Psoriasis Psoriatic Arthritis

An Introduction to Tumor Necrosis Factor-Alpha for Psoriatic Arthritis

Medically Reviewed On: December 22, 2010

Doctors investigating what takes place in the body during the progression of psoriatic arthritis (PsA) have discovered that a specific protein called tumor necrosis factor-alpha (TNF-alpha) plays a central role. Tumor necrosis factor-alpha is involved in the body’s inflammatory process and has been linked to several chronic inflammatory conditions, including rheumatoid arthritis. In recent years, doctors have found evidence that TNF-alpha is also linked to psoriatic arthritis, and it is presently considered to be an important indicator of the disease. High concentrations of TNF-alpha can be found in the skin, in blister fluid and in the synovial fluid that lines the joints of patients with psoriatic arthritis,. Fortunately, doctors have discovered that the more TNF-alpha present, the more severe the damage from the disease is likely to be.

How the Immune System Works
Tumor necrosis factor-alpha is produced naturally in the body by multiple cells. In a normal immune system, it works together with other cells, tissues and organs to protect the body from infection and disease. The immune system cells do this by identifying and attacking foreign substances, such as bacteria, viruses, parasites and fungi.

When a foreign substance, also known as an antigen, is present, it activates a specific type of white blood cell called a T-cell. These cells, considered by many to be the “generals” of the immune system, are in charge of coordinating the immune response which will neutralize a foreign substance.

One part of this response includes the release of interleukins, which are types of cytokines or nonantibody proteins that the immune system uses to communicate messages. One of these cytokines is TNF-alpha.

A healthy immune system can clear itself of TNF-alpha, but in psoriatic arthritis, something happens to activate the T-cells to work overtime. As a result, they begin acting as if they are fighting off an infection, which in turn, signals the production of an excess amount of TNF-alpha. As TNF-alpha builds up, the messages it communicates create a cascade of events, which send more and more T-cells to the affected area.

In psoriasis, the result is the rapid growth of skin cells. Skin cells can grow up to 10 times faster than normal in people with psoriasis. When this occurs, the cells pile up at the skin's surface and lesions form. In psoriatic arthritis, the overproduction of TNF-alpha and the mixed messages it communicates results in joint inflammation, which usually produces joint pain and stiffness, tissue damage and other symptoms associated with psoriatic arthritis.

Page 1 of 2 Next Page >>