Evaluation of the Protective Efficacy of Different Doses of a Chlamydia abortus Subcellular Vaccine in a Pregnant Sheep Challenge Model for Ovine Enzootic Abortion

Chlamydia abortus causes the disease ovine enzootic abortion, which is one of the most infectious causes of foetal death in small ruminants worldwide. While the disease can be controlled using live and inactivated commercial vaccines, there is scope for improvements in safety for both sheep and huma...

ver descrição completa

Detalhes bibliográficos
Autores: Livingstone, Morag, Aitchison, Kevin, Palarea Albaladejo, Javier, Chianini, Francesca, Rocchi, Mara Silvia, Gastón Caspe, Sergio, Underwood, Clare, Flockhart, Allen, Wheelhouse, Nicholas, Entrican, Gary, Wattegedera, Sean Ranjan, Longbottom, David
Tipo de documento: artigo
Estado:Versão publicada
Data de publicação:2024
País:España
Recursos:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositório:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:10256/25505
Acesso em linha:http://hdl.handle.net/10256/25505
Access Level:Acceso aberto
Palavra-chave:Ovelles -- Vacunació
Sheep -- Vaccination
Ovelles -- Patògens
Sheep -- Pathogens
Bacteris patògens
Pathogenic bacteria
Descrição
Resumo:Chlamydia abortus causes the disease ovine enzootic abortion, which is one of the most infectious causes of foetal death in small ruminants worldwide. While the disease can be controlled using live and inactivated commercial vaccines, there is scope for improvements in safety for both sheep and human handlers of the vaccines. We have previously reported the development of a new prototype vaccine based on a detergent-extracted outer membrane protein preparation of C. abortus that was determined to be more efficacious and safer than the commercial vaccines when administered in two inoculations three weeks apart. In this new study, we have developed this vaccine further by comparing its efficacy when delivered in one or two (1 × 20 µg and 2 × 10 µg) doses, as well as also comparing the effect of reducing the antigen content of the vaccine by 50% (2 × 5 µg and 1 × 10 µg). All vaccine formulations performed well in comparison to the unvaccinated challenge control group, with no significant differences observed between vaccine groups, demonstrating that the vaccine can be administered as a single inoculation and at a lower dose without compromising efficacy. Future studies should focus on further defining the optimal antigen dose to increase the commercial viability of the vaccine