Department of Protein Analytical Chemistry, Genentech, USA.
J Chromatogr A. 2011 Aug 5;1218(31):5079-86. doi: 10.1016/j.chroma.2011.05.061. Epub 2011 May 27.
In this report, we have demonstrated the isolation and enrichment of charge variants of a monoclonal antibody IgG1 using cation exchange displacement chromatography. We successfully achieved the separation of acidic, main and basic charge variants with high recovery (>70%) and purity (>90%) by using a commercially available stationary phase in conjunction with a commercially available displacer. In addition, we have isolated and enriched a trace methionine-oxidized variant of the monoclonal antibody allowing a secondary means of identification of this variant while providing sufficient enrichment for further analysis, stability tests and potency determination. Further characterization of the displacement trains by SEC indicate the possibility of enrichment of high and low molecular weight species. Glycan analysis of the displacement fractions indicates minimal variation in glycan distribution patterns among a wide spectrum of charge variants. These results provide a case study demonstrating the utility of cation exchange displacement chromatography as a viable approach to isolate and enrich antibody charge variants for enhanced molecular characterization.
在本报告中，我们展示了使用阳离子交换置换色谱法分离和富集单克隆抗体 IgG1 的荷电变异体。我们成功地使用市售的固定相和市售的置换剂，以高回收率（>70%）和高纯度（>90%）分离出酸性、主要和碱性荷电变异体。此外，我们还分离和富集了单克隆抗体的痕量蛋氨酸氧化变异体，为该变异体的鉴定提供了第二种方法，同时为进一步分析、稳定性测试和效力测定提供了足够的富集。SEC 对置换产物的进一步表征表明，高和低分子量物质有可能被富集。置换馏分的聚糖分析表明，在广泛的电荷变异体中，聚糖分布模式的变化很小。这些结果提供了一个案例研究，证明了阳离子交换置换色谱法作为一种可行的方法，用于分离和富集抗体的电荷变异体，以增强分子表征。
