Experimental infection of Atlantic halibut Hippoglossus Hippoglossus with nodavirus: tissue distribution and immune response

• Published in: Diseases of aquatic organisms Vol. 53; no. 3; pp. 211 - 221
• Main Authors: GROVE, S, JOHANSEN, R, DANNEVIG, B. H, REITAN, L. J, RANHEIM, T
• Format: Journal Article
• Language: English
• Published: Oldendorf Inter-Research 27.02.2003
• Subjects: Animal aquaculture; Animal productions; Animals; Antibodies, Viral - analysis; Biological and medical sciences; Brain - pathology; Brain - virology; Enzyme-Linked Immunosorbent Assay - veterinary; Fish Diseases - immunology; Fish Diseases - virology; Flounder; Fundamental and applied biological sciences. Psychology; Gills - virology; Heart - virology; Hippoglossus hippoglossus; Immunocompetence; Immunohistochemistry - veterinary; Injections, Intraperitoneal - veterinary; Intestines - virology; Kidney - virology; Liver - virology; Nodaviridae - immunology; Nodaviridae - isolation & purification; Nodaviridae - physiology; Nodavirus; Pisciculture; Retina - pathology; Retina - virology; Reverse Transcriptase Polymerase Chain Reaction - veterinary; RNA Virus Infections - immunology; RNA Virus Infections - veterinary; RNA Virus Infections - virology; Vertebrate aquaculture; Immunohistochemistry; VER; Hippoglossus hippoglossus; Immunity; Host virus relation; Marine environment; Pisces; Nodaviridae; VNN; Localization; Atlantic halibut; Reverse transcription polymerase chain reaction; Farming animal; Immune response; Host; Infection; Virus; Vertebrata; Experimental disease; Experimental infection; Viral disease; Antibodies RT-PCR; ELISA assay; Nodavirus; Aquaculture; ELISA
• DOI: 10.3354/dao053211
• ISSN: 0177-5103

Atlantic halibut Hippoglossus hippoglossus, age 8 mo and weighing 20 g, were challenged by either intraperitoneal injection (i.p.) or by bath exposure using nodavirus isolated from Atlantic halibut. Fish were sampled at intervals over a 41 d period, starting on Day 5 post-challenge. Although no clinical disease or mortality was recorded, the data show that nodavirus did successfully propagate in i.p.-challenged fish. Using conventional end-point reverse transcription (RT)-PCR, nodavirus was detected in the kidney of all examined i.p.-challenged fish, and further in the head, heart, liver and posterior intestine of most of these individuals. Quantitative real-time RT-PCR revealed that the amount of virus in head samples from the i.p.-challenged group increased during the experiment. The presence of nodavirus in nervous tissue of i.p.-challenged fish was detected by immunohistochemistry from Day 13 post-challenge. In the retina, virus positive cells were found adjacent to the circumferential germinal zone at the ciliary margin towards the iris. In the brain, a few positive cells were detected in the tectum opticum. An ELISA was developed to detect anti-nodavirus activity in plasma. The method included an optimized coating procedure, which allowed the use of non-purified nodavirus as the coating antigen in a simple indirect ELISA. An anti-nodavirus antibody response was detected from Day 19 post-challenge in i.p.-challenged fish, while a response was not detected in the bath-challenged or control fish. This experiment demonstrates a subclinical nodavirus infection in Atlantic halibut at a post-juvenile stage induced by i.p. injection of virus.