Chicken antimicrobial peptides: biological functions and possible applications Albert van Dijk Chicken antimicrobial peptides: biological functions and possible applications Antimicrobiële peptiden van de kip: biologische functies en mogelijke toepassingen (met een samenvatting in het Nederlands) Proefschrift ter verkrijging van de graad van doctor aan de Universiteit Utrecht op gezag van de rector magnificus, prof. dr. J.C. Stoof, ingevolge het besluit van het college voor promoties in het openbaar te verdedigen op donderdag 15 november 2007 des middags te 4.15 uur door Albert van Dijk geboren op 23 maart 1965 te Heerjansdam Promotor: Prof. dr. H. P. Haagsman Co-promotor: Dr. E. J. A. Veldhuizen The work in this thesis was supported by a research grant (Adaptation and Resistance Program) from the Animal Science Group (Wageningen University and Research Center) and the Faculty of Veterinary Medicine (Utrecht University), The Netherlands. Chicken antimicrobial peptides: biological functions and possible applications /Albert van Dijk Department of Infectious Diseases and Immunology Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands ISBN: 978-90-393-4667-9 Cover design: Albert van Dijk & Marije Brouwer Lay-out: Harry Otter Printing: Gildeprint Drukkerijen Enschede Contents Chapter 1 Introduction 1 Chapter 2 The role of antimicrobial peptides in birds 9 Chapter 3 The β-defensin gallinacin-6 is expressed in the chicken digestive tract and has antimicrobial activity against food-borne pathogens 65 Chapter 4 CMAP27, a novel chicken cathelicidin-like antimicrobial Peptide 93 Chapter 5 Localization and function of the chicken cathelicidin CMAP27 in peripheral blood cells and digestive tract tissues 105 Chapter 6 CMAP27 in chicken uropygial gland secretion and skin injury – Putative role in growth inhibition of feather-degrading microorganisms and wound-repair 129 Chapter 7 General discussion 155 List of publications 171 Samenvatting 173 Dankwoord 177 Curriculum vitae 180 Chapter 1 Introduction Chapter 1 2