Virus-Like Particle: Structure, Characteristics and Application in Vaccine

Virus-like particles (VLPs) are a group of subunit vaccines, which due to a stronger protective immunogenicity, are distinguished from soluble recombinant antigens. Like native viruses, virus-like particles can be both enveloped and non-enveloped. They are formed from the expression of one or more viral structural proteins in a heterologous system. Depending on the complexity of the VLP, the proteins can be produced in prokaryotic or eukaryotic expression systems, or in certain cases, they can be manufactured and assembled in the cell-free conditions. Virus-like particles can be produced in a range of cell culture systems, including mammalian cell lines, insect cells, yeast, plant cells and cell-free conditions. To date, a wide range of VLP-based vaccine candidates against viral, bacterial, parasitic, and fungal pathogens, as well as non-infectious diseases, have been produced in various expression systems. Some of VLPs have entered clinical development and few of them have licensed and commercialized.