Canine parvovirus (CPV) remains a leading infectious cause of death in canines, especially in young puppies. Though vaccination is being carried out regularly, immunization failures occur, and puppies may be exposed to infection. Virus-like particles (VLPs) act like a subunit vaccine, mimicking the structure of authentic viruses. Therefore, VLPs have the potential to be used as vaccine candidates. Since Viral Protein 2 (VP2), a major structural protein of CPV, is the crucial antigen for CPV, the purpose of this study was to produce a recombinant VP2 of new canine parvovirus-2a using the baculovirus expression system in SF9 insect cells. The results revealed that recombinant VP2 assembles to form VLPs with antigenic properties similar to those of natural CPV, the recombinant VLP can produce a hemagglutination assay (HA) titer (1:210) in SF9 cells. Expression of the recombinant 6-His-tagged VP2 in SF9 cells was confirmed by western blotting. These findings suggest that the recombinant VP2 expressed in this study could be used as an efficient subunit vaccine against CPV infection.

Viral protein 2 (VP2), which is the structural protein of parvovirus, can produce virus-like particles (VLPs) by a self-assembly process in vitro, making VLPs attractive vaccine candidates. VP2 of canine parvovirus (CPV) is responsible for neutralizing antibodies in immunized animals. In this study, VP2 protein of canine parvovirus-2c was expressed using a baculovirus expression system and assembled into parvovirus-like particles in insect cells. The results show that VP2 proteins assembled into virus-like particles (VLPs) with antigenic properties similar to those of natural CPV and a high hemagglutination (HA) titer (1:27). The recombinant 6-His-tagged VP2 protein with a molecular mass of about 65 kDa was detected by anti-His antibody and anti-PPV serum. This study provides a foundation for the application of VP2 protein in the clinical diagnosis of CPV and in the vaccination against CPV.

Viral protein 2 (VP2) of porcine parvovirus (PPV) is responsible for inducing neutralizing antibodies in immunized animals. It is the major viral structural protein. In this study, novel subunit vaccines against PPV based on virus-like particles (VLPs) formed from VP2 proteins (PPV 13-7 Korean strain) were expressed in an insect baculovirus cell system and purified using Ni-NTA affinity column chromatography. These VP2 proteins assembled into virus-like particles (VLPs). They showed antigenic properties similar to those of natural PPV. In addition, they showed high hemagglutination (HA) titers (211 for PPV 13-7 Korean strain). This study provides a foundation for the application of the difference immunization of recombinant protein in the diversity of PPV VP2 genes and in vaccination against PPV in the future.

Canine parvovirus type-2 (CPV-2) has been reported worldwide as the main agent associated with acute hemorrhagic enteritis, resulting in high morbidity, especially in young dogs. CPV-2 has three genetic variants, 2a, 2b, and 2c. Here, we report three cases of canine parvovirus enteritis associated with CPV-2a (2 samples) and -2c (1 sample) infections that occurred in three young dogs suffering from enteritis. Isolates from dog diarrheic fecal samples were sequenced by polymerase chain reaction (PCR) and identified as two types of CPV-2a and one type of CPV-2c. This work constitutes the first isolation and genetic characterization of CPV-2c in the Republic of Korea.