[Anti-interleukin-6 receptor antibody therapy--from bedside to bench]

Recent progress in immunology, utilizing molecular biology techniques, has elucidated the molecular mechanism of immune system. In the treatment of autoimmune diseases, molecular targeting therapies utilizing biologics such as monoclonal antibodies are now available. However, exact causes of the most autoimmune diseases are not known and there remain many issues which should be resolved. Interleukin-6 (IL-6) is a cytokine which regulates immune response and inflammation. Deregulated overproduction of IL-6 is involved in the immune-inflammatory diseases such as Castleman's disease and rheumatoid arthritis. A humanized anti-IL-6 receptor antibody tocilizumab has been proven to be therapeutically effective for the diseases. Simultaneously, we have learned new biological activities from the translational research. In this review, a study from bedside to bench is to be discussed.