治疗性抗体如单克隆抗体、双特异性抗体、以及抗体片段几乎占据了治疗性生物制品的半壁江山,各大药企的竞争十分激烈,其中下游纯化工艺是药物开发的关键环节。主流的抗体纯化通常包含三步层析、两步过滤、以及病毒灭活和浓缩换液等,Protein A因与IgG的Fc片段具有高特异性而广泛应用于抗体的纯化阶段。Protein A亲和层析是抗体纯化捕获阶段的“金方法”,对于整个抗体的纯化来说具有重要意义。实际上,市面上已有多种Protein A被用于药物生产工艺中,常见的Protein A亲和配基有天然Protein A、重组Protein A及耐碱性Protein A,如MabSelect SuReTM、PrismA等。
当使用Protein A亲和层析进行抗体纯化时,Protein A有一定概率与抗体同时从填料上脱落,这种现象称为“Protein A Leaching”,尤其是当色谱柱循环使用老化时,Protein A更容易脱落导致抗体污染,这可能对抗体药物的安全性和有效性造成严重影响。因而,对使用Protein A亲和层析填料纯化的抗体制剂中残留Protein A的检测,是抗体药物制剂生产过程中关键的质量控制步骤之一,国内外药品监管机构也发布了相关的技术要求文件,对抗体药物Protein A的残留量做出明确的规定,为抗体药物的研发和生产提供了参考。值得注意的是,面对市面上多种多样的商业化Protein A亲和填料类型,选择一款通用性强、回收率高的Protein A残留检测工具是药物工艺质控环节需要考量的关键要素。
实际上,多数Protein A残留检测试剂盒会遇到Protein A分析回收率低的问题,通常是因为1)样品是不完整的抗体片段,2)以偶联蛋白形式存在如抗体分子与另一个非抗体分子相连。当面对这些非典型的抗体药结构状态时,传统的样品预处理流程如解离、变性、沉淀去除原料药等步骤可能无法充分解离或变性这些特殊结构的蛋白质,导致处理后的样品中仍残留有未完全变性的药物成分,存在与浸出的Protein A重新结合的可能,进而干扰ELISA检测结果,造成回收率显著下降。因此,针对Protein A残留检测,需重点优化或开发新的样品预处理技术,来确保目标蛋白成分如抗体药都能被有效解离、变性和去除,以提高ELISA回收率,进而提升检测准确性。
【免煮型 高回收率】
Protein A Quick ELISA Kit(Boiling-free)
为解决上述难点,ACROBiosystems百普赛斯通过优化样本中抗体药物与Protein A的解离工艺,成功研发出基于双抗体夹心酶联免疫法(夹心法ELISA)的免煮型高回收率resDetect™ 快速通用型Protein A ELISA检测试剂盒(货号:RES-A029),可用于判断抗体、Fc融合蛋白等药物制剂的中间产物或者终产品中存在的天然或重组Protein A,以及常用的各种耐碱性重组Protein A如MabSelect SuRe™、PrismA、MaXtar® ARPA ligand Protein A的脱落残留,具有样品处理简单、回收率高等优势,满足药企残留定量分析检测、优化相关药物纯化工艺的需求,加速生物药上市进程!
• 高回收率:通过优化样本解离过程,提升回收合格率。经多样本验证Protein A回收合格率高且稳定;
• 通用性:适用于检测天然或结构保守的重组Protein A和各种常见的耐碱性Protein A突变体,如MabSelect SuRe™和PrismA亲和配基;
• 样本前处理简便:无需煮沸和离心样本,节省样本处理时间;
• 准确性:Protein A标准品按照药典方法进行严格定量和溯源,具有可追溯性;
• 严格的方法学验证:可根据要求提供符合ICH标准的验证报告;
• 高浓度IgG耐受性:准确定量高达20 mg/mL抗体中的Protein A水平。
• 高普适性,多种形式Protein A或变体适用
提供4种不同类型的标准品,适用于目前商业化的大部分Protein A及变体亲和层析填料的残留检测。
The minimum detectable concentration of different forms of protein A are 40 pg/mL. The minimum detectable concentration was determined by adding twice standard deviations to the mean optical density value of twenty zero standard replicates and calculating the corresponding concentration.
• 高回收率
针对非天然结构的抗体药物经常会遇到的Protein A检测回收率低的问题,ACROBiosystems百普赛斯通过优化样本中抗体药物与Protein A的解离工艺,成功解决这类样本的低回收率问题。
Total 53 samples were tested by ACRO and Competitor C kits simultaneously. 45 samples tested by ACRO (Cat. NO. RES-A029) kit fell into the acceptable recovery range (80-120%), and only 11 samples tested by competitor C kit fell into the acceptable recovery range.
• 极低非特异
具备良好的Protein A检测特异性,与竞品相比无非特异性检出。
3 monoclonal antibody samples which not contain Protein A were tested by ACRO and Competitor P kits simultaneously. All 3 testing results tested by ACRO kit were below LOD (blank+2SD, red line), meanwhile, all 3 testing results tested by Competitor P kit were far beyond the LOD (blank+2SD, green line). Those data show there are non-specific binding of Competitor P kit.
• 高浓度IgG耐受性
对不同类型的抗体药物具有良好的耐受性,最高耐受浓度可以达到20mg/mL。
For Bevacizumab and Toripalimab, at low spiked concentration of Protein A (0.01ppm) level, ACRO is better than Competitor C; meanwhile at high spiked concentration of Protein A (0.05ppm) level, the recovery rate of both are acceptable. For IVIG, the recovery rate for competitor C is not acceptable at both low and high spiked concentration of Protein A. But the recovery rate performance of ACRO are good at both levels. The results indicated that ACRO (Cat. NO. RES-A029) was well tolerated when detecting Protein A residue in 20mg/mL IVIG.
For Bevacizumab,the recovery rate for both kits are acceptable at low and high spiked Protein A level. For Toripalimab, at low spiked concentration of Protein A (0.01ppm) level, ACRO is better than Competitor P; meanwhile at high spiked concentration of Protein A (0.05ppm) level, the recovery rate of both are acceptable. For IVIG, the recovery rate for competitor P is not acceptable at both low and high spiked concentration of Protein A. But the recovery rate performance of ACRO are good at both levels. The results indicated that ACRO (Cat. NO. RES-A029) was well tolerated when detecting Protein A residue in 20mg/mL IVIG.
• 兼容多种不同的缓冲液体系
抗体纯化中常用的缓冲液体系对Protein A检测结果无干扰。
ACROBiosystems百普赛斯生物科技股份有限公司
北京:010-53681107
上海:021-50850665
邮箱:(产品订购)order.cn@acrobiosystems.com
邮箱:(技术支持)tech.cn@acrobiosystems.com
邮箱:(廉洁合规)lianjie@acrobiosystems.com
地址:北京经济技术开发区宏达北路8号5号楼4层