Open AccessEarly protection events in swine immunized with an experimental live attenuated classical swine fever marker vaccine, FlagT4G
Author(s) -
Lauren G. Holinka,
Vivian O’Donnell,
Guillermo R. Risatti,
Paul A. Azzinaro,
Jonathan Arzt,
Carolina Stenfeldt,
Lauro Velázquez-Salinas,
Jolene Carlson,
Douglas P. Gladue
Publication year - 2017
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0177433
Subject(s) - vaccination , attenuated vaccine , nasal administration , virology , immunity , outbreak , medicine , inoculation , immunology , classical swine fever , anthrax vaccines , immune system , inactivated vaccine , virus , biology , virulence , immunization , dna vaccination , biochemistry , gene
Prophylactic vaccination using live attenuated classical swine fever (CSF) vaccines has been a very effective method to control the disease in endemic regions and during outbreaks in previously disease-free areas. These vaccines confer effective protection against the disease at early times post-vaccination although the mechanisms mediating the protection are poorly characterized. Here we present the events occurring after the administration of our in-house developed live attenuated marker vaccine, FlagT4Gv. We previously reported that FlagT4Gv intramuscular (IM) administered conferred effective protection against intranasal challenge with virulent CSFV (BICv) as early as 7 days post-vaccination. Here we report that FlagT4Gv is able to induce protection against disease as early as three days post-vaccination. Immunohistochemical testing of tissues from FlagT4Gv-inoculated animals showed that tonsils were colonized by the vaccine virus by day 3 post-inoculation. There was a complete absence of BICv in tonsils of FlagT4Gv-inoculated animals which had been intranasal (IN) challenged with BICv 3 days after FlagT4Gv infection, confirming that FlagT4Gv inoculation confers sterile immunity. Analysis of systemic levels of 19 different cytokines in vaccinated animals demonstrated an increase of IFN-α three days after FlagT4Gv inoculation compared with mock infected controls.