Chen Quan, Toh Phyllicia, Hoi Aina, Xian Mo, Peng Xinying, Yang Yuansheng, Zhang Haibo, Nian Rui, Zhang Wei
Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, CAS Key Laboratory of Biobased Materials, Qingdao 266101, Shandong, China.
Bioprocessing Technology Institute, Agency for Science, Technology and Research (A*STAR), Singapore 138668, Singapore.
Sheng Wu Gong Cheng Xue Bao. 2016 Jun 25;32(6):807-818. doi: 10.13345/j.cjb.160137.
Therapeutic monoclonal antibodies become the major product class within the biopharmaceutical market. Protein A as the first capture step is still dominant in current platforms for purification of monoclonal antibodies. In this study, we developed a new antibody harvest process that incorporates acidic treatment of cell harvest, demonstrating high process yield, improved clearance of host cell associated contaminants, like non-histone host cell protein, histone, DNA and heteroaggregates. Host protein contamination was reduced about 10-fold compared to protein A loaded with harvest clarified by centrifugation and microfiltration. Turbidity increase of eluted IgG upon pH neutralization was nearly eliminated. Residual levels of impurities in the protein A eluate were achieved that potentially meet requirements of drug substance and thus alleviate the burden for further impurities removal in subsequent chromatography steps. The mechanism of host cell associated contaminants removal during acidic treatment was also explored. After a polishing step by Capto adhere, host cell protein was reduced to less than 5 ppm, DNA less than 1 ppb, histone to undetectable level, heteroaggregates less than 0.01% with total IgG recovery around 87%. This efficient process can be easily integrated into current IgG purification platforms, and may overcome downstream processing challenges.
治疗性单克隆抗体已成为生物制药市场中的主要产品类别。作为首个捕获步骤的蛋白A在当前单克隆抗体纯化平台中仍占据主导地位。在本研究中，我们开发了一种新的抗体收获工艺，该工艺结合了对细胞收获物的酸性处理，显示出高工艺产率，提高了对宿主细胞相关污染物（如非组蛋白宿主细胞蛋白、组蛋白、DNA和杂聚体）的清除率。与采用离心和微滤澄清收获物上样的蛋白A相比，宿主蛋白污染降低了约10倍。pH中和后洗脱的IgG的浊度增加几乎消除。实现了蛋白A洗脱液中杂质的残留水平，这有可能满足原料药的要求，从而减轻后续色谱步骤中进一步去除杂质的负担。还探讨了酸性处理过程中去除宿主细胞相关污染物的机制。经过Capto adhere抛光步骤后，宿主细胞蛋白降至5 ppm以下，DNA降至1 ppb以下，组蛋白降至检测不到的水平，杂聚体低于0.01%，总IgG回收率约为87%。这种高效的工艺可以很容易地整合到当前的IgG纯化平台中，并可能克服下游加工挑战。
