title: Prophylactic administration of chicken cathelicidin-2 boosts zebrafish embryonic innate immunity.
abstract: Chicken cathelicidin-2 (CATH-2) is a host defense peptide that exhibits immunomodulatory and antibacterial properties. Here we examined effects of CATH-2 in zebrafish embryos in the absence and presence of infection. Yolk-injection of 0.2-1.5 h post-fertilized (hpf) zebrafish embryos with 2.6 ng/kg CATH-2 increased proliferation of phagocytic cells at 48 hpf by 30%. A lethal infection model was developed to test the prophylactic protective effect of CATH-2 peptide. Embryos (0.2-1.5 hpf) were injected with 2.6 ng/kg CATH-2, challenged with a lethal dose of fluorescently labeled Salmonella enteritidis pGMDs3 at 28 hpf and monitored for survival. Prophylactic treatment with CATH-2 was found to delay infection starting at 22 h post-infection (hpi). At 18-20 hpi, significantly lower (2-fold) fluorescence intensity and decreased bacterial loads were detected in peptide-treated embryos. Thus prophylactic administration of low CATH-2 concentrations confer partial protection in zebrafish embryos by boosting the innate immune system.
authors.affiliation: Department of Infectious Diseases and Immunology, Division Molecular Host Defence, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.
authors.forename: Viktoria A F
authors.initials: VA
authors.lastname: Schneider
authors.affiliation: Department of Infectious Diseases and Immunology, Division Molecular Host Defence, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.
authors.forename: Albert
authors.initials: A
authors.lastname: van Dijk
authors.affiliation: Department of Medical Microbiology and Infection Control, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Astrid M
authors.initials: AM
authors.lastname: van der Sar
authors.affiliation: Department of Infectious Diseases and Immunology, Division Molecular Host Defence, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.
authors.forename: Marina D
authors.initials: MD
authors.lastname: Kraaij
authors.affiliation: Department of Infectious Diseases and Immunology, Division Molecular Host Defence, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.
authors.forename: Edwin J A
authors.initials: EJ
authors.lastname: Veldhuizen
authors.affiliation: Department of Infectious Diseases and Immunology, Division Molecular Host Defence, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands. Electronic address: h.p.haagsman@uu.nl.
authors.forename: Henk P
authors.initials: HP
authors.lastname: Haagsman
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage*; D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000008:administration & dosage*; D049109:Cell Proliferation; D004353:Drug Evaluation, Preclinical; D004625:Embryo, Nonmammalian / Q000187:drug effects / Q000276:immunology; D005393:Fish Diseases / Q000276:immunology* / Q000382:microbiology / Q000517:prevention & control; D007113:Immunity, Innate / Q000187:drug effects*; D010586:Phagocytes / Q000502:physiology; D012481:Salmonella Infections, Animal / Q000276:immunology* / Q000382:microbiology / Q000517:prevention & control; D012477:Salmonella enteritidis / Q000276:immunology; D015027:Zebrafish / Q000276:immunology*
chemical_list: D000276:Adjuvants, Immunologic; D023181:Antimicrobial Cationic Peptides; C504855:CMAP27 protein, chicken
keywords: Chicken cathelicidin-2; Host defense peptide; Immune stimulation; Salmonella enteritidis; Zebrafish embryos