在连续高细胞密度培养中产生逆转录病毒载体
Marc D Hein1, Daniel Kazenmaier2,3, Yasemin van Heuvel4,5
1Chair of Bioprocess Engineering, Otto-Von-Guericke-University Magdeburg, Magdeburg, Germany.
Applied microbiology and biotechnology
|August 5, 2023
概括
这项研究开发了一种持续的高细胞密度过程,用于产生小鼠白血病病毒 (MLV) 载体,实现高可活细胞度和载体标位. 该过程显著增加了空间时间的产量,以有效地生产病毒载体.
科学领域:
- 生物技术是生物技术.
- 基因治疗 基因治疗
- 细胞培养工程 细胞培养工程
背景情况:
- 鼠类白血病病毒 (MLV) 载体对于体基因疗法至关重要,特别是用于修改造血细胞干细胞.
- 之前的工作建立了一个悬浮病毒包装细胞系 (VPC) 使用转基因人类胚胎293-F (HEK293-F) 细胞用于MLV载体的生产.
- 需要有效和可扩展的生产方法来满足对MLV载体日益增长的需求.
研究的目的:
- 建立一个连续的高细胞密度 (HCD) 过程,使用专门的HEK293-F细胞系产生MLV载体.
- 优化细胞培养条件并实施强化策略,以最大限度地提高载体产量.
- 评估病毒载体的连续采集方法的效率.
主要方法:
- 选各种介质以确定小规模的最大可活细胞度 (VCC).
- 扩展到混合生物反应器,然后使用交替触流 (ATF) 过实现 perfusion culture.
- 开发了一种连续的HCD工艺,利用管状膜进行细胞保留和同时收集载体.
主要成果:
- 在 perfusion 培养中,高达 27.4 x 10^6 细胞/mL 的高VCC 和高达 8.6 x 10^6 传感单位/mL 的 MLV 载体标位.
- 使用管状膜的连续HCD工艺,与批量种植相比,产生了18倍更高的时空产量.
- 连续收集病毒载体的可行性与HCD培养相结合.
结论:
- 持续高细胞密度培养是一种可行的策略,用于高产量的MLV载体的生产.
- 整合连续向量采集与HCD过程显著提高了生产效率.
- 开发的过程提供了一个可扩展和高效的平台,用于制造基因治疗应用的病毒载体.
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