Comparison of Internal Ribosome Entry Site (IRES) and Furin-2A (F2A) for Monoclonal Antibody Expression Level and Quality in CHO Cells

Steven Ho (1) , Muriel Bardor (2, 1) , Bin Li (1) , Jia Juan Lee (1) , Zhiwei Song (1) , Yen Wah Tong (3) , Lin-Tang Goh (1) , Yuansheng Yang (1, 4)

1 A*STAR - Agency for science, technology and research [Singapore]
2 Glyco-MEV - Laboratoire de Glycobiologie et Matrice Extracellulaire Végétale
3 NUS - National University of Singapore
4 Nanyang Technological University [Singapour]

Four versions of tricistronic vectors expressing IgG1 light chain (LC), IgG1 heavy chain (HC), and dihydrofolate reductase (DHFR) in one transcript were designed to compare internal ribosome entry site (IRES) and furin-2A (F2A) for their influence on monoclonal antibody (mAb) expression level and quality in CHO DG44 cells. LC and HC genes are arranged as either the first or the second cistron. When using mAb quantification methods based on the detection antibodies against HC Fc region, F2A-mediated tricistronic vectors appeared to express mAb at higher levels than the IRES-mediated tricistronic vectors in both transient and stable transfections. Further analysis revealed that more than 40% of products detected in stably transfected pools generated using the two F2A-mediated tricistronic vectors were aggregates. LC and HC from the F2A stably transfected pools were not properly processed, giving rise to LC+F2A+HC or HC+F2A+LC fusion proteins, LC and HC polypeptides with F2A remnants, and incorrectly cleaved signal peptides. Both IRES-mediated tricistronic vectors express mAb with correct sizes and signal peptide cleavage. Arrangement of LC as the first cistron in the IRES-mediated tricistronic vectors exhibits increased mAb expression level, better growth, and minimized product aggregation, while arrangement of HC as first cistron results in low expression, slower growth, and high aggregation. The results obtained will be beneficial for designing vectors that enhance mAb expression level and quality in mammalian cells.

Domaines: Polymères; Amélioration des plantes; Interactions cellulaires [q-bio.CB]; Biochimie [q-bio.BM]; Biologie moléculaire; Génomique, Transcriptomique et Protéomique [q-bio.GN]; Réseaux moléculaires [q-bio.MN]; Phytopathologie et phytopharmacie; Biotechnologies; Gamétogenèse; Organisation et fonctions cellulaires [q-bio.SC]

Steven Ho, Muriel Bardor, Bin Li, Jia Juan Lee, Zhiwei Song, et al.. Comparison of Internal Ribosome Entry Site (IRES) and Furin-2A (F2A) for Monoclonal Antibody Expression Level and Quality in CHO Cells. PLoS ONE, 2013, 8 (5), pp.e63247. ⟨10.1371/journal.pone.0063247⟩. ⟨hal-01843946⟩