Display Settings:

Format

Send to:

Choose Destination
We are sorry, but NCBI web applications do not support your browser and may not function properly. More information
    Infect Immun. 2012 Dec;80(12):4099-105. doi: 10.1128/IAI.00589-12. Epub 2012 Sep 10.

    Inflammatory monocyte recruitment is regulated by interleukin-23 during systemic bacterial infection.

    Source

    Department of Molecular Biology and Immunology, University of North Texas Health Science Center, Fort Worth, Texas, USA.

    Abstract

    Listeria monocytogenes is a gram-positive intracellular pathogen that causes meningitis and septicemia in immunocompromised individuals and spontaneous abortion in pregnant women. The innate immune response against L. monocytogenes is primarily mediated by neutrophils and monocytes. Interleukin-23 (IL-23) is an important proinflammatory cytokine well known for its role in neutrophil recruitment in various infectious and autoimmune diseases. We have previously shown that IL-23 is required for host resistance against L. monocytogenes and for neutrophil recruitment to the liver, but not the spleen, during infection. Despite efficient neutrophil recruitment to the spleen, IL-23p19 knockout (KO) mice have an increased bacterial burden in this organ, suggesting that IL-23 may regulate the recruitment/function of another cell type to the spleen. In this study, we show that specific depletion of neutrophils abrogated the differences in bacterial burdens in the livers but not the spleens of C57BL/6 (B6) and IL-23p19 KO mice. Interestingly, L. monocytogenes-infected IL-23p19 KO mice had fewer monocytes in the spleen than B6 mice, as well as a reduction in the monocyte-recruiting chemokines CCL2 and CCL7. Additionally, the overall concentrations of tumor necrosis factor alpha (TNF-α) and nitric oxide (NO(•)), as well as the percentages and total numbers of monocytes producing TNF-α and NO(•), were reduced in IL-23p19 KO mice compared to levels in B6 mice, leading to increased bacterial burdens in the spleens of L. monocytogenes-infected IL-23p19 KO mice. Collectively, our data establish that IL-23 is required for the optimal recruitment of TNF-α- and NO(•)-producing inflammatory monocytes, thus revealing a novel mechanism by which this proinflammatory cytokine provides protection against bacterial infection.

    PMID:
    22966045
    [PubMed - indexed for MEDLINE]
    PMCID:
    PMC3497429
    [Available on 2013/6/1]

      Supplemental Content

      Icon for HighWire

      Save items

      Recent activity

      Your browsing activity is empty.

      Activity recording is turned off.

      Turn recording back on

      See more...
      Write to the Help Desk