过表达蛋白合成与分泌相关蛋白提高CHO细胞anti- hLAG3产量

Enhancement of anti- hLAG3 production in CHO cells by overexpression of proteins involved in protein biosynthesis and secretion

对比研究了过表达蛋白合成与分泌途径中的20种蛋白对瞬时表达细胞(ExpiCHO-S细胞)表达anti-hLAG3产量的影响,考察了转录因子XBP1s对ExpiCHO-S细胞生长、抗体产量和抗体亲和力的影响。结果表明,当所研究蛋白的表达质粒与anti-hLAG3质粒以1∶4的质量比共转染时, XBP1s能够使抗体产量提高约30%, GADD34、NFKBIz、CERT、C/EBPα和mTOR的过表达则会明显降低抗体产量,其他14种蛋白对抗体产量的影响较小。随着XBP1s共转染比例的增加,其对anti-hLAG3生产的促进作用增强,当共转染比例提高到60%时,相对于共转染比例为60%的EGFP,可使转染后168 h的抗体产量提高到2.1倍。此外,XBP1s的过表达对活细胞密度和细胞活率以及抗体亲和力的影响均较小。以上结果表明XBP1s可作为细胞工程的一个有效靶标用于提高CHO细胞重组蛋白的生产性能。

The effects of overexpression of 20 proteins involved in protein biosynthesis and secretion pathways on the anti-hLAG3 titer in the transient expression cells(ExpiCHO-S) have been compared. The effects of transcription factor XBP1 s on cell growth, antibody titer, and antibody affinity were specifically studied. The results showed that when plasmids of the studied proteins and anti-hLAG3 were co-transfected with a mass ratio of 1∶4, the presence of XBP1 s increased the antibody production by about 30%. Furthermore, overexpression of GADD34, NFKBIz, CERT, C/EBPα and mTOR obviously reduced antibody production. The other 14 proteins had little impact on antibody production. In addition, the promotion effect of XBP1 s on anti-hLAG3 production increased as the transfection ratio of XBP1 s increased. When the transfection ratio of XBP1 s was increased to 60%, the antibody production at 168 h after transfection was increased to 2.1-fold when compared with a 60% transfection ratio of EGFP. The overexpression of XBP1 s had little effect on viable cell density and viability, or the affinity of antibodies. The results indicated that XBP1 s can be used as an effective target for cell engineering to improve the recombinant protein production performance of CHO cells.