Cell Biology Unit, Faculty of Natural Sciences and Engineering, Åbo Akademi University, Turku, Finland.
Cell Biology Unit, Faculty of Natural Sciences and Engineering, Åbo Akademi University, Turku, Finland
Anticancer Res. 2021 Jul;41(7):3281-3285. doi: 10.21873/anticanres.15114.
BACKGROUND/AIM: Recent studies have indicated that natural killer (NK) cells present in peripheral blood mononuclear cells (PBMCs) might be responsible for the somewhat poor outcome of clinical trials conducted with the NK cell line NK-92, as well as chimeric antigen receptor-modified NK-92 cells against leukemias and lymphomas. These NK cells and how their cytotoxic profiles can be altered by some common gamma chain receptor-dependent cytokines or by removal of CD4 cells have been addressed herein.
A time-resolved fluorometric assay using 2.2':6'.2"-terpyridine-6.6"-dicarboxylic acid-labeled NK-92 or K562 as target cells was used for measuring the cytotoxic activity of cytokine-treated PBMCs and purified NK cells.
Pre-incubation with 25 ng/ml interleukin 12 (IL-12), IL-15 or IL-21 for 72 h increased NK cell activity against K562 cells by more than 90% (1:25 target:effector ratio), whereas the corresponding NK cell activity against NK-92 cells was reduced by 15.9±0.1% by IL-12 and 50.6±2.9% by IL-15 compared to cells treated with medium alone. IL-7, on the other hand, increased NK activity against K562 to a much smaller extent (10.4±0.4%) and inhibited NK-92 cell lysis by 15.2±0.3%. Interestingly, similar amounts of IL-2 potentiated NK cell activity against both K562 and NK-92 cells by 50.9±0.5% and 14.3±0.9%, respectively. Purification of NK cells with magnetic beads demonstrated that NK cells indeed were responsible for the observed cytotoxic activity against both NK-92 cells (58.5±9.10%, 1:100 target:effector ratio) and K562 cells (81.6±9.57%, 1:100 target:effector ratio). Elimination of CD4+ cells from PBMCs did not alter the NK activity profile.
This study highlights a problem that might arise with immune-based NK-92 and chimeric antigen receptor-transduced NK-92 cell therapies and pinpoints the need for evaluating new NK-like cell lines.
背景/目的：最近的研究表明，外周血单个核细胞（PBMCs）中存在的自然杀伤（NK）细胞可能是导致 NK 细胞系 NK-92 以及嵌合抗原受体修饰的 NK-92 细胞在白血病和淋巴瘤临床试验中结果不佳的原因。本文研究了这些 NK 细胞及其细胞毒性谱如何被一些常见的γ链受体依赖性细胞因子改变，或通过去除 CD4 细胞来改变。
使用 2.2':6'.2"-三联吡啶-6.6"-二羧酸标记的 NK-92 或 K562 作为靶细胞的时间分辨荧光测定法，用于测量细胞因子处理的 PBMC 和纯化的 NK 细胞的细胞毒性活性。
用 25 ng/ml 白细胞介素 12（IL-12）、IL-15 或 IL-21 预孵育 72 小时，可使 NK 细胞对 K562 细胞的活性增加超过 90%（1:25 靶标：效应物比），而相应的 NK 细胞对 NK-92 细胞的活性则降低 15.9±0.1%（IL-12）和 50.6±2.9%（IL-15）。相比之下，单独用培养基处理的细胞。另一方面，白细胞介素 7 仅使 K562 的 NK 活性增加很小的程度（10.4±0.4%），并抑制 NK-92 细胞的裂解 15.2±0.3%。有趣的是，相同量的白细胞介素 2 分别通过 50.9±0.5%和 14.3±0.9%增强了对 K562 和 NK-92 细胞的 NK 细胞活性。用磁珠纯化 NK 细胞表明，NK 细胞确实对观察到的 NK-92 细胞（58.5±9.10%，1:100 靶标：效应物比）和 K562 细胞（81.6±9.57%，1:100 靶标：效应物比）的细胞毒性活性负责。从 PBMC 中去除 CD4+细胞不会改变 NK 活性谱。
本研究强调了可能在基于免疫的 NK-92 和嵌合抗原受体转导的 NK-92 细胞治疗中出现的问题，并指出需要评估新的 NK 样细胞系。
