In general, purification of bispecific antibody (bsAb) is more challenging than that of monospecific antibody due to the increased complexity in byproduct profile. Like in the case of monospecific antibody purification, immunoglobulin-binding protein-based affinity chromatography is an indispensable tool for bsAb purification. For example, Protein A affinity chromatography has been widely used to capture Fc-containing bsAbs whereas other affinity media such as Protein L and KappaSelect, which bind kappa light chain, are used to capture bsAbs that do not contain a Protein A-binding site. In fact, affinity chromatography also possesses the capability of removing certain product-related impurities in bsAb purification when it is conducted with suitable medium and under appropriate conditions. Fully exploring the potential of affinity chromatography in bsAb purification to achieve both product capture and byproduct removal is highly desirable, as this can greatly alleviate the purification burden on subsequent polishing steps and hence improves the overall robustness of the downstream process. This article briefly reviews the byproduct clearance potential of several commonly used affinity media under relevant bsAb purification scenarios.

一般来说，由于副产物谱的复杂性增加，双特异性抗体 (bsAb) 的纯化比单特异性抗体的纯化更具挑战性。与单特异性抗体纯化一样，基于免疫球蛋白结合蛋白的亲和层析是 bsAb 纯化不可或缺的工具。例如，Protein A 亲和层析已被广泛用于捕获含 Fc 的 bsAb，而其他亲和介质，例如 Protein L 和 KappaSelect，可结合 kappa 轻链，用于捕获不包含 Protein A 结合位点的 bsAb。事实上，亲和层析也具有去除bsAb纯化中某些与产物相关的杂质的能力，当它在合适的介质和条件下进行时。充分探索亲和色谱在 bsAb 纯化中实现产物捕获和副产物去除的潜力是非常可取的，因为这可以大大减轻后续精制步骤的纯化负担，从而提高下游过程的整体稳健性。本文简要回顾了相关 bsAb 纯化场景下几种常用亲和介质的副产物清除潜力。