Vaccines for Porcine Parvovirus
Porcine parvovirus (PPV) is one of the major pathogens that cause swine reproductive disorder, characterized by stillbirth, mummification, embryonic death, infertility and delayed return to oestrus, causing huge economic losses in the global pig industry. The virus is widely distributed throughout the world, and only continuous vaccination can effectively prevent and control the occurrence and development of the disease. Therefore, the development of new and highly effective PPV vaccines is imperative.
Background of Porcine Parvovirus
PPV, an autonomously replicating member of the feline parvovirus subgroup of the genus Parvovirus within the family Parvoviridae, is a causative agent of reproductive failure in pregnant sows that is characterized by stillbirths, mummified fetuses, and early embryonic death. PPV has a single-stranded DNA genome of approximately 5,000 nucleotides surrounded by non-enveloped icosahedral particles of 20 nm in diameter, which are composed of three structural proteins: VP1, VP2, and VP3, of which VP2 is the major component. The capsid proteins VP1 and VP2 are translated by alternating RNA splicing, and VP3 is formed by proteolytic cleavage of the N-terminus of VP2. As a major component of the virus, the capsid VP2 protein can assemble into virus-like particles (VLPs) alone, which contains most of the B cell epitopes that play a key role in triggering neutralizing antibodies. Therefore, the VP2 protein is generally considered to be the main antigen of the PPV vaccine.
Vaccines for Porcine Parvovirus
- Inactivated vaccines
The inactivated vaccine is the most common type of PPV vaccine used in animals to prevent PPV infection today. The currently used whole-virus inactivated vaccines are based mainly on strain NADL2 and similar strains, isolated some 40 years ago. Inactivated PPV vaccines have deficiencies of specific cellular immune efficacy and failure to increase immunogenicity of weak antigen, and cannot effectively prevent and control PPV by humoral immunity. In order to avoid these defects, various efforts have been made in Creative Biolabs to enhance cellular immune responses of inactivated PPV vaccines, such as the addition of adjuvants, co-stimulating reagents and so on.
- Virus-like particles (VLPs) vaccines
The major structural protein, VP2 is the main target for neutralizing antibodies in PPV. When VP2 is expressed in large amounts, it assembles into VLPs that are similar in size and morphology to the original virions. VLPs are highly immunogenic and protect breeding sows from reproductive failure following virulent virus challenge. Therefore, PPV VLPs constitute a potential vaccine for prevention of parvovirus-induced reproductive failure. Compared to inactivated vaccines, VLPs have the following advantages: 1) VLPs do not require the propagation of the infectious virus, there is no risk of viral transmission or infection; 2) the production of VLPs can reach high levels, and production is cost-effective; 3) they are very stable in extreme environmental conditions.
Creative Biolabs has established a professional team, a series of mature platforms and a research and development system for decades. We guarantee to provide you with the best vaccines service against PPV. If you have any needs in this regard, please feel free to contact us.
All of our products can only be used for research purposes. These vaccine ingredients CANNOT be used directly on humans or animals.
