title: Clinical, virological, immunological and pathological evaluation of four porcine circovirus type 2 vaccines.
abstract: The objective of this study was to rigorously compare the efficacy of four porcine circovirus type 2 (PCV2) vaccines of varying antigen type and dose under experimental conditions based on well-defined clinical (average daily weight gain [ADWG]), virological (evidence of viraemia), immunological (presence of PCV2-specific neutralising antibodies [NA], interferon-γ-secreting cells [IFN-γ-SCs], and CD3(+) and CD4(+) T cell subsets), and pathological (lymphoid lesion and PCV2 antigen score) criteria. A total of 60, 3-week old piglets were assigned to six groups of 10/group and were vaccinated either with 1/4 commercially available one-dose vaccines or were not vaccinated. At 7 weeks of age, vaccinated and control animals were inoculated intranasally with 2 mL of PCV2b. All pigs were euthanased and subjected to post-mortem examination at 25 weeks of age. From 9 to 16 weeks of age, the ADWG of vaccinated animals was significantly higher than that of non-vaccinates. Significant (P<0.05) differences were observed between vaccinated and positive control groups in the quantity of log-transformed PCV2b DNA in the blood and nasal swabs, log-transformed NA titres, and PCV2-specific IFN-γ-SCs at 0, 7, 14, 21, and 42 days post challenge (dpc). The proportion of CD4(+) cells at 7 and 14 dpc was also significantly different between vaccinated and control pigs (P<0.05). The histopathological lesions and PCV2-antigen scores in the lymph nodes were significantly lower (P<0.05) in vaccinated animals. All four vaccines were found to be highly efficacious in controlling experimental PCV2 challenge based on this range of criteria.
authors.affiliation: Department of Veterinary Pathology, College of Veterinary Medicine, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151-742, Republic of Korea.
authors.forename: Hwi Won
authors.initials: HW
authors.lastname: Seo
authors.affiliation: Department of Veterinary Pathology, College of Veterinary Medicine, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151-742, Republic of Korea.
authors.forename: Kiwon
authors.initials: K
authors.lastname: Han
authors.affiliation: Department of Veterinary Pathology, College of Veterinary Medicine, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151-742, Republic of Korea.
authors.forename: Changhoon
authors.initials: C
authors.lastname: Park
authors.affiliation: Department of Veterinary Pathology, College of Veterinary Medicine, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151-742, Republic of Korea. Electronic address: swine@snu.ac.kr.
authors.forename: Chanhee
authors.initials: C
authors.lastname: Chae
mesh_terms: D000818:Animals; D057134:Antibodies, Neutralizing / Q000097:blood; D000914:Antibodies, Viral / Q000097:blood; D018173:Circoviridae Infections / Q000276:immunology / Q000517:prevention & control / Q000662:veterinary* / Q000821:virology; D017925:Circovirus / Q000276:immunology*; D004279:DNA, Viral / Q000097:blood; D007111:Immunity, Cellular; D056724:Immunity, Humoral; D007371:Interferon-gamma / Q000276:immunology; D053570:Porcine Postweaning Multisystemic Wasting Syndrome / Q000276:immunology / Q000517:prevention & control* / Q000821:virology; D056910:Republic of Korea; D013552:Swine; D014611:Vaccination / Q000662:veterinary; D015164:Vaccines, Inactivated / Q000276:immunology; D014765:Viral Vaccines / Q000276:immunology*; D014766:Viremia / Q000276:immunology / Q000517:prevention & control / Q000662:veterinary / Q000821:virology
chemical_list: D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D004279:DNA, Viral; D015164:Vaccines, Inactivated; D014765:Viral Vaccines; D007371:Interferon-gamma
keywords: PCV-associated disease; Porcine circovirus (PCV) type 2; Post-weaning multisystemic wasting syndrome; Vaccine