Inflammation and Immunity

A variety of diseases are caused by a chronic inflammatory response by the immune system. Hypersensitivity can result from chronic exposure to antigens. A breakdown in the mechanisms of "self-tolerance" can lead to autoimmune disorders. Transplant rejection and immunodeficiency can also arise from alterations in immune system function. Brief descriptions of a few common chronic inflammatory diseases are listed below.

Rheumatoid Arthritis¹

Rheumatoid arthritis (rue-ma-TOYD arth-write-tis) involves inflammation in the lining of the joints and/or other internal organs. RA typically affects many different joints. It is typically chronic, and can be a disease of flare-ups. RA is a systemic disease that affects the entire body and is one of the most common forms of arthritis. It is characterized by the inflammation of the membrane lining the joint, which causes pain, stiffness, warmth, redness and swelling. The involved joint can lose its shape and alignment, resulting in pain and loss of movement. The inflamed joint lining, the synovium, can invade and damage bone and cartilage, causing permanent joint damage with joint deformities and loss of function.

Less than 50 percent of working age adults with RA are still employed 10 years after disease onset. Mortality rates for people with RA are double that of the general population. Musculoskeletal conditions such as rheumatoid arthritis cost the U.S. economy nearly $86.2 billion per year in medical care and indirect expenses such as lost wages and production.

Lupus²

Lupus is a chronic (lifelong) autoimmune disease that, for unknown reasons, causes the immune system to attack the body's own tissue and organs, including the joints, kidneys, heart, lungs, brain, blood, or skin. Lupus is 10 to 15 times more frequent among women than men. The Lupus Foundation of America estimates that approximately 1,500,000 or 1 in every 200 Americans have a form of the disease. Although lupus can strike men and women of all ages, 90% of individuals diagnosed with the disease are women, and 80% of those afflicted with systemic lupus develop it between the ages of 15 and 45.

Approximately 70% of lupus cases are systemic. In about 50% of these cases, a major organ will be affected. About 5 percent of the children born to individuals with lupus will develop the illness. Lupus is two to three times more prevalent among people of color, including African Americans, Hispanics, Asians, and Native Americans.

Several studies suggest that the annual average cost to provide medical treatment for a person with lupus is between $6,000 and $10,000. For some people with lupus, however, medical costs may exceed several thousand dollars every month. Two out of three lupus patients report a complete or partial loss of their income because they are unable to work.

Psoriasis³

Psoriasis (sore-I-ah-sis) is a common immune-mediated chronic skin disease that comes in different forms and varying levels of severity. Psoriasis is a lifelong skin disease that occurs when faulty signals in the immune system cause skin cells to regenerate too quickly-every three to four days instead of the usual 30-day cycle. Extra skin cells build up on the skin's surface, forming red, flaky, scaly lesions that can itch, crack, bleed and be extremely painful. Psoriasis generally appears on the joints, limbs and scalp but it can appear anywhere on the body, covering some people from head to toe.

More than 5 million Americans, or 2-3% of the population have been diagnosed with psoriasis and/or psoriatic arthritis, a degenerative disease of the joints and connective tissues associated with psoriasis. Psoriasis typically first strikes people between the ages of 15 and 35, but can affect anyone at any age, including children. The most common form of psoriasis is called "plaque psoriasis," which is characterized by well-defined patches of red, raised skin. About 80 percent of people with psoriasis have this type. Plaque psoriasis can appear on any skin surface, although the knees, elbows, scalp, trunk and nails are the most common locations. Psoriatic arthritis is a specific type of arthritis that has been diagnosed in approximately 23 percent of people who have psoriasis, according to the Psoriasis Foundation's 2001 Benchmark Survey.

Chronic Obstructive Pulmonary Disease⁴

Chronic obstructive pulmonary disease (COPD) includes emphysema and chronic bronchitis--diseases that are characterized by obstruction to air flow. Emphysema and chronic bronchitis frequently coexist. Thus physicians prefer the term COPD. It does not include other obstructive diseases such as asthma. COPD, which is the fourth leading cause of death, claims the lives of 117,522 Americans annually.

Symptoms of chronic bronchitis include chronic cough, increased mucus, frequent clearing of the throat and shortness of breath. Females have significantly higher rates of chronic bronchitis than males. In 2001, 3.7 million men had a diagnosis of chronic bronchitis compared to 7.5 million women.

Emphysema causes irreversible lung damage. The walls between the air sacs within the lungs lose their ability to stretch and recoil. They become weakened and break. Elasticity of the lung tissue is lost, causing air to be trapped in the air sacs and impairing the exchange of oxygen and carbon dioxide. Also, the support of the airways is lost, allowing for obstruction of airflow. An estimated 3 million Americans have been diagnosed with emphysema sometime in their life. Of the emphysema sufferers, 57 percent are male and 43 percent are female. While more men suffer from the disease than women, the condition is increasing among women.

The annual cost to the nation for COPD is approximately $32.1 billion, including healthcare expenditures of $18.0 billion and indirect costs of $14.1 billion.

Icogenex is actively working to develop effective therapeutics for the treatment of these and other inflammatory diseases.

1. Arthritis Foundation
2. The Lupus Foundation of America
3. National Psoriasis Foundation
4. American Lung Association