Budzianowski Jaromir
Przegl Lek. 2015;72(10):567-71.
The Ebola virus disease (EVD), formerly known as a hemorrhagic fever and discovered in 1976, is dangerous, highly infectious disease with very high mortality. There are no licensed therapeutics against EVD, although a range of medicines and therapies are currently being evaluated. During the 2014 Ebola outbreak, an experimental drug named ZMapp was administered on an emergency basis to seven patients of which five were recovered. Currently, since February 2015, ZMapp is tested in clinical trials. ZMapp is a mixture (named a cocktail) of three chimaeric monoclonal antibodies (mAbs) of IgG class, which bind to three different epitopes on Ebola surface glycoprotein (GP). ZMapp was created by systematic selection of antibodies from two other three-component cocktails--MB-003 and ZMab the components of which were produced by rapid transient expression method in tobacco species of Australian origin--Nicotiana benthamiana. The ZMapp antibodies of pharmaceutical grade are manufactured in green-house grown N.benthamiana according to the cGMP (current Good Manufacturing Practice), using RAMP platform (Rapid Antibody Manufacturing Platform) and MagnICON system, which utilizes transient expression by magnifection method using viral vectors delivered to plant tissue by a bacterium--Agrobacterium tumefaciens. The applied glycosylation mutant of N.benthamiana (delta XTFT) synthesizes human-like, biantennary N-glycans, with terminal N-acetylglucoseamine and without typical of plants, immunogenic sugar epitopes-beta1,2-linked xylose and alpha1,3-linked fucose. Due to an absence of fucose on N-glycans attached to the Fc domains, the plant-produced anti-Ebola mAbs elicited significantly stronger antibody-dependent cellular cytotoxicity (ADCC) than the analogous anti-Ebola mAbs with fucosylated (alpha1,6-linked fucose) N-glycans produced in a mammalian CHO cell line--the basic expression system for the industrial production of recombinant therapeutical glycoproteins. As far as a vaccine against Ebola virus disease is considered, so-called Ebola Immunogenic Complex (EIC) consisting of assembled molecules of a humanized IgG mAb--6D8 specific for Ebola GPI with GP1 fused to the C-terminus of the heavy chains, was obtained by transient expression in N. benthamiana.
埃博拉病毒病(EVD),以前称为出血热,于1976年被发现,是一种危险的、传染性很强且死亡率极高的疾病。目前尚无针对埃博拉病毒病的许可治疗方法,不过一系列药物和疗法正在评估中。在2014年埃博拉疫情期间,一种名为ZMapp的实验性药物被紧急用于7名患者,其中5人康复。目前,自2015年2月起,ZMapp正在进行临床试验。ZMapp是一种IgG类的三种嵌合单克隆抗体(mAb)的混合物(称为鸡尾酒),它们与埃博拉病毒表面糖蛋白(GP)上的三个不同表位结合。ZMapp是通过从另外两种三组分鸡尾酒——MB - 003和ZMab中系统筛选抗体而产生的,这两种鸡尾酒的成分是通过在澳大利亚原产的烟草品种——本氏烟草中采用快速瞬时表达方法生产的。药用级的ZMapp抗体是在温室种植的本氏烟草中按照cGMP(现行药品生产质量管理规范)生产的,使用RAMP平台(快速抗体生产平台)和MagnICON系统,该系统利用病毒载体通过根癌农杆菌递送至植物组织的放大感染方法进行瞬时表达。所应用的本氏烟草糖基化突变体(delta XTFT)合成与人相似的双天线N -聚糖,其末端为N -乙酰葡糖胺,且没有植物特有的具有免疫原性的糖表位——β1,2 -连接的木糖和α1,3 -连接的岩藻糖。由于附着在Fc结构域上的N -聚糖上没有岩藻糖,植物产生的抗埃博拉mAb比在哺乳动物CHO细胞系(重组治疗性糖蛋白工业生产的基本表达系统)中产生的具有岩藻糖基化(α1,6 -连接的岩藻糖)N -聚糖的类似抗埃博拉mAb引发的抗体依赖性细胞毒性(ADCC)明显更强。就针对埃博拉病毒病的疫苗而言,通过在本氏烟草中瞬时表达获得了所谓的埃博拉免疫原性复合物(EIC),它由针对埃博拉糖基磷脂酰肌醇(GPI)且GP1融合到重链C末端的人源化IgG mAb——6D8的组装分子组成。