Vet. Res. 37 (2006) 75-87
DOI: 10.1051/vetres:2005043

Differential proteomic analysis reveals increased cathelicidin expression in porcine bronchoalveolar lavage fluid after an Actinobacillus pleuropneumoniae infection

Isabel Hennig-Pauka^{a, b}, Ilse Jacobsen^a, Frank Blecha^c, Karl-Heinz Waldmann^b and Gerald-Friedrich Gerlach<sup>a

a</sup>  Institute for Microbiology, Department of Infectious Diseases, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
^b  Clinic for Swine and Small Ruminants, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
^c  Department of Anatomy and Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, USA

(Received 23 December 2004; accepted 23 June 2005; published online 13 December 2005)

Abstract - Accurate definition of respiratory health in pigs is an important problem for swine producers and veterinarians. In an approach to identify potential biomarkers, two-dimensional gel electrophoresis and mass spectrometry on bronchoalveolar lavage fluid (BALF)-derived proteins from pigs experimentally infected with Actinobacillus pleuropneumoniae were performed at different time points post infection. Mock-infected pigs were used as a control. It was shown that the antimicrobial peptides, prophenin-2 and PR-39, and the calcium-binding protein calgranulin C were reproducibly upregulated in BALF of pigs chronically infected with A. pleuropneumoniae. Concentrations of PR-39 were significantly (p < 0.05) increased in BALF (median of 4.8 nM) but not in serum (median of 2.5 nM) on day 21 after infection. A Receiver Operating Characteristics (ROC) plot showed that PR-39 in BALF is an accurate and easily accessible marker to detect clinically healthy pigs convalescent from an experimental A. pleuropneumoniae infection. These results imply that PR-39 might have a potential as a general biomarker to determine porcine respiratory health.

Key words: antimicrobial peptide / PR-39 / BALF / porcine respiratory tract

Corresponding author: Gerald-Friedrich Gerlach gfgerlach@gmx.de

© INRA, EDP Sciences 2005