THYROTROPIN BIOSYNTHESIS, GLYCOSYLATION, ACTION--RECOMBINANT TSH CLINICAL TRIALS

重组促甲状腺激素用来刺激体内放射性碘摄取 甲状腺癌患者是通过新的方法产生的 α-和HTSH-β基因导入中国仓鼠卵巢的研究 细胞。也可利用大型生物反应器生产的产品 作为一个中空纤维生物反应器，我们已经能够提纯数百个 毫克的这种产品。重组促甲状腺激素的末端唾液酸化 测定体外和体内生物活性以及清除率。 重组TSH的碳水化合物结构已被表征 细节与垂体型TSH不同。糖结构在蛋白质合成中的作用 生物活性也通过酶促脱糖作用得到了阐明。 定点诱变及其新型重组菌株的生产 杂交种已经被用来开发新的促甲状腺激素类似物，延长了一半 生活。我们还开发了TSH的竞争性拮抗剂，它将 用于治疗甲状腺功能亢进症和甲状腺功能亢进症患者 癌症。利用重组TSH结构的同源模建，我们 已经能够基于理性原则设计超级激动剂。 这种超激动剂在各种体外和体内试验中都是有效的。 并包括其他糖蛋白激素，如促性腺激素。 我们已经完成了重组TSH的1-3期临床试验 与其他12个医疗中心合作。在增加了一个 验证性试验，该药应被批准用于诊断 甲状腺癌。

Recombinant thyrotropin whih is used to stimulate radioiodine uptake in patients with thyroid cancer has been produced by novel methods of transfection of alpha and hTSH beta minigenes into Chinese hamster ovary cells. Utilizing products produced ina large scale bioreactor as well as a hollow fiber bioreactor, we have been able to purify several hundred milligrams of this product. Terminal sialylation of recombinant TSH determines in vitro and in vivo bioactivity as well as clearance rate. The carbohydrate structure of recombinant TSH hs been characterized in detail and differs from pituitary TSH. The role of sugar structures in bioactivity has also been clarified by enzymatic deglycosylation. Site-directed mutagenesis as well as production of novel recombinant hybrids has been used to develop new TSH analogs with prolonged half life. We have also developed competitive antagonists of TSH which will be useful in treatment of patients with hyperthyroidism and thyroid cancer. Using homology modeling of the structure of recombinant TSH, we have been able to design superagonists based on rational principles. Such superagonists are active in a variety of in vitro and in vivo assays and include other glycoprotein hormones such as gonadotropins. We have completed phase 1-3 clinical trials of recombinant TSH in collaboration with 12 other medical centers. After one additional confirmatory trial, this drug should be approved for the diagnosis of thyroid cancer.