Highly Viscous Antibody Solutions Are a Consequence of Network Formation Caused by Domain-Domain Electrostatic Complementarities: Insights from Coarse-Grained Simulations
Highly Viscous Antibody Solutions Are a Consequence of Network Formation Caused by Domain-Domain Electrostatic Complementarities: Insights from Coarse-Grained Simulations
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DOI：
10.1021/mp500485w
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发表时间：
2015-01-01
影响因子：
4.9
通讯作者：
Singh, Satish K.
中科院分区：
文献类型：
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作者：
Buck, Patrick M.;Chaudhri, Anuj;Singh, Satish K.
在高于100 mg/mL的浓度下形成高粘性溶液的治疗性单克隆抗体（mAb）候选物可导致生物加工、制剂开发和皮下药物递送方面的挑战。具有浓度依赖性高粘度的mAb的早期研究表明，具有带负电荷的Fv区的mAb具有偶极样性质，其增加了可逆自缔合的可能性。这表明，弱的静电分子间相互作用可以形成瞬时抗体网络，参与抵抗剪切应力下的溶液变形。在这里，这个假设是通过参数化的粗粒度（CG）模型的抗体使用的结构域电荷从四个不同的单克隆抗体，其浓度依赖性的粘度行为先前确定。在几种浓度下对这四种CG mAb进行多拷贝分子动力学模拟，以了解表面电荷对质量扩散率、成对相互作用和静电网络形成的影响。从模拟计算的扩散系数与实验确定的粘度为所有四个单克隆抗体的定性协议。接触分析显示，在本研究中，两种mAb的成对相互作用的总体数量更大，存在高浓度粘度问题。此外，使用平衡溶液轨迹，具有高浓度粘度问题的两种mAb定量地形成比其他mAb更多的静电网络特征。这些网络特征的数量随浓度的变化与抗体结构域之间的静电互补性形成的成对相互作用的数量有关。因此，由结构域-结构域静电互补性引起的瞬时抗体网络形成是本研究中mAb高浓度粘度的最可能来源。
Therapeutic monoclonal antibody (mAb) candidates that form highly viscous solutions at concentrations above 100 mg/mL can lead to challenges in bioprocessing, formulation development, and subcutaneous drug delivery. Earlier studies of mAbs with concentration-dependent high viscosity have indicated that mAbs with negatively charged Fv regions have a dipole-like quality that increases the likelihood of reversible self-association. This suggests that weak electrostatic intermolecular interactions can form transient antibody networks that participate in resistance to solution deformation under shear stress. Here this hypothesis is explored by parametrizing a coarse-grained (CG) model of an antibody using the domain charges from four different mAbs that have had their concentration-dependent viscosity behaviors previously determined. Multicopy molecular dynamics simulations were performed for these four CG mAbs at several concentrations to understand the effect of surface charge on mass diffusivity, pairwise interactions, and electrostatic network formation. Diffusion coefficients computed from simulations were in qualitative agreement with experimentally determined viscosities for all four mAbs. Contact analysis revealed an overall greater number of pairwise interactions for the two mAbs in this study with high concentration viscosity issues. Further, using equilibrated solution trajectories, the two mAbs with high concentration viscosity issues quantitatively formed more features of an electrostatic network than the other mAbs. The change in the number of these network features as a function of concentration is related to the number of pairwise interactions formed by electrostatic complementarities between antibody domains. Thus, transient antibody network formation caused by domain-domain electrostatic complementarities is the most probable origin of high concentration viscosity for mAbs in this study.