Micro-Heterogeneity of Antibody Molecules.
Micro-Heterogeneity of Antibody Molecules.
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DOI：
10.1007/978-3-030-76912-3_1
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发表时间：
2021-01-01
影响因子：
--
通讯作者：
Jefferis, Roy
中科院分区：
文献类型：
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作者：
Mimura, Yusuke;Saldova, Radka;Jefferis, Roy
治疗性单克隆抗体（mab）主要是IgG类抗体，是一种高效的生物药物，适用于广泛的临床适应症。全长IgG单克隆抗体是一种大蛋白，在生物合成、纯化或储存过程中会经历多次翻译后修饰（PTMs），导致微异质性。在非人类细胞系中生产重组单克隆抗体可能会导致结构保真度的丧失，并产生具有改变稳定性、生物活性和/或免疫原性潜力的变体。此外，即使是完全人类治疗性单克隆抗体也具有独特的特异性，通过设计，因此具有独特的结构；因此，结构元素可能被近亲繁殖人群中的个体识别为非自我，从而引发抗治疗/抗药物抗体（ATA/ADA）反应。因此，监管机构要求使用最先进的正交分析技术全面表征潜在的单抗药物产品的结构；PTM概要文件可以为药品定义一组关键质量属性（cqa），这些属性必须在药品的整个生命周期内保持，通过设计参数采用质量。IgG-Fc在每条重链Asn297处的糖基化是一种确定的CQA，因为它的存在和精细结构对疗效和安全性有深远的影响。血清来源的IgG的糖型谱是高度异质性的，而在体外哺乳动物细胞中产生的单克隆抗体的异质性较小，可以根据所采用的细胞系和所采用的培养条件进行“编排”。因此，为获得监管机构批准的原料药而建立的特定单抗的总结构和PTM概况必须在药物的整个生命周期内保持。这篇综述概述了我们目前对在单克隆抗体和内源性IgG中检测到的常见PTMs的理解，以及变体的结构属性与其对临床表现的影响之间的关系。
Therapeutic monoclonal antibodies (mAbs) are mostly of the IgG class and constitute highly efficacious biopharmaceuticals for a wide range of clinical indications. Full-length IgG mAbs are large proteins that are subject to multiple posttranslational modifications (PTMs) during biosynthesis, purification, or storage, resulting in micro-heterogeneity. The production of recombinant mAbs in nonhuman cell lines may result in loss of structural fidelity and the generation of variants having altered stability, biological activities, and/or immunogenic potential. Additionally, even fully human therapeutic mAbs are of unique specificity, by design, and, consequently, of unique structure; therefore, structural elements may be recognized as non-self by individuals within an outbred human population to provoke an anti-therapeutic/anti-drug antibody (ATA/ADA) response. Consequently, regulatory authorities require that the structure of a potential mAb drug product is comprehensively characterized employing state-of-the-art orthogonal analytical technologies; the PTM profile may define a set of critical quality attributes (CQAs) for the drug product that must be maintained, employing quality by design parameters, throughout the lifetime of the drug. Glycosylation of IgG-Fc, at Asn297 on each heavy chain, is an established CQA since its presence and fine structure can have a profound impact on efficacy and safety. The glycoform profile of serum-derived IgG is highly heterogeneous while mAbs produced in mammalian cells in vitro is less heterogeneous and can be "orchestrated" depending on the cell line employed and the culture conditions adopted. Thus, the gross structure and PTM profile of a given mAb, established for the drug substance gaining regulatory approval, have to be maintained for the lifespan of the drug. This review outlines our current understanding of common PTMs detected in mAbs and endogenous IgG and the relationship between a variant's structural attribute and its impact on clinical performance.