Transient gene expression (TGE) technology enables the rapid production of large amount of recombinant proteins, without the need of fastidious screening of the producing cells required for stable transfection (ST). However, several barriers must be overcome before reaching the production yields using ST. For optimizing the production yields from suspended cells using TGE, a better understanding of the transfection conditions at the single cell level are required. In this study, a universal droplet microfluidic platform was used to assess the heterogeneities of CHO-S population transiently transfected with cationic liposomes (CL) (lipoplexes) complexed with GFP-coding plasmid DNA (pDNA). A single cell analysis of GFP production kinetics revealed the presence of a subpopulation producing higher levels of GFP compared with the main population. The size of high producing (HP) cells, their relative abundance, and their specific productivity were dependent on the charge and the pDNA content of the different lipoplexes: HPs showed increased cell size in comparison to the average population, lipoplexes with positive charge produced more HPs, and lipoplexes carrying a larger amount of pDNA yielded a higher specific productivity of HPs. This study demonstrates the potential for time-resolved single-cell measurements to explain population dynamics from a microscopic point of view.

中文翻译：

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跟踪微流控平台中瞬时转染的单个细胞的演变。

瞬时基因表达 (TGE) 技术能够快速生产大量重组蛋白，而无需对稳定转染 (ST) 所需的生产细胞进行严格筛选。然而，在使用 ST 达到生产良率之前，必须克服几个障碍。为了使用 TGE 优化悬浮细胞的产量，需要更好地了解单细胞水平的转染条件。在这项研究中，通用液滴微流控平台用于评估瞬时转染与 GFP 编码质粒 DNA (pDNA) 复合的阳离子脂质体 (CL) (lipoplexes) 的 CHO-S 群体的异质性。对 GFP 生产动力学的单细胞分析显示，与主要人群相比，存在产生更高水平 GFP 的亚群。高产 (HP) 细胞的大小、它们的相对丰度和它们的比生产率取决于电荷和不同 lipoplexes 的 pDNA 含量：与平均细胞群相比，HPs 的细胞大小增加，带正电荷的 lipoplexes 产生更多HPs 和携带大量 pDNA 的脂质复合物产生了更高的 HPs 比生产率。这项研究证明了时间分辨单细胞测量从微观角度解释种群动态的潜力。携带大量pDNA的脂质复合物产生了更高的HP比生产率。这项研究证明了时间分辨单细胞测量从微观角度解释种群动态的潜力。携带大量pDNA的脂质复合物产生了更高的HP比生产率。这项研究证明了时间分辨单细胞测量从微观角度解释种群动态的潜力。