代谢相关酶过表达对CHO细胞瞬时表达anti-hLAG3的影响

Impact of metabolic enzymes overexpression on transient expression of anti-hLAG3 by CHO cells

摘要:

为提高CHO细胞重组蛋白表达量，对比研究了过表达代谢相关酶丙酮酸羧化酶 (PYC2)、苹果酸酶Ⅱ (MDH2)、丙氨酸转氨酶1 (ALT1)、鸟氨酸转氨甲酰酶 (OTC)、氨基甲酰磷酸合成酶Ⅰ (CPSⅠ) 和代谢相关蛋白牛磺酸转运蛋白 (TAUT) 及透明颤菌血红蛋白 (VHb) 对ExpiCHO-S瞬时表达anti-hLAG3的影响。结果表明，过表达上述7种蛋白均能不同程度提高抗体产量。其中，过表达OTC、CPSI、MDH2和PYC2分别能够使ExpiCHO-S抗体产量提高29.2%、27.6%、24.1%和20.3%。并且，过表达OTC和MDH2能够明显提高细胞培养初期的抗体生产速率，提前4 d达到与对照组相近的抗体产量。过表达OTC和MDH2对anti-hLAG3对抗原的亲和力基本无影响。大多数情况下，7种蛋白对细胞生长基本无影响。此外，过表达MDH2和ALT1同样能够提高H293T细胞的抗体产量。总的来说，代谢相关蛋白的过表达可以应用于瞬时表达系统，提高哺乳动物细胞的抗体产量。

Abstract:

To enhance recombinant protein production by CHO cells, We compared the impact of overexpression of metabolic enzymes, namely pyruvate carboxylase 2 (PYC2), malate dehydrogenase Ⅱ (MDH2), alanine aminotransferase Ⅰ (ALT1), ornithine transcarbamylase (OTC), carbamoyl phosphate synthetase Ⅰ (CPSⅠ), and metabolism related proteins, namely taurine transporter (TAUT) and Vitreoscilla hemoglobin (VHb), on transient expression of anti-hLAG3 by ExpiCHO-S. Overexpression of these 7 proteins could differentially enhance antibody production. OTC, CPSI, MDH2, and PYC2 overexpression could improve antibody titer by 29.2%, 27.6%, 24.1%, and 20.3%, respectively. Specifically, OTC and MDH2 could obviously improve early-stage antibody production rate and the culture period was shortened by 4 days compared with that of the control. In addition, OTC and MDH2 had little impact on the affinity of anti-hLAG3. In most cases, overexpression of these proteins had little impact on the cell growth of ExpiCHO-S. MDH2 and ALT1 overexpression in H293T cells could also improve antibody production. Overall, overexpression of enzymes involved in cellular metabolism is an effective tool to improve antibody production in transient expression system.