背景:因子设计是一个简单的,然而优雅的方法来研究多个因素及其相互作用对特定反应的影响。因此,这种类型的研究设计达到了工艺的最佳优化条件。尽管变量之间的相互作用在细胞培养程序中广泛普遍存在,析因设计本身很少用于提高细胞培养输出。因此,我们旨在优化产生成熟骨髓来源的树突状细胞(BMDCs)的实验条件.研究了两个不同的变量,包括诱导因子的浓度和骨髓单个核细胞的起始密度。在目前的研究中,我们利用实验设计(DoE),统计方法,系统评估不同水平的因素对细胞培养结果的影响。在这里,我们应用两个因素,两水平(22)阶乘实验,导致四个条件一式三份运行。这里研究的两个变量是具有两个水平的细胞因子组合,单独或与白细胞介素-4(IL4)一起使用粒细胞-巨噬细胞集落刺激因子(GM-CSF)。另一个参数是两种不同浓度的细胞密度,2×106和4×106细胞/mL。然后,我们使用锥虫蓝排除法测量细胞活力,使用流式细胞仪检测表达标志物FITC-CD80、CD86、CD83和CD14的BMDCs。使用平均荧光强度(MFI)的任意单位(AU)计算BMDC标志物表达水平。
结果:目前的研究表明,以2×106细胞/mL接种并用GM-CSF和IL-4处理的细胞组中获得的总存活细胞和细胞产量最高。重要的是,共刺激分子CD83和CD80/CD86的表达对2×106细胞/mL的细胞密度有统计学意义(P<0.01,双向ANOVA)。在细胞因子混合物存在下以4×106接种的骨髓单核细胞不太有效地分化并成熟为BMDC。通过双向ANOVA的统计学分析揭示了细胞密度和细胞因子组合之间的相互作用。
结论:本研究的分析表明细胞因子组合和细胞密度之间对BMDC成熟的实质性相互作用。然而,较高的细胞密度与优化DC成熟无关。值得注意的是,在生物工艺设计中应用DoE提高了实验效率和可靠性,同时最大限度地减少了实验,时间,和工艺成本。
BACKGROUND: Factorial design is a simple, yet elegant method to investigate the effect of multiple factors and their interaction on a specific response simultaneously. Hence, this type of
study design reaches the best optimization conditions of a process. Although the interaction between the variables is widely prevalent in cell culture procedures, factorial design per se is infrequently utilized in improving cell culture output. Therefore, we aim to optimize the experimental conditions for generating mature bone marrow-derived dendritic cells (BMDCs). Two different variables were investigated, including the concentrations of the inducing factors and the starting density of the bone marrow mononuclear cells. In the current
study, we utilized the design of experiments (
DoE), a statistical approach, to systematically assess the impact of factors with varying levels on cell culture outcomes. Herein, we apply a two-factor, two-level (22) factorial experiment resulting in four conditions that are run in triplicate. The two variables investigated here are cytokines combinations with two levels, granulocyte-macrophage colony-stimulating factor (GM-CSF) alone or with interleukin-4 (IL4). The other parameter is cell density with two different concentrations, 2 × 106 and 4 × 106 cells/mL. Then, we measured cell viability using the trypan blue exclusion method, and a flow cytometer was used to detect the BMDCs expressing the markers FITC-CD80, CD86, CD83, and CD14. BMDC marker expression levels were calculated using arbitrary units (AU) of the mean fluorescence intensity (MFI).
RESULTS: The current
study showed that the highest total viable cells and cells yield obtained were in cell group seeded at 2 × 106 cells/mL and treated with GM-CSF and IL-4. Importantly, the expression of the co-stimulatory molecules CD83 and CD80/CD86 were statistically significant for cell density of 2 × 106 cells/mL (P < 0.01, two-way ANOVA). Bone marrow mononuclear cells seeded at 4 × 106 in the presence of the cytokine mix less efficiently differentiated and matured into BMDCs. Statistical analysis via two-way ANOVA revealed an interaction between cell density and cytokine combinations.
CONCLUSIONS: The analysis of this
study indicates a substantial interaction between cytokines combinations and cell densities on BMDC maturation. However, higher cell density is not associated with optimizing DC maturation. Notably, applying
DoE in bioprocess designs increases experimental efficacy and reliability while minimizing experiments, time, and process costs.