Immunogenicity of recombinant VP2 proteins of all nive serotypes of African horse sickness virus
Kanai, Y. ; Rijn, P.A. van; Maris-Veldhuis, M.A. ; Kaname, Y. ; Athmaram, T.N. ; Roy, P. - \ 2014
Vaccine 32 (2014)39. - ISSN 0264-410X - p. 4932 - 4937.
outer capsid proteins - horsesickness-virus - bluetongue virus - protective efficacy - vaccine - baculovirus - expression - challenge - responses - sheep
African horse sickness (AHS) is an equine disease with a mortality of up to 90% for susceptible horses. The causative agent AHS virus (AHSV) is transmitted by species of Culicoides. AHSV serogroup within the genus Orbivirus of the Reoviridae family consists of nine serotypes that show no or very limited cross-neutralization. Of the seven structural proteins (VP1-VP7) of AHSV, VP2 is the serotype specific protein, and the major target for neutralizing antibodies. In this report, recombinant VP2 proteins of all nine serotypes were expressed individually by the baculovirus expression system and the immunogenicity of each was studied by immunization of guinea pigs with single VP2 as well as with cocktails of VP2 proteins. Homologous neutralizing antibodies measured by 50% plaque reduction assay showed varying degrees (from 37 to 1365) of titers for different VP2 proteins. A low cross-neutralizing antibody titer was found for genetically related AHSV serotypes. Immunization with VP2 cocktails containing equal amounts of each of the VP2 proteins also triggered neutralizing antibodies albeit to lower titers (4-117) to each of the serotypes in the cocktail. This study is a first step to develop a VP2 subunit vaccine for AHS and our results indicate that VP2 subunit vaccines are feasible individually or in a multi-serotype cocktail.
Immunological and molecular characterization of susceptibility in relationship to bacterial strain differences in Mycobacterium avium subsp paratuberculosis infection in the red deer (Cervus elaphus)
O'Brien, R. ; Mackintosh, C.G. ; Bakker, D. ; Kopecna, M. ; Pavlik, I. ; Griffin, J.F.T. - \ 2006
Infection and Immunity 74 (2006)6. - ISSN 0019-9567 - p. 3530 - 3537.
fragment-length-polymorphism - johnes-disease - protective efficacy - immune-responses - new-zealand - wild ruminants - farmed deer - tuberculosis - sheep - is900
Johne's disease (JD) infection, caused by Mycobacterium avium subsp. paratuberculosis, represents a major disease problem in farmed ruminants. Although JD has been well characterized in cattle and sheep, little is known of the infection dynamics or immunological response in deer. In this study, typing of M. avium subsp. paratuberculosis isolates from intestinal lymphatic tissues from 74 JD-infected animals showed that clinical isolates of M. avium subsp. paratuberculosis from New Zealand farmed red deer were exclusively of the bovine strain genotype. The susceptibility of deer to M. avium subsp. paratuberculosis was further investigated by experimental oral-route infection studies using defined isolates of virulent bovine and ovine M. avium subsp. paratuberculosis strains. Oral inoculation with high (109 CFU/animal) or medium (107 CFU/animal) doses of the bovine strain of M. avium subsp. paratuberculosis established 100% infection rates, compared to 69% infection following inoculation with a medium dose of the ovine strain. The high susceptibility of deer to the bovine strain of M. avium subsp. paratuberculosis was confirmed by a 50% infection rate following experimental inoculation with a low dose of bacteria (103 CFU/animal). This study is the first to report experimental M. avium subsp. paratuberculosis infection in red deer, and it outlines the strong infectivity of bovine-strain M. avium subsp. paratuberculosis isolates for cervines.