TNFR-Fc is an important fusion protein that has great potential in therapeutic and diagnostic applications. We developed an efficient fed-batch process for GS-CHO cells to produce TNFR-Fc. The rationale of this fed-batch process relies on the supply of sufficient nutrients to meet the requirements of cell metabolism. The optimal feed medium was designed through ration design. A metabolically responsive feeding strategy was designed and dynamically adjusted based on the residual glucose concentration determined off-line. In this process, the maximal viable cell density and antibody concentration reached above 9.4x10(6) cells/mL and 207 mg/L, respectively. Compared with the batch process, the newly developed fed-batch process increased the cell yield by 3.4 fold and the final antibody concentration by 3 fold. This fed-batch process would therefore facilitate the production of therapeutic antibody by GS-CHO cells.
Animals ; CHO Cells ; Cell Culture Techniques ; methods ; Cricetinae ; Cricetulus ; Culture Media ; Etanercept ; Glucose ; analysis ; Immunoglobulin G ; biosynthesis ; genetics ; Receptors, Tumor Necrosis Factor ; biosynthesis ; genetics ; Recombinant Fusion Proteins ; biosynthesis ; genetics

OBJECTIVE To investigate the effects of different drying methods on the index components in wine-processed Cornus officinalis so as to optimize drying method.METHODS After processed with wine， C. officinalis decoction pieces were dried with different drying methods （blast drying， far infrared drying， microwave drying， freeze drying， sun drying， shade drying and combined drying）. The contents of 5 components such as gallic acid in wine-processed C. officinalis were determined by high- performance liquid chromatography. The contents of total flavonoids in wine-processed C. officinalis were determined by chromogenic method. Analytic hierarchy process was used to evaluate the effects of different drying methods on the contents of components in C. officinalis.RESULTS The contents of gallic acid， 5-hydroxymethylfurfural， monoside， loganin， cornuside and total flavonoids in 22 batches of wine-processed C. officinalis were 1.043 8-1.563 8， 0.648 5-2.358 8， 5.031 0-10.305 7， 6.681 2- 7.534 2， 0.986 5-1.148 8 and 33.657 2-50.741 5 mg/g， respectively. The comprehensive scoring results of analytic hierarchy process showed that the comprehensive score of each component in C. officinalis dried by microwave at 75 ℃ was higher ， followed by blast drying at 60 ℃ and far infrared drying at 60 ℃ .CONCLUSIONS The wine-processed C. officinalis could be dried by microwave drying at 75 ℃， blast drying at 60 ℃ or far infrared drying at 60 ℃.