测了LEC大鼠肝脏组织的免疫组织化学染色，并将其与作为对照的LEA大鼠的染色结果进行比较。ID1对LEA和LEC大鼠的肝细胞均有染色，而ID2仅对LEA大鼠的肝细胞有染色。结果表明，LEC大鼠肝细胞分泌的铜蓝蛋白大多为非活性形式。抗金属硫蛋白抗体仅对LEA大鼠的肝细胞有染色。这一发现也可能表明，LEC大鼠肝细胞表达的金属硫蛋白比LEA大鼠的少。
