Skip to Content
Merck
  • Role of Chondrocytes in the Development of Rheumatoid Arthritis Via Transmembrane Protein 147-Mediated NF-κB Activation.

Role of Chondrocytes in the Development of Rheumatoid Arthritis Via Transmembrane Protein 147-Mediated NF-κB Activation.

Arthritis & rheumatology (Hoboken, N.J.) (2019-12-01)
Mitsutoshi Ota, Yuki Tanaka, Ikuma Nakagawa, Jing-Jing Jiang, Yasunobu Arima, Daisuke Kamimura, Tomohiro Onodera, Norimasa Iwasaki, Masaaki Murakami
ABSTRACT

We have previously reported that the coactivation of NF-κB and STAT3 in nonimmune cells, including synovial fibroblasts, enhances the expression of NF-κB target genes and plays a role in chronic inflammation and rheumatoid arthritis (RA). This study was undertaken to examine the role of NF-κB activation in chondrocytes and better understand the pathogenesis of RA. Furthermore, transmembrane protein 147 (TMEM147) was investigated as a representative NF-κB activator in chondrocytes. Clinical samples from RA patients were analyzed by immunohistochemistry. Specimens obtained from patients with polydactyly were used as control samples. The functional contribution of chondrocytes and TMEM147 to arthritis was examined in several murine models of RA. In vitro experiments (quantitative polymerase chain reaction, RNA interference, immunoprecipitation, and confocal microscopy) were performed to investigate the mechanism of action of TMEM147 in chondrocytes. Samples obtained from RA patients and mouse models of RA showed coactivation of NF-κB and STAT3 in chondrocytes (P < 0.001). This coactivation induced a synergistic expression of NF-κB targets in vitro (P < 0.01). Chondrocyte-specific deletion of STAT3 significantly suppressed the development of cytokine-induced RA (P < 0.01). TMEM147 was highly expressed in chondrocytes from RA patient samples and the mouse models of RA. Gene silencing of TMEM147 or anti-TMEM147 antibody treatment inhibited the cytokine-mediated activation of NF-κB in vitro (P < 0.01) and suppressed cytokine-induced RA in vivo (P < 0.01). Mechanistically, TMEM147 molecules acted as scaffold proteins for the NF-κB complex, which included breakpoint cluster region and casein kinase 2, and enhanced NF-κB activity. These results suggest that chondrocytes play a role in the development of RA via TMEM147-mediated NF-κB activation and indicate a novel therapeutic strategy for RA.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
3X FLAG® Peptide, lyophilized powder
Sigma-Aldrich
Monoclonal ANTI-FLAG® M2 antibody produced in mouse, 1 mg/mL, clone M2, affinity isolated antibody, buffered aqueous solution (50% glycerol, 10 mM sodium phosphate, and 150 mM NaCl, pH 7.4)
Sigma-Aldrich
MISSION® esiRNA, targeting human TMEM147
Sigma-Aldrich
MISSION® pLKO.1-puro Non-Mammalian shRNA Control Plasmid DNA, Targets no known mammalian genes
Sigma-Aldrich
Monoclonal Anti-α-Tubulin antibody produced in mouse, ascites fluid, clone B-5-1-2
Millipore
ANTI-FLAG® M2 Affinity Gel, purified immunoglobulin, buffered aqueous glycerol solution
Sigma-Aldrich
Anti-phospho-NF-kappaB p65 (pSer276) antibody produced in rabbit, affinity isolated antibody
Sigma-Aldrich
Anti-phospho-CK2α (pThr360/Ser362) antibody produced in rabbit, affinity isolated antibody