Frequency of IFN-γ producing cells correlates with adjuvant enhancement of bacille Calmette-Guèrin induced protection against Mycobacterium bovis

• Published in: Vaccine 2005-12, Vol.23 (48), p.5526-5532
• Main Authors: Logan, Karen E., Chambers, Mark A., Hewinson, R. Glyn, Hogarth, Philip J.
• Format: Article
• Language: English
• Subjects: Adjuvants, Immunologic - pharmacology; Animals; Antibodies, Bacterial - biosynthesis; Antigens, Bacterial - immunology; Applied microbiology; Bacterial diseases; BCG Vaccine - administration & dosage; BCG Vaccine - genetics; BCG Vaccine - immunology; Biological and medical sciences; Fundamental and applied biological sciences. Psychology; Human bacterial diseases; Infectious diseases; Interferon-gamma - biosynthesis; Medical sciences; Mice; Mice, Inbred BALB C; Microbiology; Mycobacterium bovis; Mycobacterium bovis - drug effects; Mycobacterium bovis - immunology; Prime-boost; Statistics as Topic; Tuberculosis; Tuberculosis and atypical mycobacterial infections; Vaccine; Vaccines, antisera, therapeutical immunoglobulins and monoclonal antibodies (general aspects); Vaccines, DNA - administration & dosage; Vaccines, DNA - immunology
• ISSN: 0264-410X; 1873-2518
• DOI: 10.1016/j.vaccine.2005.07.037

Tuberculosis caused by infection with Mycobacterium tuberculosis or Mycobacterium bovis remains one of the most important infectious diseases of man and animals. The current vaccine M. bovis Calmette-Guérin (BCG) demonstrates variable efficacy and so a more robust strategy to either replace, or more likely supplement it, is required. Prime-boost strategies where immunity induced by BCG is boosted by a second heterologous vaccine represent a promising avenue of research. We have evaluated the ability of a protein subunit vaccine using the antigen Rv3019c to either prime or boost immunity induced by BCG in a murine M. bovis challenge model. Despite the induction of anamnestic T cell responses, we report that antigen-independent immune stimulation with adjuvant in conjunction with BCG could enhance the level of protection induced by BCG alone. Importantly this improved protection correlated with pre-infection frequencies of ex vivo IFN-γ producing cells in the spleen, providing a possible surrogate correlate of protection for future vaccination studies.