AUTHOR=Jones Jonathan W., Broz Petr , Monack Denise M.

TITLE=Innate Immune Recognition of Francisella Tularensis: Activation of Type-I Interferons and the Inflammasome

JOURNAL=Frontiers in Microbiology

VOLUME=2

YEAR=2011

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2011.00016

DOI=10.3389/fmicb.2011.00016

ISSN=1664-302X

ABSTRACT=<p>Francisella tularensis is an intracellular pathogen that can cause severe disease in a wide range of mammalian hosts. Primarily residing in host macrophages, <italic>F. tularensis</italic> escapes phagosomal degradation, and replicates in the macrophage cytosol. The macrophage uses a series of pattern recognition receptors to detect conserved microbial molecules from invading pathogens, and initiates an appropriate host response. In the cytosol, <italic>F. tularensis</italic> is recognized by the inflammasome, a multiprotein complex responsible for the activation of the cysteine protease caspase-1. Caspase-1 activation leads to processing and release of proinflammatory cytokines and host cell death. Here we review recent work on the molecular mechanisms of inflammasome activation by <italic>F. tularensis</italic>, and its consequences both <italic>in vitro</italic> and <italic>in vivo</italic>. Finally, we discuss the coordination between the inflammasome and other cytosolic host responses, and the evidence for <italic>F. tularensis</italic> virulence factors that suppress inflammasome activation.</p>