Forkhead Box O1 Regulates Macrophage Polarization Following Staphylococcus aureus Infection: Experimental Murine Data and Review of the Literature

Yu Chen Wang, Hong Di Ma, Xue Ying Yin, Yin Hu Wang, Qing Zhi Liu, Jing Bo Yang, Qing Hua Shi, Baolin Sun, M. Eric Gershwin, Zhe Xiong Lian

Research output: Contribution to journalArticle

14 Scopus citations

Abstract

The functions of macrophages that lead to effective host responses are critical for protection against Staphylococcus aureus. Deep tissue-invading S. aureus initially countered by macrophages trigger macrophage accumulation and induce inflammatory responses through surface receptors, especially toll-like receptor 2 (TLR2). Here, we found that macrophages formed sporadic aggregates in the liver during infection. Within those aggregates, macrophages co-localized with T cells and were indispensable for their infiltration. In addition, we have focused on the mechanisms underlying the polarization of macrophages in Forkhead box transcription factor O1 (FoxO1) conditional knockout LysCre/+FoxO1fl/fl mice following S. aureus infection and report herein that macrophage M1-M2 polarization via TLR2 is intrinsically regulated by FoxO1. Indeed, for effective FoxO1 activity, stimulation of TLR2 is essential. However, following S. aureus challenge, there was a decrease in macrophage FoxO1, with increased phosphorylation of FoxO1 because of TLR2-mediated activation of PI3K/Akt and c-Raf/MEK/ERK pathway. Following infection in LysCre/+FoxO1fl/fl mice, mice became more susceptible to S. aureus with reduced macrophage aggregation in the liver and attenuated Th1 and Th17 responses. FoxO1 abrogation reduced M1 pro-inflammatory responses triggered by S. aureus and enhanced M2 polarization in macrophages. In contrast, overexpression of FoxO1 in macrophages increased pro-inflammatory mediators and functional surface molecule expression. In conclusion, macrophage FoxO1 is critical to promote M1 polarization and maintain a competent T cell immune response against S. aureus infection in the liver. FoxO1 regulates macrophage M1-M2 polarization downstream of TLR2 dynamically through phosphorylation.

Original languageEnglish (US)
Pages (from-to)1-17
Number of pages17
JournalClinical Reviews in Allergy and Immunology
DOIs
StateAccepted/In press - Feb 29 2016

Keywords

  • Liver infection
  • Macrophage polarization
  • Staphylococcus aureus
  • Toll-like receptor 2

ASJC Scopus subject areas

  • Immunology and Allergy

Fingerprint Dive into the research topics of 'Forkhead Box O1 Regulates Macrophage Polarization Following Staphylococcus aureus Infection: Experimental Murine Data and Review of the Literature'. Together they form a unique fingerprint.

  • Cite this