Novel vaccination strategies based on recombinant Mycobacterium bovis BCG

LKC Switzerland Ltd., Basel-Landschaft, Switzerland
International Journal of Medical Microbiology (Impact Factor: 3.61). 03/2003; 292(7-8):441-51. DOI: 10.1078/1438-4221-00227
Source: PubMed


In this manuscript, we will review the utilization of Mycobacterium bovis Bacille Calmette-Guerin (BCG) as a vaccine against tuberculosis (TB) and as a carrier system for heterologous antigens. BCG is one of the most widely used vaccines. Novel techniques in genome manipulation allow the construction of virulence-attenuated recombinant (r)-BCG strains that can be employed as homologous vaccines, or as heterologous antigen delivery systems, for priming pathogen-specific immunity against infectious diseases, including TB. Several approaches are available for heterologous antigen expression and compartmentalization in BCG and recent findings show the potential to modulate and direct the immune responses induced by r-BCG strains as desired. Recent achievements in complete genome analysis of various target pathogens, combined with a better understanding of protective pathogen-specific immune responses, form the basis for the rational design of a new generation of recombinant mycobacterial vaccines against a multitude of infectious diseases.

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Available from: Juergen Hess
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    • "Various clinical trials have demonstrated that BCG showed variable levels of efficacy against pulmonary TB. For example, a major trial in the United Kingdom showed >75% protection [3]; however, trials in south India and Malawi demonstrated that BCG failed to protect consistently against pulmonary TB [4,5]. The reasons for this have been a matter of debate and this indicates an urgent need for more effective vaccines to decrease the incidence of tuberculosis. "
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    • "Recently, Wang et al. [48] tested the efficacy of recombinant Mycobacterium bovis BCG expressing ROP2 gene as a vaccine, using mouse experimental toxoplasmosis model. BCG, widely applied in immunoprophylaxis of tuberculosis, is a particularly attractive vector for delivering heterologous antigens because mycobacteria elicit TH1-mediated immune response without an additional adjuvant [49]. Vaccine ROP2-BCG induced strong specific humoral and cellular (IL-2 and IFN-γ in supernatants of splenocytes cell cultures) immunity. "
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