Development of a novel inducible expression system for the manufacture of therapeutic proteins from CHO cells.

生产对宿主细胞系生长有毒性或有害影响的生物制药是非常具有挑战性的。为了克服这一挑战，研究人员开发了许多启动子，允许在生物生产过程中控制蛋白质的表达。这项研究的主要目的是开发一个两步生物处理平台，在获得足够的生物量或对DSP或产品质量有负面影响的基因可以被沉默后，目标基因的表达被开启。这种类型的过程特别适合于生产难以表达或有毒的蛋白质，在这些蛋白质中，表达对细胞有害，或者宿主细胞蛋白与最终产品共同纯化，并使纯化策略复杂化。然而，到目前为止，这些启动子已经被证明对观察到的表达泄漏的任务没有足够的控制，或者需要多轮转染和细胞系选择来实现必要的控制。理想情况下，这些启动子的活性应该可以在生产过程中被胁迫刺激(化学或物理)诱导/抑制，并允许对表达水平进行严格控制，以确保最终产品的最大生产率和高质量。为此，Synproics使用其专利技术开发了新的人工诱导/可抑制系统，这些系统已经展示了对基因表达的精细控制。与目前可用的系统相比，这些系统具有显著的优势，因为它们体积小，可以由一个质粒驱动，提供基因表达的微调，由无毒的生理或化学刺激驱动，因此是在CHO细胞生物生产期间提高生产率和最大限度降低成本的理想选择。使用这些新的基因表达控制工具，Synproics和Lonza将开始为期18个月的示范计划，以验证这些控制工具在GMP环境中的使用，使用具有良好特性的模型蛋白质。一旦在工业相关的情况下得到验证，这些工具将被用于设计治疗构造的工艺，并将开发制造工艺。除了这一结果，Synproics的控制工具的验证将增加生物生产的灵活性，并为该行业提供新的强大工具，用于增加可以从CHO细胞生产的蛋白质的数量和类型。

Production of biopharmaceuticals that are toxic or have detrimental effects on the growth of the host cell line is very challenging. To overcome this challenge researchers have developed a number of promoters allowing control of protein expression during the bioproduction process. The primary aim of that research was to enable a 2-step bioprocessing platform to be developed whereby the expression of the gene of interest is switched on after sufficient biomass has been obtained or a gene that has negative effects on DSP or product quality can be silenced. This type of process is particularly attractive for the production of difficult to express or toxic proteins where expression is deleterious to the cell or where host cell protens co-purify with the final product and complicate purification strategies. However, to date these promoters have proven to have insufficient control for the task with leaky expression observed or the need for multiple rounds of transfection and cell line selection to achieve the requisite control. Ideally the activity of those promoters should be inducible/repressible by a stress stimulus (chemical or physical) during the production process and allow tight control over the expression levels to ensure maximum productivity and high quality of the final product. To this end Synpromics has used its proprietary technology to develop new synthetic inducible/repressible systems that have demonstrated exquisite control of gene expression. These systems offer significant advantages over the currently available systems as they are small in size, can be driven from one plasmid, offer fine tuning of gene expression, are driven by physiological or chemical stimulus that are non-toxic and are therefore ideal for improving productivity and minimising costs during bioproduction in CHO cells. Using these novel gene expression control tools Synpromics and Lonza will embark on an 18 month exemplification program to validate the use of these control tools in a GMP environment using well characterized model proteins. Once validated in an industrially relevant situation, these tools will then be used to design a process for a therapeutic construct and a manufacturing process will be developed. In addition to this outcome, the validation of Synpromics's control tools will increase the flexibility of bioproduction and offer the industry new powerful tools with which to increase the number and type of proteins that can be produced from CHO cells.