TRIFLUOROACETYLATED 62-KDA PROTEIN AS POSSIBLE IMMUNOGEN IN HALOTHANE HEPATITIS

氟烷型肝炎患者的血清已被证明含有 与几种三氟乙酰化蛋白(100 kDa， 80 kDa、63 kDa、59 kDa、57 kDa和54 kDa) 氟烷治疗的大鼠。这些发现表明，类似的 三氟乙酰化蛋白是免疫原，负责 患者抗体的形成以及随后的可能 肝炎的发展。今年一个几乎全长的cdna克隆 从Lambda gt11大鼠肝脏cDNA文库中分离到63 kDa蛋白。 根据该克隆的编码序列和 纯化蛋白的N末端和几个内肽，分子量为63 kDa 已被鉴定为钙网蛋白。大鼠基因组DNA的制备 用包含克隆的开放阅读片段的片段探测肝脏 框架。发现与单个基因组区域有很强的同源性，但 与延长放射自显影后检测到的第二个区域同源， 这表明63 kDa蛋白不是多基因家族的一部分。 抗63 kDa抗体在几种组织中的免疫印迹 这种蛋白质存在于身体的所有组织中，其中最高的 在肝脏、睾丸和脂肪组织中的浓度。钙网织蛋白 是一种非肌肉组织内质网的钙结合蛋白 细胞和肌细胞中的肌浆网。钙网硬蛋白是 被认为通过起到储存钙离子的作用而在钙稳态中起作用 钙的储存库。因为目前的研究表明，钙网织蛋白 可以作为药物的活性代谢物的靶点，这就提高了 这种蛋白质的钙结合能力可能是 被药物改变并因此发挥作用的毒性不产生 不仅用氟烷，也用其他药物。

Sera from halothane hepatitis patients have been shown to contain antibodies that react with several trifluoroacetylated proteins (100 kDa, 80 kDa, 63 kDa, 59 kDa, 57 kDa, and 54 kDa) purified from the livers of halothane treated rats. These findings suggest that similar trifluoroacetylated proteins are the immunogens responsible for the formation of the patients' antibodies and perhaps the subsequent development of hepatitis. This year a nearly full-length cDNA clone of the 63 kDa protein has been isolated from a Lambda gt11 rat liver cDNA library. Based upon the encoded sequence of this clone and the sequences of the N-terminal and several internal peptides of the purified protein, 63 kDa has been identified as calreticulin. Genomic DNA preparations from rat liver were probed with a fragment encompassing the cloned open reading frame. Strong homology was found to a single genomic region, with limited homology to a second region detected after prolonged autoradiography, indicating that the 63 kDa protein is not part of a multi-gene family. Immunoblotting of several tissues with the anti-63 kDa antibody indicated that the protein was present in all tissues of body, with highest concentrations being in the liver, testes, and adipose tissue. Calreticulin is a calcium binding protein of the endoplasmic reticulum in non-muscle cells and the sarcoplasmic reticulum in muscle cells. Calreticulin is thought to have a role in calcium homeostasis by acting as a storage reservoir of calcium. Since the present study has shown that calreticulin can be a target of the reactive metabolites of drugs, this raises the possibility that the calcium binding capacity of this protein can be altered by drugs and as a result play a role in the toxicity produced not only by halothane, but also by other drugs.