Analysis of DNA-vaccinated fish reveals viral antigen in muscle, kidney and thymus, and transient histopathologic changes.
A highly efficacious DNA vaccine against a fish rhabdovirus, infectious hematopoietic necrosis virus (IHNV), was used in a systematic study to analyze vaccine tissue distribution, persistence, expression patterns, and histopathologic effects. Vaccine plasmid pIHNw-G, containing the gene for the viral glycoprotein, was detected immediately after intramuscular injection in all tissues analyzed, including blood, but at later time points was found primarily in muscle tissue, where it persisted to 90 days. Glycoprotein expression was detected in muscle, kidney, and thymus tissues, with levels peaking at 14 days and becoming undetectable by 28 days. Histologic examination revealed no vaccine-specific pathologic changes at the standard effective dose of 0.1 mug DNA per fish, but at a high dose of 50 mug an increased inflammatory response was evident. Transient damage associated with needle injection was localized in muscle tissue, but by 90 days after vaccination no damage was detected in any tissue, indicating the vaccine to be safe and well tolerated.
Garver
Kyle A
KA
Department of Pathobiology, University of Washington, Seattle, WA 98195, USA. kagarver@u.washington.edu
Conway
Carla M
CM
Elliott
Diane G
DG
Kurath
Gael
G
D000818:Animals; D000956:Antigens, Viral / Q000032:analysis* / Q000276:immunology; D005393:Fish Diseases / Q000517:prevention & control; D006023:Glycoproteins / Q000096:biosynthesis; D007150:Immunohistochemistry / Q000379:methods; D029142:Infectious hematopoietic necrosis virus / Q000235:genetics / Q000276:immunology*; D007273:Injections, Intramuscular / Q000662:veterinary; D007668:Kidney / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D009132:Muscles / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D017686:Oncorhynchus mykiss / Q000276:immunology* / Q000378:metabolism / Q000502:physiology; D010957:Plasmids / Q000235:genetics; D016133:Polymerase Chain Reaction; D018353:Rhabdoviridae Infections / Q000517:prevention & control / Q000662:veterinary; D012680:Sensitivity and Specificity; D013950:Thymus Gland / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D013997:Time Factors; D014018:Tissue Distribution; D019444:Vaccines, DNA / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics*; D014765:Viral Vaccines / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics*
D000956:Antigens, Viral; D006023:Glycoproteins; D019444:Vaccines, DNA; D014765:Viral Vaccines