Regulatory effect of anti-gp130 functional mAb on IL-6 mediated RANKL and Wnt5a expression through JAK-STAT3 signaling pathway in FLS.

Ping Miao,Ninan Chen,Xiao Wei Zhou,Rong Zhao,Xue Hua Chen,Dong Qing Zhang,Mason Lu,Qi Wen Yu,Liu Qian,Rong Xu,Lian Bo Xiao,Pu Li,Ping Wang,Chao Ying Hu,Ji Ying Zhang,Dong Yi He

doi:10.18632/oncotarget.23917

Abstract

We investigated the effect on rheumatoid arthritis (RA) of an anti-gp130 monoclonal antibody (mAb) and its mechanism using RA fibroblast-like synoviocytes (FLS) and a collagen antibody–induced arthritis (CAIA) mouse model. We determined the interleukin 6 (IL-6), IL-6 receptor α (IL-6Rα), gp130, receptor activator of nuclear factor κB ligand (RANKL), matrix metalloproteinase 3 (MMP3), TIMP metallopeptidase inhibitor 1 (TIMP1), and Bcl-2 levels in RA and osteoarthritis (OA) serum and synovial fluid. RA FLS were cultured with or without IL-6/IL-6Rα; WNT5A and RANKL levels were detected. We generated an anti-gp130 mAb (M10) with higher affinity and specificity, blocked IL-6 signaling with it, and assessed its effects on the CAIA model, WNT5A and RANKL expression, and signal transducer and activator of transcription 3 (STAT3) phosphorylation. The IL-6 signaling system in patients with RA was increased; RANKL, MMP3, TIMP1, and Bcl-2 in RA bone were elevated. IL-6/IL-6Rα increased RA FLS WNT5A and RANKL expression. M10 ameliorated arthritis in the CAIA model, and inhibited RANKL, WNT5A, and Bcl-2 expression in RA FLS by blocking IL-6 signaling, likely via Janus kinase–STAT3 pathway downregulation. The IL-6–soluble IL-6Rα–gp130 complex is hyperactive in RA and OA. M10 may be the basis for a novel RA treatment drug.

Highlights

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease which is characterized by the invasion and proliferation of synoviocytes and resulting in bone and cartilage destruction [1]
We investigated the effect on rheumatoid arthritis (RA) of an anti-gp130 monoclonal antibody and its mechanism using RA fibroblast-like synoviocytes (FLS) and a collagen antibody–induced arthritis (CAIA) mouse model
These findings indicate that the interleukin 6 (IL-6) signaling system is increased in patients with RA, as sgp130 is a natural antagonist of the gp130 signaling system in RA

Summary

Introduction

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease which is characterized by the invasion and proliferation of synoviocytes and resulting in bone and cartilage destruction [1]. Inflammatory stimuli, especially IL-6, TNFα and IL-1, are potent FLS activators and can induce FLS to produce other cytokines, which in turn promotes autoimmunity, maintains chronic inflammatory synovitis, and drives bone and joint destruction [1]. RANKL mediated effects through binding to RANK on osteoclasts and their precursors surface [5, 6] Factors such as IL-6, TNFα, IL1, and IL-17 regulate RANKL expression and synthesis. Hashizume et al demonstrated that IL-6 can stimulate RANKL expression in FLS associated with soluble IL6R (sIL-6R) [7]. This suggests that IL-6 trans-signaling pathway might enhance osteoclastogenesis through elevated RANKL expression in the FLS of RA patients

Methods

Results

Conclusion