Respiratory immunity is an important component of protection elicited by subunit vaccination against pneumonic plague.
Mice were vaccinated with a recombinant fusion protein, rF1-V, by an intramuscular prime followed by an intranasal boost, to evaluate protection against pneumonic plague. Forty-two days after the intranasal boost, the mice were challenged by aerosol exposure to Yersinia pestis. Survival after exposure depended upon the dose of rF1-V given i.n. with > or = 80% survival in the highest dose groups. Pulmonary and serum antibody titers to V were the best predictors of outcome. For vaccinated mice that succumbed to the infection, death was delayed by 1-2 days compared to sham-inoculated controls. Weight loss early after exposure correlated with outcome. Pathology studies indicated a severe, necrotizing bronchopneumonia in vaccinated mice that succumbed to the infection, compatible with a prolonged disease course, while the lungs of sham-inoculated mice had only mild pneumonia, which is compatible with a more rapid disease course. Immunity in the respiratory tract appears to be critical for protection against primary pneumonia caused by Y. pestis.
Reed
Douglas S
DS
Center for Aerobiological Sciences, US Army Medical Research Institute of Infectious Diseases (USAMRIID), 1425 Porter Street, Fort Detrick, Frederick, MD 21702-5011, USA. doug.reed@det.amedd.army.mil
Martinez
Mark J
MJ
D000818:Animals; D000942:Antigens, Bacterial / Q000276:immunology*; D001426:Bacterial Proteins / Q000276:immunology*; D008168:Lung / Q000473:pathology; D051379:Mice; D010930:Plague / Q000473:pathology / Q000517:prevention & control*; D010931:Plague Vaccine / Q000276:immunology*; D052899:Pore Forming Cytotoxic Proteins; D014611:Vaccination; D022223:Vaccines, Subunit / Q000276:immunology; D014614:Vaccines, Synthetic / Q000276:immunology*; D015010:Yersinia pestis / Q000276:immunology
D000942:Antigens, Bacterial; D001426:Bacterial Proteins; C043908:LcrV protein, Yersinia; D010931:Plague Vaccine; D052899:Pore Forming Cytotoxic Proteins; D022223:Vaccines, Subunit; D014614:Vaccines, Synthetic; C086725:caf1 protein, Yersinia pestis