Effect of PEGylation on the solution conformation of antibody fragments
Effect of PEGylation on the solution conformation of antibody fragments
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DOI：
10.1002/jps.21170
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发表时间：
2008-06-01
影响因子：
3.8
通讯作者：
Rowe, Arthur J.
中科院分区：
文献类型：
--
作者：
Lu, Yanling;Harding, Stephen E.;Rowe, Arthur J.
聚乙二醇（PEG）与治疗性抗体片段的共价附着已被发现能有效地延长蛋白质分子在体内的半衰期。在这项研究中，分析超离心（AUC）结合小角x射线散射（SAXS）已应用于许多抗体片段及其各自的聚乙二醇化偶联物。尽管由于附着20-40 kDa的PEG片段而大大增加了分子量，但聚乙二醇化的偶联物的沉降系数s比亲本抗体片段小，这是由于摩擦比f/f(o)显著增加（从类似于1.3到2.3-2.8）：偶联物的溶液流体动力学性质明显由PEG片段主导（f/f(o)类似于3.0）。高r值（粒子内散射中心的分离）的SAXS数据强化了这一观察结果，该r值似乎由复合物的PEG部分主导。相比之下，低r值下的SAXS数据表明，PEGylation后蛋白质片段本身没有明显的构象变化。PEGylation位点在偶联物中的位置被确定，并且发现与偶联化学的预期一致。2007 Wiley-Liss, Inc.和美国药剂师协会。
Covalent attachment of poly(ethylene glycol) (PEG) to therapeutic antibody fragments has been found effective in prolonging the half-life of the protein molecule in vivo. In this study analytical ultracentrifugation (AUC) in combination with small angle X-ray scattering (SAXS) has been applied to a number of antibody fragments and to their respective PEGylated conjugates. Despite the large increase in molecular weight due to the attachment of a 20-40 kDa PEG moiety, the PEGylated conjugates have smaller sedimentation coefficients, s, than their parent antibody fragments, due to a significant increase in frictional ratio f/f(o) (from similar to 1.3 to 2.3-2.8): the solution hydrodynamic properties of the conjugates are clearly dominated by the PEG moiety (f/f(o) similar to 3.0). This observation is reinforced by SAXS data at high values of r (separation of scattering centres within a particle) that appear dominated by the PEG part of the complex. By contrast, SAXS data at low values of r suggest that there are no significant conformational changes of the protein moiety itself after PEGylation The location of the PEGylation site within the conjugate was identified, and found to be consistent with expectation from the conjugation chemistry. 0 2007 Wiley-Liss, Inc. and the American Pharmacists Association.