Construction of Fusion Expression Vector for Human IgG Fc Tag and Expression of H5 HA1 Fusion Protein

Objective To construct a fusion expression vector for human IgG Fc tag and express and purify H5 HA1 fusion protein.Methods IL-2 signal peptide and human IgG Fc fragment were inserted into vector pCAGGS in turn to construct a fusion expression vector for human IgG Fc tag.H5 HA1 gene was cloned into fusion expression vector pCAGGS-F-IL-2 / Fc for human IgG Fc tag,and the constructed recombinant plasmid was transiently transfected to 293T cells for expression of fusion protein.The expressed product was purified by one-step Protein G affinity chromatography.Results Restriction analysis and sequencing proved that the fusion expression vector for human IgG Fc tag was constructed correctly,and HA1-Fc fusion protein,with a relative molecular mass of about 75 000,was successfully expressed in 293T cells in secretory form in 293T cells.The expression level of fusion protein in the cells 72 and 96 h after transfection reached peak values.The purified fusion protein reached a purity of more than 90%,and the recombinant protein content in cell culture was 1.63 μg / ml.Conclusion The fusion expression vector for human IgG Fc tag was successfully constructed,and HA1-Fc fusion protein was expressed and purified,which laid a foundation of study on invasion and immune mechanism of influenza virus.