title: Post-exposure vaccination against Mycobacterium tuberculosis.
abstract: Enhancing immunity to tuberculosis in animal models after exposure to the infection has proved difficult. In this study we used a newly described flow cytometric technique to monitor changes in cell populations accumulating in the lungs of guinea pigs challenged by low-dose aerosol infection with Mycobacterium tuberculosis and vaccinated 10 days later. On day 40 after infection the fusion protein F36 and a pool of Ag85A and ESAT6 vaccines had significant effects on the bacterial load, showed increased expression of the activation marker CD45+ on CD4+ T cells, and reduced numbers of heterophils. Lung pathology and pathology scores were marginally improved in animals given these vaccines, but lymph node pathology was not influenced. Despite early effects no changes in long-term survival were seen. These results suggest that a single post-exposure vaccination can initially slow the disease process. However, this effect is transient, but this could be of use in an multidrug resistant/extremely drug resistant outbreak situation because it could potentially slow the infection long enough to complete drug susceptibility testing and initiate effective chemotherapy.
authors.affiliation: Colorado State University, Fort Collins, CO 80523-1682, USA.
authors.forename: Marcela
authors.initials: M
authors.lastname: Henao-Tamayo
authors.forename: Gopinath S
authors.initials: GS
authors.lastname: Palaniswamy
authors.forename: Erin E
authors.initials: EE
authors.lastname: Smith
authors.forename: Crystal A
authors.initials: CA
authors.lastname: Shanley
authors.forename: Baolin
authors.initials: B
authors.lastname: Wang
authors.forename: Ian M
authors.initials: IM
authors.lastname: Orme
authors.forename: Randall J
authors.initials: RJ
authors.lastname: Basaraba
authors.forename: Nancy M
authors.initials: NM
authors.lastname: DuTeau
authors.forename: Diane
authors.initials: D
authors.lastname: Ordway
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D004195:Disease Models, Animal; D018450:Disease Progression; D005260:Female; D005434:Flow Cytometry / Q000379:methods; D006168:Guinea Pigs; D017493:Leukocyte Common Antigens / Q000378:metabolism; D008168:Lung / Q000276:immunology / Q000382:microbiology; D009169:Mycobacterium tuberculosis / Q000276:immunology / Q000302:isolation & purification; D016176:T-Lymphocyte Subsets / Q000276:immunology; D032581:Tuberculosis Vaccines / Q000276:immunology*; D014397:Tuberculosis, Pulmonary / Q000276:immunology / Q000382:microbiology / Q000517:prevention & control*; D014400:Tuberculosis, Splenic / Q000276:immunology / Q000382:microbiology / Q000517:prevention & control; D014611:Vaccination / Q000379:methods
chemical_list: D032581:Tuberculosis Vaccines; D017493:Leukocyte Common Antigens