Immunological therapies for rheumatoid arthritis.

Rheumatoid arthritis (RA) is a chronic inflammatory arthritis of the synovial joints that causes loss of function and a shortened life expectancy. In the last 10 years there have been major advances in the treatment of RA, including more aggressive use of disease-modifying anti-rheumatic drugs and the development of immune therapies targeted to molecules and cells important in the immunopathogenesis of RA. Molecular messengers that travel between cells (cytokines) have been found to be of major importance. Blocking the cytokine tumour necrosis factor alpha (TNF-alpha) produces significant improvement in RA, ankylosing spondylitis, psoriatic arthritis, psoriasis and Crohn's disease. The use of cytokine blockers has shown the extent to which immune and inflammatory pathways are shared in a number of inflammatory diseases. There has also been an important proof of principle that blocking single cytokines can produce profound effects in inflammatory diseases.