Recent findings have substantiated the importance of T lymphocytes to the pathogenesis of
rheumatoid arthritis (RA). Here, we review emerging data regarding genetic predisposition,
spontaneous animal models of arthritis, and cell-cell interactions that implicate T cells as
driving synovial inflammation and joint destruction. Information regarding the
proinflammatory role of interleukin-17-producing T cells and the functional state of regulatory
T cells both in animal models and in patients with RA is also discussed. In light of the …

Rheumatoid arthritis (RA) is one of the inflammatory joint diseases in a heterogeneous
group of disorders that share features of destruction of the extracellular matrices of articular
cartilage and bone. The underlying disturbance in immune regulation that is responsible for
the localized joint pathology results in the release of inflammatory mediators in the synovial
fluid and synovium that directly and indirectly influence cartilage homeostasis. Analysis of
the breakdown products of the matrix components of joint cartilage in body fluids and …

The multitude and abundance of macrophage-derived mediators in rheumatoid arthritis and
their paracrine/autocrine effects identify macrophages as local and systemic amplifiers of
disease. Although uncovering the etiology of rheumatoid arthritis remains the ultimate
means to silence the pathogenetic process, efforts in understanding how activated
macrophages influence disease have led to optimization strategies to selectively target
macrophages by agents tailored to specific features of macrophage activation. This …

For some time synovial fibroblasts have been regarded simply as innocent synovial cells,
mainly responsible for synovial homeostasis. During the past decade, however, a body of
evidence has accumulated illustrating that rheumatoid arthritis synovial fibroblasts (RASFs)
are active drivers of joint destruction in rheumatoid arthritis. Details regarding the
intracellular signalling cascades that result in long-term activation and synthesis of
proinflammatory molecules and matrix-degrading enzymes by RASFs have been analyzed …