Chrobok Michael, Dahlberg Carin I M, Sayitoglu Ece Canan, Beljanski Vladimir, Nahi Hareth, Gilljam Mari, Stellan Birgitta, Sutlu Tolga, Duru Adil Doganay, Alici Evren
Center for Hematology and Regenerative Medicine, Department of Medicine Huddinge, Karolinska Institutet, 141 83 Stockholm, Sweden.
NSU Cell Therapy Institute, Nova Southeastern University, Fort Lauderdale, FL 33314, USA.
Cancers (Basel). 2019 Jan 10;11(1):69. doi: 10.3390/cancers11010069.
Natural killer (NK) cells stand out as promising candidates for cellular immunotherapy due to their capacity to kill malignant cells. However, the therapeutic use of NK cells is often dependent on cell expansion and activation with considerable amounts of serum and exogenous cytokines. We aimed to develop an expansion protocol for NK-92 cells in an effort to generate a cost-efficient, xeno-free, clinical grade manufactured master cell line for therapeutic applications. By making functional assays with NK-92 cells cultured under serum-free conditions (NK-92) and comparing to serum-supplemented NK-92 cells (NK-92) we did not observe significant alterations in the viability, proliferation, receptor expression levels, or in perforin and granzyme levels. Interestingly, even though NK-92 cells displayed decreased degranulation and cytotoxicity against tumor cells in vitro, the degranulation capacity was recovered after overnight incubation with 20% serum in the medium. Moreover, lentiviral vector-based genetic modification efficiency of NK-92 cells was comparable with NK-92 cells. The application of similar strategies can be useful in reducing the costs of manufacturing cells for clinical use and can help us understand and implement strategies towards chemically defined expansion and genetic modification protocols.
自然杀伤（NK）细胞因其具有杀伤恶性细胞的能力，成为细胞免疫治疗中颇具潜力的候选者。然而，NK细胞的治疗应用通常依赖于用大量血清和外源性细胞因子进行细胞扩增和激活。我们旨在开发一种NK-92细胞的扩增方案，以努力生成一种具有成本效益、无动物源成分、临床级别的主细胞系用于治疗应用。通过对在无血清条件下培养的NK-92细胞（NK-92）进行功能测定，并与补充血清的NK-92细胞（NK-92）进行比较，我们未观察到细胞活力、增殖、受体表达水平或穿孔素和颗粒酶水平有显著变化。有趣的是，尽管NK-92细胞在体外对肿瘤细胞的脱颗粒和细胞毒性有所降低，但在培养基中加入20%血清过夜孵育后，脱颗粒能力得以恢复。此外，基于慢病毒载体的NK-92细胞基因修饰效率与NK-92细胞相当。应用类似策略有助于降低临床用细胞的生产成本，并能帮助我们理解和实施针对化学限定的扩增和基因修饰方案的策略。
