小中大5. 讨 论
我们现在正在考虑替换工业用培养基中的动物来源的成份。已经证实CHO细胞有可能在完全限定化学成份、不含动植物来源蛋白质、多肽或水解产物的培养基中生长。与无血清培养基(CHO-S-SFM II)和无蛋白、未限定的培养基(CHO III PFM)相比,在CD CHO培养基的批量培养能获得高密度的细胞。在到达细胞密度的峰值后,CD CHO培养基中培养的DHFR扩增的rCHO细胞系出现高表达水平。已经证实丁酸钠是细胞生长的强抑制剂,还能促进蛋白质合成〔6〕。其他人也证实多克隆抗体〔7〕和重组蛋白质〔8、9〕的表达水平在加入丁酸钠之后提高。在我们的研究中,通过加入丁酸钠成功限制了细胞的生长并增强了rCHO细胞的rß-Gal表达水平。然而,浓度和加入时间对蛋白质表达的优化也非常重要。用5L的生物反应器能在CD CHO中大规模培养。我们利用限定化学成份的培养基培养CHO细胞的实验表明您能够有更好的选择,用以替换含血清培养基、无血清或无蛋白但没有限定化学成份的培养基配方。
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