CPV Vaccine Development

CPV Vaccine Development

Despite widespread vaccination of dogs, canine parvovirus (CPV) remains the leading cause of death in dogs. Since the spread of CPV around the world, several variants have emerged, including CPV-2, CPV-2a, CPV-2b, CPV-2c, Neo-CPV-2a, Neo-CPV-2b, CPV-2c(a) and CPV-2c(b). Among them, CPV-2 is the pathogen of severe gastroenteritis in dogs, replicates in lymph nodes, spreads to the gastrointestinal tract with the blood, and spreads through the fecal-oral route.

Overview of CPV

CPV-2 belongs to the Parvoviridae family, Parvovirinae subfamily, Protoparvovirus genus and Carnivore Protoparvovirus 1 species. CPV-2 is a small non-enveloped virus containing a 5323 nucleotide (nt) single-stranded (ss) negative DNA genome. The DNA molecule consists of two open reading frames (ORFs), ORF1 and ORF2. ORF1 is located at the 3' end of the genome and encodes non-structural proteins NS1 and NS2. ORF2 is located at the 5' end of the genome and encodes three structural proteins: VP1, VP2 and VP3. VP2 is a truncated form of VP1 and VP3 is formed by post-translational proteolytic cleavage of the amino-terminal 15-20 amino acids (aa) of VP2. VP2 is a major determinant of host range and is subject to antibody-mediated selection. In addition, VP2 protein is highly variable and thus is a major target for CPV-2 characterization and phylogenetic studies.

Genetic organization of CPV-2. (Tuteja D, et al., 2022)

CPV Vaccine

Although the emergence of new CPV-2 variants may negatively impact currently available vaccines, vaccination to protect dogs from CPV-2 infection is very important and is the most effective measure to control virus transmission and prevent clinical infection.

• Inactivated Vaccines
  Inactivated vaccines are recommended only for exotic animals and pregnant bitches because of their low immunogenicity and require repeat immunizations and annual booster immunizations. In addition, in puppies under 12 weeks of age, inactivated vaccines were more likely to cause immune failure than modified live virus (MLV) vaccines, likely due to the greater replication capacity of MLV to cover residual maternally derived antibodies (MDA).
• MLV Vaccines
  Only two CPV types are included in the CPV MLV vaccine formulation, the original CPV-2 strain and its variant CPV-2b.

MLV vaccines are widely used because they induce robust, long-lasting immunity by replicating within the host without producing overt tissue damage or clinical symptoms.

• VLP Vaccines
  Virus-like particles (VLPs) are obtained by self-assembly of viral structural proteins produced in expression systems (bacteria, yeast, insects, plants, etc.). The outstanding advantages of VLPs vaccines are high safety and immunogenicity, and they can open up new frontiers in vaccine development. VP2 is the main capsid protein of CPV, and a VLP vaccine for CPV-2 can be developed based on VP2.

How We Can Help

As an expert in building VLPs from VLPlant^TM platform, CD BioSciences uses its expertise to help our clients develop CPV vaccines. We are good at customizing our services according to the needs of our clients. Please contact us if you are interested.

Our capabilities include but are not limited to:

Quote and Ordering

Reference

1. Tuteja D.; et al., Canine parvovirology - A brief updated review on structural biology, occurrence, pathogenesis, clinical diagnosis, treatment and prevention. Comp Immunol Microbiol Infect Dis. 2022, 82: 101765.