Product Support
      Back to home
      1. Resource Center
      2. Product Support

      Virus-Like Particle (VLP) Antigens: FAQs

      Frequently Asked Questions Regarding VLP Proteins

      1. What are VLP-Displayed Antigens?
        1. Virus-like particles (VLPs) are small nanoparticles made from the shell protein of a virus. They form when one or more of these shell proteins automatically come together. VLPs do not contain viral infectious genomes, so they are relatively safe to use in production operations.
      2. What are the benefits of VLP-Displayed Antigens? 
        1. Virus-Like Particles (VLPs) are good at boosting the immune response. This makes them useful for immunization, especially with antigen targets that are usually present in low amounts or don’t trigger a strong immune reaction by themselves. They also allow for soluble expression of multipass transmembrane proteins in their natural configuration.
      3. Can GPCR-VLP be used to enrich positive B cells after immunization with GPCR- VLP? 
        1. Yes, you may use the biotinylated GPCR-VLP co-staining with SA fluorescence to enrich the B cells.
      4. What are the expression platforms for producing VLPs?
        1. Mammalian, bacterial, yeast, and insect cells
      5. Where is the biotin label on the VLP products? 
        1. The biotin label on our VLP products is on the membrane, not on the target protein. 
      6. What is the purpose of the biotin label for VLPS?
        1. The purpose of the biotin label is for the immobilization of the VLP-displayed proteins to SA chips for SPR purposes. 
      7. Is it possible to use suspension cell lines for pseudotyped VLPs?
        1. Yes, please give us more information about this!
      8. What is the recommended dosage for VLPS? 
        1. Since VLP-displayed antigens are super antigens, you only need 25-50 ug/dose, for a total of 4 to 5 doses, for mice immunizations. Per mouse, we recommend you would need about 0.25 mg per mouse. 
      9. What is the expected quantity of proteins in each VLP? 
        1. The VLP particle displaying the transmembrane proteins are a randomly formed complex, so there are variations of copy numbers of the capsids and are different from particle to particle. This makes it so that we cannot calculate the molecular weight of the full VLP. 
      10. What are the different applications for VLPS? 
        1. VLPs can be used for ELISA, SPR, Immunization, CAR-T positive rate detection, and PK/PD analysis
      11. Can KACTUS make Vpx-VLP particles (enveloped using Vsv-g) for cell culture treatment applications?
        1. At this moment, we have chosen not to pursue this as we specialize in transmembrane proteins expressed in VLP mainly for immunization and screening purposes.