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Updated: Aug 25, 2026

Software-Assisted Quantitative Measurement of Osteoarthritic Subchondral Bone Thickness
08:52

Software-Assisted Quantitative Measurement of Osteoarthritic Subchondral Bone Thickness

Published on: March 18, 2022

Innate immune sensor NOD2 promotes cartilage degradation and osteoarthritis progression by stabilizing TRAF6 in

Yuting Wang1,2,3, Song Li1, Yonghui Dong4

  • 1Department of Orthopaedics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.

JCI Insight
|August 24, 2026
PubMed

Insights

Nucleotide-binding oligomerization domain 2 (NOD2) drives osteoarthritis inflammation and cartilage damage. Inhibiting NOD2 shows promise for disease-modifying osteoarthritis treatment.

Area of Science:

  • Immunology
  • Rheumatology
  • Molecular Biology

Background:

  • Inflammation is key in osteoarthritis (OA) pathogenesis, but mechanisms are unclear.
  • Current OA therapies offer only symptomatic relief, not disease modification.
  • Nucleotide-binding oligomerization domain 2 (NOD2) is an inflammatory pattern recognition receptor.

Purpose of the Study:

  • To investigate the role of NOD2 in OA-associated inflammation and cartilage degradation.
  • To explore NOD2 as a potential therapeutic target for OA.

Main Methods:

  • Assessed NOD2 expression in human and mouse OA cartilage.
  • Used conditional knockout of Nod2 in chondrocytes in vitro and in vivo OA models.
  • Identified downstream mediators of NOD2 signaling.
  • Tested small-molecule NOD2 inhibitors in vivo.

Main Results:

  • NOD2 expression was elevated in OA cartilage.
  • Chondrocyte-specific Nod2 deletion reduced inflammation and protected cartilage in OA models.
  • Tumor necrosis factor receptor-associated factor 6 (TRAF6) was identified as a key mediator.
  • NOD2 inhibition significantly attenuated OA progression in vivo.

Conclusions:

  • NOD2 is a critical regulator of OA inflammation and cartilage breakdown.
  • Targeting NOD2 offers a potential strategy for disease-modifying OA treatment.
Keywords:
Bone biologyCartilageCellular immune responseInflammationOsteoarthritis

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