Improved expression of secretory and trimeric proteins in mammalian cells via the introduction of a new trimer motif and a mutant of the tPA signal sequence

• Published in: Applied microbiology and biotechnology Vol. 91; no. 3; pp. 731 - 740
• Main Authors: Wang, Jia-Ye, Song, Wen-Ting, Li, Yan, Chen, Wen-Jiang, Yang, Dan, Zhong, Guo-Cai, Zhou, Hai-Zhou, Ren, Cai-Yun, Yu, Hao-Tong, Ling, Hong
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01.08.2011; Springer; Springer Nature B.V
• Subjects: Amino Acid Motifs - immunology; Amino Acid Sequence; Analysis; Antigens; Applied Genetics and Molecular Biotechnology; Bats; Biological and medical sciences; Biomedical and Life Sciences; Biotechnology; Cells; Deoxyribonucleic acid; DNA; Enzyme-Linked Immunosorbent Assay; Fundamental and applied biological sciences. Psychology; gag Gene Products, Human Immunodeficiency Virus - genetics; gag Gene Products, Human Immunodeficiency Virus - immunology; gag Gene Products, Human Immunodeficiency Virus - metabolism; Gene amplification; Genetic vectors; Glycoproteins; HEK293 Cells; Hemagglutinin Glycoproteins, Influenza Virus - genetics; Hemagglutinin Glycoproteins, Influenza Virus - immunology; Hemagglutinin Glycoproteins, Influenza Virus - metabolism; HIV - genetics; HIV - metabolism; Humans; Immunogenicity; Influenza; Influenza A Virus, H3N2 Subtype - genetics; Influenza A Virus, H3N2 Subtype - metabolism; Life Sciences; Mammals; Microbial Genetics and Genomics; Microbiology; Multiprotein Complexes; Mutation; Peptides; Plasmids; Protein Sorting Signals - genetics; Protein Structure, Secondary; Proteins; Recombinant Fusion Proteins - genetics; Recombinant Fusion Proteins - immunology; Studies; Tissue plasminogen activator; Tissue Plasminogen Activator - genetics; Tissue Plasminogen Activator - immunology; Vaccines; Vaccines, DNA - immunology; Vaccines, Subunit - immunology; Vectors (Biology); China; Signal peptide; Tissue plasminogen activator (tPA); Protein expression; Mammalian cell; Trimer motif; Leader peptide; Serine endopeptidases; Enzyme; Trimer moti; t-Plasminogen activator; Peptidases; Vertebrata; Mammalia; Secretory protein; Hydrolases; Mutation
• ISSN: 0175-7598; 1432-0614
• DOI: 10.1007/s00253-011-3297-0

Ideal immunogenicity in antigens is a prerequisite to eliciting a sufficiently strong immune and memory response via either DNA or protein vaccines. To improve immunogenicity, efforts have focused on high-level expression of target proteins and on maintaining their natural conformations. In the present work, two trimer motifs (MTQ and MTI) were designed and introduced into a plasmid vector with the tissue plasminogen activator signal peptide (tPA-SP). Next, we examined the efficacy and the efficiency of the two motifs as well as the introduction of tPA-SP and its mutant forms, 22P/A and 22P/G, in facilitating the secretory expression of trimeric proteins in mammalian cells. We found that both trimer motifs could produce the target protein in a trimeric form at a high level. Introduction of tPA-SP 22P/A markedly increased the secretory expression level. The combination of the trimer motif, MTQ, and the signal peptide, 22P/A, may serve as a universal mammalian vector for producing trimeric proteins in vaccine development.