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The dose-dependent effect on protection and humoral response to a DNA vaccine against Infectious Hematopoietic Necrosis (IHN) virus in subyearling rainbow trout

Scott E. LaPatra·Serge Corbeil·Gerald R. Jones·William D. Shewmaker·Gael Kurath
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Abstract

A dose&ndash;response study that used the DNA vaccine pIHNw-G against infectious hematopoietic necrosis virus (IHNV) showed that complete and highly significant ( P < 0.001) protection against a virus injection challenge can be attained in subyearling rainbow trout Oncorhynchus mykiss (145&ndash;160 g, 8- to 10-months-old) 6 weeks after a single intramuscular injection with doses as low as 1 &mu;g. Complete protection was also reproducibly demonstrated at higher vaccine doses; however, no protection was observed with a 0.1-&mu;g dose. Virus-neutralizing antibody titers were detected in fish that had been vaccinated with different doses of the DNA vaccine and then sham-infected; there appeared to be a dose-dependent effect, with higher titers obtained with higher doses of vaccine. The DNA-vaccinated animals that survived virus challenge had significantly ( P < 0.05) higher neutralizing antibody titers than sham-infected, DNA-vaccinated control fish. Additionally, the titers detected in the IHN survivors exhibited a significant ( P < 0.05) dose-dependent effect, with the highest titers being present in fish that received the highest vaccine doses.

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Scott E. LaPatra, Serge Corbeil, Gerald R. Jones, William D. Shewmaker, Gael Kurath. 2000. The dose-dependent effect on protection and humoral response to a DNA vaccine against Infectious Hematopoietic Necrosis (IHN) virus in subyearling rainbow trout. https://doi.org/10.1577/1548-8667(2000)012%3C0181%3Afddeop%3E2.0.co%3B2

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