DNA vaccines encoding proteins from wild-type and attenuated canine distemper virus protect equally well against wild-type virus challenge.
Immunity induced by DNA vaccines containing the hemagglutinin (H) and nucleoprotein (N) genes of wild-type and attenuated canine distemper virus (CDV) was investigated in mink (Mustela vison), a highly susceptible natural host of CDV. All DNA-immunized mink seroconverted, and significant levels of virus-neutralizing (VN) antibodies were present on the day of challenge with wild-type CDV. The DNA vaccines also primed the cell-mediated memory responses, as indicated by an early increase in the number of interferon-gamma (IFN-γ)-producing lymphocytes after challenge. Importantly, the wild-type and attenuated CDV DNA vaccines had a long-term protective effect against wild-type CDV challenge. The vaccine-induced immunity induced by the H and N genes from wild-type CDV and those from attenuated CDV was comparable. Because these two DNA vaccines were shown to protect equally well against wild-type virus challenge, it is suggested that the genetic/antigenic heterogeneity between vaccine strains and contemporary wild-type strains are unlikely to cause vaccine failure.
Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen, Stigbøjlen 7, 1870 Frederiksberg C, Copenhagen, Denmark. Lin@life.ku.dk
Line
L
Nielsen
Trine Hammer
TH
Jensen
Birte
B
Kristensen
Tove Dannemann
TD
Jensen
Peter
P
Karlskov-Mortensen
Morten
M
Lund
Bent
B
Aasted
Merete
M
Blixenkrone-Møller
D000818:Animals; D057134:Antibodies, Neutralizing / Q000097:blood / Q000276:immunology; D000914:Antibodies, Viral / Q000097:blood / Q000276:immunology; D004216:Distemper / Q000276:immunology / Q000517:prevention & control*; D004217:Distemper Virus, Canine / Q000235:genetics / Q000276:immunology*; D005260:Female; D006389:Hemagglutinins, Viral / Q000235:genetics / Q000276:immunology*; D007114:Immunization; D008907:Mink / Q000276:immunology; D009698:Nucleoproteins / Q000235:genetics / Q000276:immunology*; D014613:Vaccines, Attenuated / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology; D019444:Vaccines, DNA / Q000008:administration & dosage* / Q000235:genetics / Q000276:immunology; D014765:Viral Vaccines / Q000008:administration & dosage* / Q000235:genetics / Q000276:immunology
D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D006389:Hemagglutinins, Viral; D009698:Nucleoproteins; D014613:Vaccines, Attenuated; D019444:Vaccines, DNA; D014765:Viral Vaccines