title: Characterization of NLRP12 during the in vivo host immune response to Klebsiella pneumoniae and Mycobacterium tuberculosis.
abstract: The majority of nucleotide binding domain leucine rich repeats-containing (NLR) family members has yet to be functionally characterized. Of the described NLRs, most are considered to be proinflammatory and facilitate IL-1β production. However, a newly defined sub-group of NLRs that function as negative regulators of inflammation have been identified based on their abilities to attenuate NF-κB signaling. NLRP12 (Monarch-1) is a prototypical member of this sub-group that negatively regulates both canonical and noncanonical NF-κB signaling in biochemical assays and in colitis and colon cancer models. The role of NLRP12 in infectious diseases has not been extensively studied. Here, we characterized the innate immune response of Nlrp12(-/-) mice following airway exposure to LPS, Klebsiella pneumoniae and Mycobacterium tuberculosis. In response to E. coli LPS, Nlrp12(-/-) mice showed a slight decrease in IL-1β and increase in IL-6 production, but these levels were not statistically significant. During K. pneumoniae infection, we observed subtle differences in cytokine levels and significantly reduced numbers of monocytes and lymphocytes in Nlrp12(-/-) mice. However, the physiological relevance of these findings is unclear as no overt differences in the development of lung disease were observed in the Nlrp12(-/-) mice. Likewise, Nlrp12(-/-) mice demonstrated pathologies similar to those observed in the wild type mice following M. tuberculosis infection. Together, these data suggest that NLRP12 does not significantly contribute to the in vivo host innate immune response to LPS stimulation, Klebsiella pneumonia infection or Mycobacterium tuberculosis.
authors.affiliation: Lineberger Comprehensive Cancer Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC, USA. icallen@vt.edu
authors.forename: Irving C
authors.initials: IC
authors.lastname: Allen
authors.forename: Erin
authors.initials: E
authors.lastname: McElvania-TeKippe
authors.forename: Justin E
authors.initials: JE
authors.lastname: Wilson
authors.forename: John D
authors.initials: JD
authors.lastname: Lich
authors.forename: Janelle C
authors.initials: JC
authors.lastname: Arthur
authors.forename: Jonathan T
authors.initials: JT
authors.lastname: Sullivan
authors.forename: Miriam
authors.initials: M
authors.lastname: Braunstein
authors.forename: Jenny P Y
authors.initials: JP
authors.lastname: Ting
mesh_terms: D000818:Animals; D001854:Bone Marrow Cells / Q000166:cytology; D003713:Dendritic Cells / Q000166:cytology / Q000378:metabolism; D007113:Immunity, Innate; D015850:Interleukin-6 / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins / Q000172:deficiency / Q000378:metabolism*; D007710:Klebsiella Infections / Q000276:immunology / Q000378:metabolism; D007711:Klebsiella pneumoniae / Q000502:physiology*; D008168:Lung / Q000276:immunology / Q000382:microbiology; D051379:Mice; D009169:Mycobacterium tuberculosis / Q000502:physiology*; D014397:Tuberculosis, Pulmonary / Q000276:immunology / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D015850:Interleukin-6; D047908:Intracellular Signaling Peptides and Proteins; C553199:NLRP12 protein, mouse; D014409:Tumor Necrosis Factor-alpha