Vaccines for Parvovirus B19
Parvovirus B19 is an important human pathogen causing erythema infectiosum, transient aplastic crisis in individuals with underlying hemolytic disorders and hydrops fetalis. The capsid proteins VP1 and VP2 of parvovirus are very important for viral infection, and VP2 can self-assemble into viral particles (VLPs), but VP1 cannot. Virus-like particle vaccines consisting of VP2 or VP1 play a very important role in preventing and controlling infection of parvovirus B19
Background of Parvovirus B19
Parvovirus B19, discovered serendipitously in 1974, is a non-enveloped virus with a single-stranded DNA genome and is known to be pathogenic in humans. The two proteins, VP1 and VP2, form the parvovirus B19 capsid at a ratio of approximately 1:20. VP1 and VP2 are produced by alternative splicing such that they share a common C-terminal region but VP1 contains a unique 226 amino acid at N-terminus region. This N-terminal extension contains a phospholipase A2 (PLA2) domain, which is essential for viral infectivity. Like many other non-enveloped viral structural proteins, parvovirus B19 VP2 spontaneously forms VLPs, but the parvovirus B19 VP1 alone cannot.
In healthy individuals, parvovirus B19 causes erythema infection, commonly referred to as the fifth disease, a child rash which can manifest as an arthralgia syndrome in adults. In individuals with underlying hemolytic disorders, parvovirus B19 infection causes transient aplastic crisis (TAC), a temporary cessation of red blood cell production with severe worsening of anemia, which is occasionally fatal. In immunosuppressed individuals, parvovirus B19 can persist and cause severe anemia and pure red cell aplasia.
Vaccines for Parvovirus B19
VLPs are biological nanoparticles identical to the natural virions but do not contain genetic material. VLPs are suitable for analyzing viral infection mechanisms, vaccine production, tissue-specific drug delivery, and bio-nanomaterials. Therefore, VLPs from this virus have great potential in medicine and diagnosis. The production of self-assembled VLPs vaccines currently derived from B19 is typically performed in eukaryotic expression systems.
VLPs in Saccharomyces cerevisiae
The VLPs vaccine is produced by expressing viral proteins VP1 and VP2 at a fixed ratio from a single differentially regulated, bicistronic plasmid in Saccharomyces cerevisiae. The dual expression strategy improves the control of the VP1 / VP2 ratio in the VLPs. The vaccine also includes point mutations in VP1 that abolish its phospholipase A2 activity, which is a potential cause of adverse reactions observed in early clinical trials. The resulting homogeneity of VLPs facilitates purification to a very low contaminant level.
VLPs in the baculovirus-insect system
The parvovirus B19 VLP vaccine candidates are produced by co-infection of insect cells with two baculoviruses, one expressing wild-type VP1 and the other expressing VP2 in which the 2 capsid proteins self-assemble into VLPs. The relative amounts of expressed VP1 and VP2 are adjusted by manipulating the ratio of the two baculoviruses used for infection. The capsid is immunogenic in a variety of animals and humans, triggering a neutralizing antibody response. Empty capsids are enriched by manipulation of multiple infections of recombinant insect viruses, which are particularly effective in promoting neutralizing antibody responses.
Our Services for Vaccines of Parvovirus B19
- Providing a variety of expression systems
- Production and purification of VLPs
- Evaluation of immune effects
- Statistical analysis
With a variety of mature and comprehensive platforms and technologies, for the evaluation and improvement of vaccine development, Creative Biolabs is dedicated to providing the best services for vaccines against Parvovirus B19. If you have any needs in this regard, please contact us as soon as possible.
All of our products can only be used for research purposes. These vaccine ingredients CANNOT be used directly on humans or animals.
