For IgG-like bispecific antibodies (bsAbs) whose construction involves sequence engineering to promote desired heavy chain-light chain pairing, ¾ antibody (antibody lacking one light chain) is a frequent byproduct during their recombinant production. As this byproduct shares high similarity in physicochemical properties with the target bsAb, its removal poses a challenge to downstream purification. Capto L is an affinity resin based on Protein L, which binds to the variable region of kappa light chain without interfering with the antigen binding site. In this work, we demonstrated that Capto L provides a convenient means for separating ¾ antibody from the bsAb product.

对于其构建涉及序列工程以促进所需的重链-轻链配对的IgG样双特异性抗体（bsAbs），3/4抗体（缺乏一个轻链的抗体）是其重组生产中的常见副产物。由于该副产物在理化特性上与目标bsAb具有高度相似性，因此其去除对下游纯化提出了挑战。Capto L是一种基于蛋白质L的亲和树脂，可与κ轻链可变区结合而不会干扰抗原结合位点。在这项工作中，我们证明了Capto L为从bsAb产物中分离出¾抗体提供了一种方便的方法。