title: Analysis of the acute-phase protein response in pigs to clinical and subclinical infection with H3N2 swine influenza virus.
abstract: BACKGROUND
  Swine influenza (SI) is a contagious, important respiratory disease. Diagnosis of SI is based on the clinical signs, confirmed by the detection of viral RNA or specific antibodies. However, the infection is much more frequent than the disease.
  
  
  OBJECTIVE
  The aim of study was to investigate the kinetics of acute-phase protein (APP) response during subclinical and clinical influenza in pigs. The utility of APP measurements in identification of infected animals was also evaluated.
  
  
  METHODS
  Twenty-eight piglets were used. C-reactive protein (CRP), haptoglobin (Hp), serum amyloid A (SAA) and pig major acute-phase protein (Pig-MAP) concentrations in serum were measured using commercial ELISAs.
  
  
  CONCLUSIONS
  No relevant clinical signs were observed in intranasally infected pigs. In contrast, coughing, nasal discharge, and fever were observed in pigs infected intratracheally. All infected pigs exhibited specific antibodies in the serum at 10 dpi, and viral shedding was confirmed. The concentrations of CRP, Hp and SAA were significantly increased after infection. The level of Pig-MAP remained constant during subclinical and clinical infection. The concentrations of CRP, Hp and SAA were higher in pigs with clinical disease. Although not specific, strategic APP measurements may reveal ongoing clinical and subclinical infection. A close relationship between the magnitude of serum APP response with the severity of disease, providing an objective tool for validation the severity of infection. The maximum concentration of SAA in serum was closely correlated with lung score and makes this APP potential indicator for disease progress or estimation of treatment strategy.
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Pomorska-Mól
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Kwit
authors.forename: Zygmunt
authors.initials: Z
authors.lastname: Pejsak
authors.forename: Iwona
authors.initials: I
authors.lastname: Markowska-Daniel
mesh_terms: D000209:Acute-Phase Proteins / Q000032:analysis*; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D058345:Asymptomatic Infections; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D053122:Influenza A Virus, H3N2 Subtype / Q000276:immunology*; D008297:Male; D009976:Orthomyxoviridae Infections / Q000473:pathology / Q000662:veterinary*; D044967:Serum / Q000737:chemistry; D013552:Swine; D013553:Swine Diseases / Q000276:immunology* / Q000473:pathology / Q000821:virology*; D013997:Time Factors; D017201:Virus Shedding
chemical_list: D000209:Acute-Phase Proteins; D000914:Antibodies, Viral
references.citation: Clin Infect Dis. 2007 Apr 15;44(8):1084-8
references.pmid: 17366454
references.citation: Vet Res. 2011 May 18;42:66
references.pmid: 21592356
references.citation: Emerg Infect Dis. 2007 Dec;13(12):1871-8
references.pmid: 18258038
references.citation: J Clin Pathol. 1985 Mar;38(3):312-6
references.pmid: 3973057
references.citation: Vet Q. 2006 Jun;28(2):46-53
references.pmid: 16841566
references.citation: Vet Microbiol. 2000 May 22;74(1-2):29-46
references.pmid: 10799776
references.citation: Vet Immunol Immunopathol. 2006 Sep 15;113(1-2):157-68
references.pmid: 16774789
references.citation: Vet J. 2011 Jan;187(1):48-53
references.pmid: 20097110
references.citation: Comp Biochem Physiol B Biochem Mol Biol. 1998 Feb;119(2):365-73
references.pmid: 9629669
references.citation: PLoS One. 2010 Feb 05;5(2):e9068
references.pmid: 20140096
references.citation: Vet Microbiol. 2012 Oct 12;159(3-4):499-503
references.pmid: 22580193
references.citation: Vet Immunol Immunopathol. 2011 Jul 15;142(1-2):81-6
references.pmid: 21501880
references.citation: Influenza Other Respir Viruses. 2010 Sep;4(5):277-93
references.pmid: 20716157
references.citation: Vet Res. 2010 Sep-Oct;41(5):74
references.pmid: 20663475
references.citation: FEMS Immunol Med Microbiol. 2012 Dec;66(3):334-42
references.pmid: 22924885
references.citation: Vet J. 2004 Jul;168(1):28-40
references.pmid: 15158206
references.citation: J Gen Virol. 2005 Jul;86(Pt 7):1943-1951
references.pmid: 15958672
references.citation: Emerg Infect Dis. 2002 Aug;8(8):814-9
references.pmid: 12141967
references.citation: Vet Microbiol. 2009 Jul 2;138(1-2):53-61
references.pmid: 19356864
references.citation: Acta Vet Scand. 1999;40(4):323-33
references.pmid: 10918902
references.citation: Immunol Today. 1994 Feb;15(2):74-80
references.pmid: 7512342