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92 Innovative Rheumatology

**Chapter 5**

**Treatment of Rheumatoid Arthritis with**

The term "cytokine" is coined from the combination of "cyto", a prefix which means cell,

For example, both tumor necrosis factor (TNF) and interleukin-6 (IL-6) have synovial prolif‐

For example, TNF causes synovial proliferation, destroys articular cartilage, and promotes

Inflammatory cytokines play a central role in rheumatoid arthritis. In the treatment of rheu‐ matoid arthritis with biological agents, the effects of cytokines are suppressed by blocking

With respect to these cytokines, antibodies and antibody fusion proteins that inhibit the ac‐ tion of IL-1, IL-6, and TNF have already been commercialized, and development of an IL-17

and reproduction in any medium, provided the original work is properly cited.

© 2013 Matsuno; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use,

© 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution,

distribution, and reproduction in any medium, provided the original work is properly cited.

**1.** They are low-molecular-weight glycoproteins that are not hormones.

**4.** One cytokine can act on various organs at the same time (pleiotropy).

**5.** Each cytokine has a specific receptor and acts by binding to that receptor.

**3.** Different cytokines can have the same function (redundancy).

Additional information is available at the end of the chapter

**2.** They have an effect at very small concentrations.

eration activity and destroy articular cartilage and bone.

the cytokine from binding to its specific receptor (Figure 1).

inhibitor is underway (Figure 2,Table 1).

**Biological Agents**

http://dx.doi.org/10.5772/53321

*Cytokines and Rheumatoid Arthritis*

and "kine", which denotes movement. Cytokines all have the following features:

Hiroaki Matsuno

**1. Introduction**

fever.
