Improvement of the Yield of Therapeutic HPV DNA Vaccine by Exponential Feeding Combined with Temperature Rise Fermentation
Cervical cancer is the fourth most common cancer in women worldwide. HPV vaccines currently on the market are all pro-phylactic vaccines,which have no therapeutic effect on people already infected with HPV. HPV infection rates remain high. Scientists are developing therapeutic HPV vaccines that induce cellular immunity to kill cells infected with HPV in rencent years. Therapeutic HPV DNA vaccines are favored for its low cost and good stability. In order to reduce the cost of therapeutic HPV DNA vaccines,high density fermentation of E. coli is used. This study used a therapeutic HPV DNA vaccine,which is a DNA plasmid with heat-sensitive property. Firstly,E. coli with DNA plasmid was cultured in shake. After culture at 30 ℃ for a certain time,the temperature was raised to 37 ℃ or 42 ℃. It was found that the plasmid yield of the group with temperature rising to 42 ℃ was significantly higher than that of the group with temperature rising to 37 ℃. Further research was conducted to culture E. coli by fermentation. After culture at 30 ℃ for a certain time,the temperature was raised to 42 ℃ to further improve the copy number of the plasmid,and to explore the influence of temperature rise fer-mentation strategy combined with constant feeding or exponential feeding on the yield of DNA plasmid. The results showed that compared with constant feeding,exponential feeding could significantly increase the yield of DNA plasmid combining with the temperature rise fer-mentation strategy,from 125.76 mg·L-1 to 619.94 mg·L-1. The therapeutic HPV DNA vaccine obtained by fermentation is highly expressed in 293T cells and can induce a strong HPV specific cellular immune response in vivo. The exponential feeding combined with temperature rise fermentation strategy also has reference significance for the fermentation of other DNA plasmids,and can provide refer-ence on high-quality DNA plasmids for cell products such as CAR-T and RNA related products.
HPVTherapeutic HPV DNA vaccineHeat-sensitive plasmidTemperature rise fermentation strategyConstant feedingExponential feeding
万方数据
维普
