Viral dsRNA can be found at the site of inflammation in RA patients, and intra-articular injection of dsRNA induces arthritis by activating type I IFN signaling in mice. Further, DCs, a major source of IFN-α, can be found in the synovium of RA patients. We therefore determined the occurrence of DCs in dsRNA-induced arthritis and their ability to induce arthritis. Here, we show, by immunohistoch...

OBJECTIVES The aim of the present study was to determine the in vivo efficacy of p38 mitogen-activated protein kinase (MAPK) inhibitors, namely GW856553X and GSK678361, in murine models of arthritis. METHODS The effect of p38 MAPK inhibitors was tested in 2 variants of the collagen-induced arthritis model (CIA) in DBA/1 mice, acute arthritis induced by heterologous collagen and chronic relaps...

Intraarticular gene transfer of cyclin-dependent kinase (CDK) inhibitors to suppress synovial cell cycling has shown efficacy in treating animal models of rheumatoid arthritis. Endogenous CDK inhibitors also modulate immune function via a CDK-independent pathway. Accordingly, systemic administration of small molecules that inhibit CDK may or may not ameliorate arthritis. To address this issue, ...

The mechanism(s) by which Lyme arthritis is induced has not been elucidated. In this study, we showed that macrophages have a direct, effector role in the pathogenesis of Lyme arthritis. Severe destructive arthritis was induced in recipients of macrophages obtained from Borrelia burgdorferi-vaccinated and nonvaccinated hamsters exposed to Formalin-inactivated B. burgdorferi in vitro and then ch...

OBJECTIVE The Syk tyrosine kinase plays an important role in diverse functions in hematopoietic lineage cells. Although previous in vitro and pharmacologic analyses suggested Syk to be a possible player in the development of autoimmune arthritis, no in vivo genetic studies addressing that issue have yet been reported. The aim of the present study was to test whether genetic deficiency of Syk af...

Th2-eosinophil immune responses are well known for mediating host defence against helminths. Herein we describe a function of Th2-eosinophil responses in counteracting the development of arthritis. In two independent models of arthritis, Nippostrongylus brasiliensis infection leads to Th2 and eosinophil accumulation in the joints associated with robust inhibition of arthritis and protection fro...

Rheumatoid arthritis is a chronic autoimmune disease of unknown etiology characterized by chronic inflammation in the joints and subsequent destruction of the cartilage and bone. The present study proposes a new strategy for the treatment of arthritis: the administration of the immunomodulatory neuropeptide adrenomedullin. Treatment with adrenomedullin significantly reduced incidence and severi...

BACKGROUND The mechanisms underlying tolerance induction and maintenance in autoimmune arthritis remain elusive. In a mouse model of rheumatoid arthritis, collagen type II (CII)-induced arthritis, we explore the contribution of B cells to antigen-specific tolerance. METHODS To generate expression of the CII-peptide specifically on B-cell major histocompatibility complex type II, lentiviral-ba...