Natsume Akito, Wakitani Masako, Yamane-Ohnuki Naoko, Shoji-Hosaka Emi, Niwa Rinpei, Uchida Kazuhisa, Satoh Mitsuo, Shitara Kenya
Department of Antibody Research, Pharmaceutical Research Center, Kyowa Hakko Kogyo Co., Ltd., 3-6-6 Asahi-machi, Machida-shi, Tokyo 194-8533, Japan.
J Immunol Methods. 2005 Nov 30;306(1-2):93-103. doi: 10.1016/j.jim.2005.07.025. Epub 2005 Oct 3.
Fucose removal from complex-type oligosaccharide of human IgG1-type antibody results in a great enhancement of antibody-dependent cellular cytotoxicity (ADCC). The aim of this study was to clarify the effect of fucose removal on effector functions of a single-gene-encoded antibody with an scFv used as the binding domain. We generated both a fucose-negative anti-tumor associated glycoprotein (TAG)-72 scFv-Fc using alpha-1,6-fucosyltransferase knock-out CHO cells and a highly fucosylated scFv-Fc from parental CHO cells. Expression, assembly and antigen binding activity of the scFv-Fcs were not influenced by fucose removal. The scFv-Fc lacking fucose exhibited significantly more potent FcgammaRIIIa binding and ADCC compared to highly fucosylated scFv-Fc. These results prove that ADCC enhancement by fucose-removal is effective in not only whole IgG1, but also scFv-Fc, and thus increases the potential of Fc-fusion proteins as therapeutic candidates.
从人IgG1型抗体的复合型寡糖中去除岩藻糖可极大增强抗体依赖性细胞毒性（ADCC）。本研究的目的是阐明去除岩藻糖对以单链抗体片段（scFv）作为结合域的单基因编码抗体效应功能的影响。我们利用α-1,6-岩藻糖基转移酶基因敲除的中国仓鼠卵巢（CHO）细胞生成了无岩藻糖的抗肿瘤相关糖蛋白（TAG）-72 scFv-Fc，以及来自亲本CHO细胞的高岩藻糖基化scFv-Fc。scFv-Fc的表达、组装和抗原结合活性不受岩藻糖去除的影响。与高岩藻糖基化的scFv-Fc相比，缺乏岩藻糖的scFv-Fc表现出显著更强的FcγRIIIa结合能力和ADCC。这些结果证明，去除岩藻糖增强ADCC不仅对完整的IgG1有效，对scFv-Fc也有效，从而增加了Fc融合蛋白作为治疗候选药物的潜力。
