共查询到16条相似文献,搜索用时 78 毫秒
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以悬浮适应的表达尿激酶原CHO工程细胞为研究对象,在100mL的摇瓶中进行无血清悬浮培养,以细胞密度、细胞活力、Pro-UK活性、葡萄糖比消耗速率(qglc)、乳酸比生产速率(qlac)、乳酸对葡萄糖的得率系数(Ylac/glc)为观察指标,同时以细胞有血清悬浮培养作为参照,考察CHO工程细胞无血清悬浮培养生长和代谢特征。观察结果表明,CHO工程细胞在无血清及有血清悬浮培养条件下表现为大致相似的细胞生长和代谢特征。在此基础上,依据实际检测的数据,应用MATLAB软件对细胞对数生长期的细胞生长、乳酸生成及葡萄糖消耗的模型参数进行非线性规划,获得全局性收敛的最优参数估计值,建立了细胞在无血清培养条件下的生长及代谢动力学模型。 相似文献
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CHO工程细胞 (11G-S) 悬浮培养的无血清培养基的设计 总被引:1,自引:1,他引:1
以悬浮适应的表达重组尿激酶原 (Pro-urokinase,pro-UK) CHO工程细胞系11G-S为对象,采用Plackett-Burman实验设计及响应面分析法,设计支持CHO工程细胞 (11G-S) 悬浮生长的无血清培养基。以细胞密度为评价指标,在单因素实验的基础上采用Plackett-Burman实验设计对影响细胞生长的培养基添加成分进行考察,确定了3种对细胞生长明显促进作用的培养基添加成分:胰岛素、转铁蛋白及腐胺。继而利用响应面法分析了这3种添加成分的最佳水平范围,设计了一种适用于CHO工程细胞 (11G-S) 悬浮培养的无血清培养基SFM-CHO-S。11G-S细胞在SFM-CHO-S批次悬浮培养的细胞最大生长密度达到4.12×106 cells/mL,pro-UK的最大累积活性达到5 614 IU/mL,培养效果优于商品化的同类无血清培养基。 相似文献
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产HBsAg CHO细胞无血清培养研究 总被引:2,自引:0,他引:2
在分析CHO C2 8细胞对培养基中氨基酸利用的基础上 ,对DMEM培养基进行初步优化。再采用统计学正交分析方法 ,在初步优化的DMEM培养基中添加胰岛素、转铁蛋白等促细胞生长因子 ,建立了一种适于CHO C2 8细胞持续用无血清培养基———CHO C2 8 SFM。经转瓶维持实验 ,在CHO C2 8 SFM中维持培养的细胞 ,其乙型肝炎表面抗原 (HBsAg)表达水平达到用含 5 %FBS培养液维持的 70 %~ 80 % ,但纯化收率提高 1 0 %以上 ,可用于大规模生产。 相似文献
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在动物细胞培养过程中对培养体系实施培基连续灌流能及时地补充细胞生长所需的营养物质、控制细胞代谢产物对细胞的影响,实现细胞的高密度长期培养,提高目的产品的生产效率[1,2].细胞连续灌流培养的前提是在实施培基连续灌流的同时培养体系能有效地截留细胞[3]. 相似文献
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以 Cytopore 多孔微球固定产重组组织型纤溶酶原激活剂(rt P A) C H O 工程细胞株4 B3 ,在2 L 搅拌式生物反应器用无血清培养基 D F5 S 连续灌流培养。4 B3 细胞的最大活细胞密度和rt P A 生产水平分别达到883 ×106/ m L 和12473 I U/ m L。含rt P A 的4 B3 细胞培养上清经 M P G 吸附层析和 Lysinesepharose 4 B 亲和层析两步纯化,rt P A 的纯度达到98 % 。 相似文献
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在动物细胞培养过程中对培养体系实施培基连续灌流能及时地补充细胞生长所需的营养物质、控制细胞代谢产物对细胞的影响 ,实现细胞的高密度长期培养 ,提高目的产品的生产效率[1,2 ] 。细胞连续灌流培养的前提是在实施培基连续灌流的同时培养体系能有效地截留细胞[3] 。这一前提增加了细胞培养装置的复杂程度 ,使之特化为价格昂贵的生物反应器 ,限制了细胞连续灌流培养的应用。如能通过对普通的细胞搅拌培养瓶进行改进 ,使之能用于细胞的连续灌流培养 ,则有利于细胞连续灌流培养的推广应用。1 材料和方法1 1 细胞产人重组凝血酶原CHO工… 相似文献
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研究以DMEM/F12(1:1 V/V)培养基为基础,添加不同添加剂优化一种适宜CHO DG44细胞生长的廉价培养基。以细胞密度和细胞活率为主要指标,对DMEM/F12(1:1 V/V)培养基进行了优化。通过正交试验和单因素试验筛选出了CHO DG44细胞生长的最佳培养基。正交试验结果表明添加8mg/L Insulin、10mg/L Transferrin、12mM Glutamine、9mg/L Ethanolamine、9mg/L Sodium selenite、0.5×Lipids、0.5×Vitamin,对细胞生长有较好促进作用,细胞密度从0.6×106 cells/mL上升到1.8×106 cells/mL。在此基础上添加2.5g/L Malt Peptone和2.5g/L YeastExtract可使细胞密度达到2.65×106 cells/mL,基本上达到商业培养基的培养效果,而成本降低了约60%。 相似文献
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Insulin-like growth factor I has similar mitogenic effects to insulin, a growth factor required by most cells in culture,
and it can replace insulin in serum-free formulations for some cells. Chinese Hamster Ovary cells grow well in serum-free
medium with insulin and transferrin as the only exogenous growth factors. An alternative approach to addition of exogenous
growth factors to serum-free medium is transfection of host cells with growth factor-encoding genes, permitting autocrine
growth. Taking this approach, we constructed an IGF-I heterologous gene driven by the cytomegalovirus promoter, introduced
it into Chinese Hamster Ovary cells and examined the growth characteristics of Insulin-like growth factor I-expressing clonal
cells in the absence of the exogenous factor. The transfected cells secreted up to 500 ng/106 cells/day of mature Insulin-like growth factor I into the conditioned medium and as a result they grew autonomously in serum-free
