Suppression of arthritic bone destruction by adenovirus-mediated csk gene transfer to synoviocytes and osteoclasts

Abstract

Rheumatoid arthritis (RA) is characterized by a chronic inflammation of the synovial joints resulting from hyperplasia of synovial fibroblasts and infiltration of lymphocytes, macrophages, and plasma cells, all of which manifest signs of activation. Recent studies have revealed the essential role of osteoclasts in joint destruction in RA. Src family tyrosine kinases are implicated in various intracellular signaling pathways, including mitogenic response to growth factors in fibroblasts, activation of lymphocytes, and osteoclastic bone resorption. Therefore, inhibiting Src activity can be a good therapeutic strategy to prevent joint inflammation and destruction in RA. We constructed an adenovirus vector carrying the csk gene, which negatively regulates Src family tyrosine kinases. Csk overexpression in cultured rheumatoid synoviocytes remarkably suppressed Src kinase activity and reduced their proliferation rate and IL-6 production. Bone-resorbing activity of osteoclasts was strongly inhibited by Csk overexpression. Furthermore, local injection of the virus into rat ankle joints with adjuvant arthritis not only ameliorated inflammation but suppressed bone destruction. In conclusion, adenovirus-mediated direct transfer of the csk gene is useful in repressing bone destruction and inflammatory reactions, suggesting the involvement of Src family tyrosine kinases in arthritic joint breakdown and demonstrating the feasibility of intervention in the kinases for gene therapy in RA.

Cardiomyocyte Apoptosis Triggered by RAFTK/pyk2 via Src Kinase Is Antagonized by Paxillin

“…We previously observed that Src activation in vivo can be detrimental (19). Csk-expressing adenovirus, which inhibits Src by phosphorylation of Tyr 527 , has been shown to block apoptotic signaling (20,21). Csk also influences paxillin phosphorylation (22)(23)(24), although the cellular impact of this regulation remains to be elucidated.…”

Apoptosis as a target for gene therapy in rheumatoid arthritis

“…These include interference with the Ras-Raf MAPK pathway (Jorgensen & Gay 1998) and inhibition of the Src tyrosine kinase (Takayanagi et al 1999). These have been implicated in several biological functions, including mitogenic response to growth factors and cytokines, activation of lymphocytes and osteoclastic bone resorption.…”

“…The kinase activity of Src is negatively regulated by phosphorilation with another cytoplasmic tyrosine kinase named Csk (Cterminal Src kinase). Adenovirus-mediated overexpression of Csk tyrosine kinase dramatically reduced the proliferation rate and inflammatory activity in the joint by suppressing Src activity and almost completely repressed the bone-resorbing activity of osteoclasts (Takayanagi et al 1999). Recently, Taniguchi et al (1999) have also shown that cyclin-dependent kinase inhibitors, such as p16 INK4a gene can be used by gene transfer to suppress synovial cell proliferation.…”

“…E-mail: gabyrabi@ciudad.com.ar Received 7 August 2000 Accepted 4 September 2000 pro-inflammatory cytokines and metalloproteinases and by inducing osteoclast formation and activation . The activated phenotype of synovial cells is marked by an upregulation of proto-oncogenes, which are involved in important cellular events such as intracellular signaling and gene transcription (Takayanagi et al 1999).…”

Effects of the Sri Lankan medicinal plant, Salacia reticulata, in rheumatoid arthritis

“…Pannus releases several proinflammatory mediators, matrix metalloproteinase (MMP), immune modulatory factors and bone metabolism-related factors [27]. It was thought that osteoclastogenesis is enhanced by release of factors such as ILs, TNF-a and receptor activator of nuclear factor-kappa B ligand (RANKL) from pannus [23]. Activated osteoclasts have been shown to stain for tartrate-resistant acid phosphatase [25].…”