title: Skin mucus of Cyprinus carpio inhibits cyprinid herpesvirus 3 binding to epidermal cells.
abstract: Cyprinid herpesvirus 3 (CyHV-3) is the aetiological agent of a mortal and highly contagious disease in common and koi carp. The skin is the major portal of entry of CyHV-3 in carp after immersion in water containing the virus. In the present study, we used in vivo bioluminescence imaging to investigate the effect of skin mucus removal and skin epidermis lesion on CyHV-3 entry. Physical treatments inducing removal of the mucus up to complete erosion of the epidermis were applied on a defined area of carp skin just before inoculation by immersion in infectious water. CyHV-3 entry in carp was drastically enhanced on the area of the skin where the mucus was removed with or without associated epidermal lesion. To investigate whether skin mucus inhibits CyHV-3 binding to epidermal cells, tail fins with an intact mucus layer or without mucus were inoculated ex vivo. While electron microscopy examination revealed numerous viral particles bound on the fins inoculated after mucus removal, no particle could be detected after infection of mucus-covered fins. Finally, anti-CyHV-3 neutralising activity of mucus extract was tested in vitro. Incubation of CyHV-3 with mucus extract reduced its infectivity in a dose dependent manner. The present study demonstrates that skin mucus removal and epidermal lesions enhance CyHV-3 entry in carp. It highlights the role of fish skin mucus as an innate immune protection against viral epidermal entry.
authors.affiliation: Immunology-Vaccinology (B43b), Department of Infectious and Parasitic Diseases (B43b), Faculty of Veterinary Medicine, University of Liège, 4000 Liège, Belgium. a.vdplasschen@ulg.ac.be.
authors.forename: Victor Stalin
authors.initials: VS
authors.lastname: Raj
authors.forename: Guillaume
authors.initials: G
authors.lastname: Fournier
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Rakus
authors.forename: Maygane
authors.initials: M
authors.lastname: Ronsmans
authors.forename: Ping
authors.initials: P
authors.lastname: Ouyang
authors.forename: Benjamin
authors.initials: B
authors.lastname: Michel
authors.forename: Cédric
authors.initials: C
authors.lastname: Delforges
authors.forename: Bérénice
authors.initials: B
authors.lastname: Costes
authors.forename: Frédéric
authors.initials: F
authors.lastname: Farnir
authors.forename: Baptiste
authors.initials: B
authors.lastname: Leroy
authors.forename: Ruddy
authors.initials: R
authors.lastname: Wattiez
authors.forename: Charles
authors.initials: C
authors.lastname: Melard
authors.forename: Jan
authors.initials: J
authors.lastname: Mast
authors.forename: François
authors.initials: F
authors.lastname: Lieffrig
authors.forename: Alain
authors.initials: A
authors.lastname: Vanderplasschen
mesh_terms: D000818:Animals; D002347:Carps; D002478:Cells, Cultured; D004266:DNA Virus Infections / Q000276:immunology / Q000662:veterinary* / Q000821:virology; D004267:DNA Viruses / Q000276:immunology*; D004817:Epidermis / Q000276:immunology / Q000821:virology; D005393:Fish Diseases / Q000276:immunology* / Q000821:virology; D007113:Immunity, Innate; D008163:Luminescent Measurements / Q000662:veterinary; D046529:Microscopy, Electron, Transmission / Q000662:veterinary; D009093:Mucus / Q000276:immunology* / Q000821:virology; D053585:Virus Attachment