Frontiers in Immunology (May 2024)

Macrophage polarization in rheumatoid arthritis: signaling pathways, metabolic reprogramming, and crosstalk with synovial fibroblasts

  • Yixin Zheng,
  • Yixin Zheng,
  • Yixin Zheng,
  • Kai Wei,
  • Kai Wei,
  • Kai Wei,
  • Ping Jiang,
  • Ping Jiang,
  • Ping Jiang,
  • Jianan Zhao,
  • Jianan Zhao,
  • Jianan Zhao,
  • Yu Shan,
  • Yu Shan,
  • Yu Shan,
  • Yiming Shi,
  • Yiming Shi,
  • Yiming Shi,
  • Fuyu Zhao,
  • Fuyu Zhao,
  • Fuyu Zhao,
  • Cen Chang,
  • Cen Chang,
  • Cen Chang,
  • Yunshen Li,
  • Yunshen Li,
  • Yunshen Li,
  • Mi Zhou,
  • Mi Zhou,
  • Xinliang Lv,
  • Shicheng Guo,
  • Dongyi He,
  • Dongyi He,
  • Dongyi He

DOI
https://doi.org/10.3389/fimmu.2024.1394108
Journal volume & issue
Vol. 15

Abstract

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Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by persistent synovial inflammation and progressive joint destruction. Macrophages are key effector cells that play a central role in RA pathogenesis through their ability to polarize into distinct functional phenotypes. An imbalance favoring pro-inflammatory M1 macrophages over anti-inflammatory M2 macrophages disrupts immune homeostasis and exacerbates joint inflammation. Multiple signaling pathways, including Notch, JAK/STAT, NF-κb, and MAPK, regulate macrophage polarization towards the M1 phenotype in RA. Metabolic reprogramming also contributes to this process, with M1 macrophages prioritizing glycolysis while M2 macrophages utilize oxidative phosphorylation. Redressing this imbalance by modulating macrophage polarization and metabolic state represents a promising therapeutic strategy. Furthermore, complex bidirectional interactions exist between synovial macrophages and fibroblast-like synoviocytes (FLS), forming a self-perpetuating inflammatory loop. Macrophage-derived factors promote aggressive phenotypes in FLS, while FLS-secreted mediators contribute to aberrant macrophage activation. Elucidating the signaling networks governing macrophage polarization, metabolic adaptations, and crosstalk with FLS is crucial to developing targeted therapies that can restore immune homeostasis and mitigate joint pathology in RA.

Keywords