The advantage of high pH eluting Protein A resins over their regular counterparts in aggregate and host cell protein clearance

Abstract

Protein A affinity chromatography is the most well-established method and gold standard for antibody purification. Typically, low pH (i.e., 3.0–3.5) is required for elution of bound antibodies from a Protein A column. However, for acid-sensitive antibodies, this low pH condition can trigger severe aggregation. Therefore, alternative Protein A resins supporting mild elution are highly desirable. To meet this need, recently Purolite and Cytiva both developed high pH eluting Protein A resins (i.e., Jetted A50 HipH and MabSelect mild elution, respectively). We previously showed that Jetted A50 HipH not only supports mild pH elution but also exhibits improved aggregate separation capability. In the current work, with four case studies, we compared the above-mentioned two high pH eluting Protein A resins with their regular counterparts (i.e., Jetted A50 and MabSelect SuRe LX, respectively) and demonstrated that the two special Protein A resins provided much better aggregate removal and host cell protein (HCP) clearance. Thus, in addition to supporting mild elution, the two high pH eluting Protein A resins also have an edge in terms of impurity clearance.