This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Jørgensen, J. B. Articles by Johansen, A. Search for Related Content PubMed PubMed Citation Articles by Jørgensen, J. B. Articles by Johansen, A.

 Previous Article  |  Next Article 

Journal of Virology, November 2003, p. 11471-11479, Vol. 77, No. 21
0022-538X/03/$08.00+0     DOI: 10.1128/JVI.77.21.11471-11479.2003
Copyright © 2003, American Society for Microbiology. All Rights Reserved.

CpG DNA Induces Protective Antiviral Immune Responses in Atlantic Salmon (Salmo salar L.)

Fiskeriforskning, Norwegian Institute of Fisheries and Aquaculture, N-9291 Tromsø, Norway

Received 13 March 2003/ Accepted 28 July 2003

Oligodeoxynucleotides (ODN) containing unmethylated CpG dinucleotides within specific sequence contexts (CpG motifs) are detected, like bacterial or viral DNA, as a danger signal by the vertebrate immune system. CpG ODN show promise as vaccine adjuvants and immunoprotective agents in animal models. Here we report that pretreatment with CpG ODN in animals induces nonspecific protection against viral infection. A panel of different synthetic CpG ODN was tested for the in vitro effects in Atlantic salmon (Salmo salar L.) leukocytes. The ODN were tested for their capacity to stimulate proliferation of peripheral blood leukocytes and to induce production of interferon-like factors in head kidney leukocytes. These studies revealed that the sequence and number of the CpG motifs as well as the lengths of the ODN contribute to their stimulatory activity. ODN with the 6-mer CpG motif (5'-GTCGTT-3') showed the highest stimulatory activity and were shown to induce protection against infectious pancreatic necrosis virus when injected in Atlantic salmon. Expression of the Mx transcript, as an indicator of alpha/beta interferon induction, was induced in the CpG-injected fish. These results suggest that CpG DNA in fish induces early, nonspecific antiviral protection.