medium containing transferrin as the only added growth factor. This growth-stimulating effect, observed under both small and
large scale culture conditions, was maximal since no further improvement was observed in the presence of exogenous insulin.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Serum-free large-scale transient transfection of CHO cells 总被引:11,自引:0,他引:11
Derouazi M Girard P Van Tilborgh F Iglesias K Muller N Bertschinger M Wurm FM 《Biotechnology and bioengineering》2004,87(4):537-545
To date, methods for large-scale transient gene expression (TGE) in cultivated mammalian cells have focused on two transfection vehicles: polyethylenimine (PEI) and calcium phosphate (CaPi). Both have been shown to result in high transfection efficiencies at scales beyond 10 L. Unfortunately, both approaches yield higher levels of recombinant protein (r-protein) in the presence of serum than in its absence. Since serum is a major cost factor and an obstacle to protein purification, our goal was to develop a large-scale TGE process for Chinese hamster ovary (CHO) cells in the absence of serum. CHO-DG44 cells were cultivated and transfected in a chemically defined medium using linear 25 kDa PEI as a transfection vehicle. Parameters that were optimized included the DNA amount, the DNA-to-PEI ratio, the timing and solution conditions for complex formation, the transfection medium, and the cell density at the time of transfection. The highest levels of r-protein expression were observed when cultures at a density of 2.0 x 10(6) cells/ml were transfected with 2.5 microg/ml DNA in RPMI 1640 medium containing 25 mM HEPES at pH 7.1. The transfection complex was formed at a DNA:PEI ratio of 1:2 (w/w) in 150 mM NaCl with a 10-min incubation at room temperature prior to addition to the culture. The procedure was scaled up for a 20-L bioreactor, yielding expression levels of 10 相似文献
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Summary A monolayer culture system has recently been developed for the extended growth and serial passage of normal rat mammary epithelial
(RME) cells. In this system the cells undergo greater than 20 population doublings when grown on type I collagen-coated tissue
culture dishes in Ham's F12 medium supplemented with insulin, hydrocortisone, epidermal growth factor, prolactin, progesterone,
cholera toxin, and 5% fetal bovine serum (FBS). The purpose of the present studies was to define additional growth factors
that would allow equivalent RME cell proliferation in serum-free medium. Ethanolamine (EA) was effective at reducing the FBS
requirements for RME cell proliferation and at its optimum concentration did so by greater than 20-fold. Even with optimum
levels of EA there was essentially no cell proliferation in the absence of FBS. However, addition of bovine serum albumin
(BSA) to the hormone, growth factor, and EA-supplemented medium resulted in substantial proliferation in the absence of serum,
and the further addition of transferrin (T) potentiated this effect. Thus, in this culture system, replacement of FBS with
EA, BSA, and T resulted in RME cell proliferation in primary culture which was equivalent to that obtained in the 5% FBS-containing
medium.
This work was supported by grant RR-05529 from the Division of Research Resources, National Institutes of Health, Bethesda,
MD, and by Public Health Service grant CA40064-01 from the National Cancer Institute, Bethesda, MD. 相似文献