Servesto provides virus-like particles (VLPs) containing high concentrations of specific membrane proteins in their native conformation. VLPs capture conformationally-intact membrane proteins directly from the cell surface, enabling these complex proteins to be manipulated as soluble proteins. Our VLPs are produced with specified membrane proteins on a custom basis, or are available from a selected catalog of ReadyVLPs. Sample kits are also available for purchase for preliminary application testing.
Virus-like particles (VLPs) have evolved to become a widely accepted technology, especially in the field of vaccinology. In fact, some VLP-based vaccines are currently used as commercial medical products, and other VLP-based products are at different stages of clinical study. Several remarkable advantages have been achieved in the development of VLPs as gene therapy tools and new nanomaterials. In recent years, the technologies develop very fast that are used to characterize the structural integrity, stability, and components, including the encapsidated nucleic acids, of newly synthesized VLPs. Moreover, some of the modifications that are required to construct VLP-based carriers of viral origin with defined properties can be provided.
VLPs have been produced from components of a wide variety of virus families including Parvoviridae (e.g. adeno-associated virus), Retroviridae (e.g. HIV), Flaviviridae (e.g. Hepatitis C virus) and bacteriophages (e.g. AP205). VLPs can be produced in multiple cell culture systems including bacteria, mammalian cell lines, insect cell lines, yeast and plant cells.
The understanding of self-assembly of VLPs was once based on viral assembly. This is rational as long as the VLP assembly takes place inside the host cell (in vivo), though the self-assembly event was found in vitro from the very beginning of the study about viral assembly. Study also reveals that in vitro assembly of VLPs competes with aggregation and certain mechanisms exist inside the cell to prevent the formation of aggregates while assembly is ongoing.
Attaching proteins, nucleic acids, or small molecules to the VLP surface, such as for targeting a specific cell type or for raising an immune response is useful. In some cases, a protein of interest can be genetically fused to the viral coat protein. However, this approach sometimes leads to impaired VLP assembly and has limited utility if the targeting agent is not protein-based. An alternative is to assemble the VLP and then use chemical crosslinkers, reactive unnatural amino acids or SpyTag/SpyCatcher reaction in order to covalently attach the molecule of interest. This method has shown to be very effective at directing the immune response against the attached molecule, thereby inducing high levels of neutralizing antibody titers and breaking immune self-tolerance.
VLPs provide an alternative to living cells, membrane preparations, and detergent-solubilized proteins by offering concentrated membrane proteins in their native conformation. VLPs are used throughout drug and antibody discovery and characterization, and have been integrated into a wide variety of existing platforms.