Expression of an immunocomplex consisting of Fc fragment fused with a consensus dengue envelope domain III in Saccharomyces cerevisiae

Objectives: To explore Saccharomyces cerevisiae as an expression platform for dengue oral immune complex vaccine development. Results: Molecular engineering was applied to create a fusion gene construct (scEDIII-PIGS) consisting of a yeast codon optimized sequence encoding for a synthetic consensus dengue envelope domain III (scEDIII) followed by a modified IgG Fc domain (PIGS). Northern blot showed transcription of the target gene, with a temporal expression pattern similar to those from previous work. Western blot showed assembly of various immune complexes from monomer to hexamer. Partial purification of scEDIII-PIGS was also attempted to demonstrate the feasibility of yeast system for immune complex vaccine development. Approximately 1 mg of scEDIII-PIGS can be produced from 1 l culture. Conclusion: This work demonstrated for the first time that various immunocomplex structures of our target protein could be efficiently produced in S. cerevisiae for future application in developing oral and injectable vaccines against various pathogens.