Objective To evaluate the cytotoxicity of six commonly used copper-bearing intrauterine devices (Cu-IUDs) on Chinese hamster ovary (CHO-K1) cells and to investigate the influence of frame, shape and copper surface...Objective To evaluate the cytotoxicity of six commonly used copper-bearing intrauterine devices (Cu-IUDs) on Chinese hamster ovary (CHO-K1) cells and to investigate the influence of frame, shape and copper surface area of Cu-IUDs on cell toxicity.Methods Cu-IUDs were incubated in 10% FBS-DMEM/F12 culture medium at 37 ℃ for 24 h. The extracts were analyzed by flame atomic absorption spectrometer and were then diluted into different concentrations with culture medium. Finally, cytotoxicity of these original and diluted extracts on CHO-K1 cells was detected by cell counting kit-8 (CCK-8) assay.Results The viabilities of cells treated with the original extracts of six Cu-IUDs (TCu220C bulb, TCu220C, GCu220, GCu300, Yuangong Cu270 and Yuangong Ⅱ- 300) were all below 10% and the cupric ion concentrations in these extracts were 28.22 mg/L, 31.80 mg/L, 92.80 mg/L, 99.74 mg/L, 114.90 mg/L and 119.20 mg/L, respectively. After these original extracts were diluted, significant differences in cytotoxicity were exhibited. IUDs with larger copper surface areas (GCu300 and Yuangong Ⅱ-300) showed more cytotoxicity than those with smaller areas (GCu220 and Yuangong Cu270) respectively; When different shapes of Cu-IUDs were compared, TCu220C bulb showed lower cytotoxicity than TCu220C, and GCu300 exhibited higher toxicity than Yuangong Ⅱ-300; TCu220C displayed significantly lower cytotoxicity than GCu220 due to their differences in frames.Conclusion We presented evidence on the cytotoxic effects of copper ions released from Cu-IUDs on CHO-K1 cells and found that shape, frame together with copper surface area of Cu-IUDs had obvious influence on the cytotoxicity.展开更多
The Chinese Hamster Ovary (CHO K1) cell was used to express a targeted anti-cancer monoclonal antibody by optimizing the platform of the construction of production cell line in this study. The adherent CHO K1 was fi...The Chinese Hamster Ovary (CHO K1) cell was used to express a targeted anti-cancer monoclonal antibody by optimizing the platform of the construction of production cell line in this study. The adherent CHO K1 was first adapted to suspension culture in chemical defined medium. Then the glutamine synthetase (GS) vector was applied to construct a single plasmid to overexpress a monoclonal antibody IgG1. Post transfection, the produc- tion of cell pool was optimized by glutamine-free selection and amplification using various concentrations of methio- nine sulfoximine. The best cell pool ofCHO K1/IgG1 was used to screen the top single clone using the limiting dilution cloning. Finally, a high IgG1 production of 780 mg/L was obtained from a batch culture. This study demonstrated that the construction of high producing cell line, from gene to clone, could be completed within six month and the gene amplification improved protein production greatly.展开更多
基金supported by Public Service Platform of Science and Technology Projects in Data mining of contraceptives monitoring and research of risk assessment model(BM2012062)the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Objective To evaluate the cytotoxicity of six commonly used copper-bearing intrauterine devices (Cu-IUDs) on Chinese hamster ovary (CHO-K1) cells and to investigate the influence of frame, shape and copper surface area of Cu-IUDs on cell toxicity.Methods Cu-IUDs were incubated in 10% FBS-DMEM/F12 culture medium at 37 ℃ for 24 h. The extracts were analyzed by flame atomic absorption spectrometer and were then diluted into different concentrations with culture medium. Finally, cytotoxicity of these original and diluted extracts on CHO-K1 cells was detected by cell counting kit-8 (CCK-8) assay.Results The viabilities of cells treated with the original extracts of six Cu-IUDs (TCu220C bulb, TCu220C, GCu220, GCu300, Yuangong Cu270 and Yuangong Ⅱ- 300) were all below 10% and the cupric ion concentrations in these extracts were 28.22 mg/L, 31.80 mg/L, 92.80 mg/L, 99.74 mg/L, 114.90 mg/L and 119.20 mg/L, respectively. After these original extracts were diluted, significant differences in cytotoxicity were exhibited. IUDs with larger copper surface areas (GCu300 and Yuangong Ⅱ-300) showed more cytotoxicity than those with smaller areas (GCu220 and Yuangong Cu270) respectively; When different shapes of Cu-IUDs were compared, TCu220C bulb showed lower cytotoxicity than TCu220C, and GCu300 exhibited higher toxicity than Yuangong Ⅱ-300; TCu220C displayed significantly lower cytotoxicity than GCu220 due to their differences in frames.Conclusion We presented evidence on the cytotoxic effects of copper ions released from Cu-IUDs on CHO-K1 cells and found that shape, frame together with copper surface area of Cu-IUDs had obvious influence on the cytotoxicity.
文摘The Chinese Hamster Ovary (CHO K1) cell was used to express a targeted anti-cancer monoclonal antibody by optimizing the platform of the construction of production cell line in this study. The adherent CHO K1 was first adapted to suspension culture in chemical defined medium. Then the glutamine synthetase (GS) vector was applied to construct a single plasmid to overexpress a monoclonal antibody IgG1. Post transfection, the produc- tion of cell pool was optimized by glutamine-free selection and amplification using various concentrations of methio- nine sulfoximine. The best cell pool ofCHO K1/IgG1 was used to screen the top single clone using the limiting dilution cloning. Finally, a high IgG1 production of 780 mg/L was obtained from a batch culture. This study demonstrated that the construction of high producing cell line, from gene to clone, could be completed within six month and the gene amplification improved protein production greatly.