Impact of CPP's on primary human NK cell CQAs during cell expansion – an experimental study using design of experiments

Abstract: Human natural killer (NK) cells represent a promising leukocyte population for use in immune cell therapies. Hematologic as well as solid tumors have been shown to respond to treatment with autologous or allogeneic NK cells. Providing NK cells in sufficient quantity and quality (i.e. efficacy, safety, identity, purity, and yield), remains a challenge. A deeper insight into the critical process parameters (CPP) and critical quality attributes (CQA) of primary NK cell culture is needed for the understanding and control of NK cell manufacturing. Due to the large number of potential CPP’s, a design of experiments (DoE) approach was used for systematic planning and reduction of the number of experiments. Primary NK cells from two donors were cultivated under batch conditions and varying CPP’s. A detailed analysis of the impact of the investigated CPP’s was conducted and the DoE based experimental setup allowed the interpretation of the influence of each selected process parameter as well as their combination on the relevant CQAs. Based on this data, a statistical model was formulated, which allows predictions of the maximal viable cell number. This approach allows for detailed insight into the CPP’s and possible optimizations in the production of cell therapy products.摘要： 人类自然杀伤细胞（natural killer cells, NK）是一类极具应用前景的免疫细胞治疗用白细胞群。已有研究证实，血液系统肿瘤与实体瘤均可通过自体或异体NK细胞疗法产生治疗应答。然而，获取数量充足且质量达标（即有效性、安全性、细胞同一性、纯度及产出率）的NK细胞仍是一项挑战。为实现NK细胞生产过程的理解与精准调控，亟需深入解析原代NK细胞培养的关键工艺参数（critical process parameters, CPP）与关键质量属性（critical quality attributes, CQA）。鉴于潜在关键工艺参数数量众多，本研究采用实验设计（design of experiments, DoE）方法开展系统化规划并缩减实验规模。本研究选取两名供者来源的原代NK细胞为实验材料，在分批培养条件下改变关键工艺参数进行培养。随后对所考察的关键工艺参数的影响进行了详细分析，基于实验设计的实验设置可解析各选定工艺参数及其组合对相关关键质量属性的影响。基于上述实验数据，本研究构建了可预测最大活细胞数的统计模型。该方法可深入解析关键工艺参数，并为细胞治疗产品的生产优化提供可行路径。