The NLRP12 Inflammasome Recognizes Yersinia pestis

Division of Infectious Diseases and Immunology, UMass Medical School, Worcester, MA 01605, USA.
Immunity (Impact Factor: 19.75). 07/2012; 37(1):96-107. DOI: 10.1016/j.immuni.2012.07.006
Source: PubMed

ABSTRACT Yersinia pestis, the causative agent of plague, is able to suppress production of inflammatory cytokines IL-18 and IL-1β, which are generated through caspase-1-activating nucleotide-binding domain and leucine-rich repeat (NLR)-containing inflammasomes. Here, we sought to elucidate the role of NLRs and IL-18 during plague. Lack of IL-18 signaling led to increased susceptibility to Y. pestis, producing tetra-acylated lipid A, and an attenuated strain producing a Y. pseudotuberculosis-like hexa-acylated lipid A. We found that the NLRP12 inflammasome was an important regulator controlling IL-18 and IL-1β production after Y. pestis infection, and NLRP12-deficient mice were more susceptible to bacterial challenge. NLRP12 also directed interferon-γ production via induction of IL-18, but had minimal effect on signaling to the transcription factor NF-κB. These studies reveal a role for NLRP12 in host resistance against pathogens. Minimizing NLRP12 inflammasome activation may have been a central factor in evolution of the high virulence of Y. pestis.

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