Purification Process Development, Amgen Inc., 1201 Amgen Court West, Seattle, Washington 98119, USA.
Biotechnol Bioeng. 2012 Jan;109(1):157-65. doi: 10.1002/bit.23300. Epub 2011 Aug 23.
One measure taken to ensure safety of biotherapeutics produced in mammalian cells is to demonstrate the clearance of potential viral contaminants by downstream purification processes. This paper provides evidence that cation exchange chromatography (CEX), a widely used polishing step for monoclonal antibody (mAb) production, can effectively and reproducibly remove xMuLV, a retrovirus used as a model of non-infectious retrovirus-like particles found in Chinese hamster ovary cells. The dominant mechanism for xMuLV clearance by the strong cation exchanger, Fractogel SO ₃⁻, is by retention of the virus via adsorption instead of inactivation. Experimental data defining the design space for effective xMuLV removal by Fractogel SO ₃⁻ with respect to operational pH, elution ionic strength, loading, and load/equilibration buffer ionic strength are provided. Additionally, xMuLV is able to bind to other CEX resins, such as Fractogel COO⁻ and SP Sepharose Fast Flow, suggesting that this phenomenon is not restricted to one type of CEX resin. Taken together, the data indicate that CEX chromatography can be a robust and reproducible removal step for the model retrovirus xMuLV.
一种确保哺乳动物细胞生产的治疗性生物制品安全性的措施是证明下游纯化工艺能够清除潜在的病毒污染物。本文提供的证据表明，阳离子交换层析（CEX）是单克隆抗体（mAb）生产中广泛使用的一种精制步骤，可以有效地、可重复地去除 xMuLV，xMuLV 是一种逆转录病毒，可作为中国仓鼠卵巢细胞中发现的无感染性逆转录病毒样颗粒的模型。强阳离子交换剂 Fractogel SO₃⁻ 清除 xMuLV 的主要机制是通过吸附而非失活来保留病毒。提供了关于有效去除 Fractogel SO₃⁻ 中 xMuLV 的设计空间的实验数据，这些数据与操作 pH、洗脱离子强度、上样、上样/平衡缓冲液离子强度有关。此外，xMuLV 能够结合到其他 CEX 树脂上，如 Fractogel COO⁻ 和 SP Sepharose Fast Flow，这表明这种现象不限于一种 CEX 树脂。综上所述，这些数据表明 CEX 层析可以作为模型逆转录病毒 xMuLV 的一种稳健且可重复的去除步骤。
