Clin Exp Vaccine Res.  2014 Jul;3(2):155-167. 10.7774/cevr.2014.3.2.155.

Host immune responses to mycobacterial antigens and their implications for the development of a vaccine to control tuberculosis

• Yuk JM
• Jo EK

• KMID: 1730620
• DOI: http://doi.org/10.7774/cevr.2014.3.2.155

Abstract

Tuberculosis (TB) remains a worldwide health problem, causing around 2 million deaths per year. Despite the bacillus Calmette Guerin vaccine being available for more than 80 years, it has limited effectiveness in preventing TB, with inconsistent results in trials. This highlights the urgent need to develop an improved TB vaccine, based on a better understanding of host-pathogen interactions and immune responses during mycobacterial infection. Recent studies have revealed a potential role for autophagy, an intracellular homeostatic process, in vaccine development against TB, through enhanced immune activation. This review attempts to understand the host innate immune responses induced by a variety of protein antigens from Mycobacterium tuberculosis, and to identify future vaccine candidates against TB. We focus on recent advances in vaccine development strategies, through identification of new TB antigens using a variety of innovative tools. A new understanding of the host-pathogen relationship, and the usefulness of mycobacterial antigens as novel vaccine candidates, will contribute to the design of the next generation of vaccines, and to improving the host protective immune responses while limiting immunopathology during M. tuberculosis infection.

Keyword

Tuberculosis; BCG vaccine; Host-pathogen interactions; Innate immunity; Aadaptive immunity

MeSH Terms

Autophagy
BCG Vaccine
Host-Pathogen Interactions
Immunity, Innate
Mycobacterium tuberculosis
Tuberculosis*
Vaccines
BCG Vaccine
Vaccines

Figure

• 

  Fig. 1 A schematic diagram of host immune system against infection of Mycobacterium tuberculosis (Mtb). Mtb is inhaled by aerosols and transmitted to the lungs, where it is phagocytized by alveolar macrophages and eliminated via various mechanisms including apoptosis and autophagy. If the bacteria growth is arrested, but not eradicated, in early stage of infection, then the disease is preserved in latent condition without symptoms of tuberculosis (TB) in 90-95% of individuals. The phase is successfully finished with appropriate induction of host innate immune responses. Otherwise, in 5-10% of cases, Mtb is replicated into macrophages and disseminated to other tissue and organ, where TB develops with typical clinical symptoms including weight loss, pain in the chest, frequent coughing, and fibrosis of lung.

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