The immune system is the body's means of protection against microorganisms and other "foreign" substances. It is composed of two major parts. One component, B lymphocytes, produces antibodies, proteins that attack "foreign" substances and cause them to be removed from the body; this is sometimes called the humoral immune system. The other component consists of special white blood cells called T lymphocytes, which can attack "foreign" substances directly; this is sometimes called the cellular immune system. It takes time for both components of the immune system to develop. The only protections a newborn will have are the antibodies that have transferred from the mother to the baby before birth. T lymphocytes become protective, and antibodies are developed after a person is exposed to specific "foreign" threats. Over a lifetime, the immune system develops an extensive library of identified substances and microorganisms that are cataloged as “threat” or “not threat.” Vaccinations utilize this process to add to the library. They expose a person’s immune system to weakened or inactivated forms of bacteria and viruses that can no longer cause disease, so that the person’s immune system will recognize them and create antibodies that will be ready to protect against the infectious forms of these microorganisms if the person comes in contact with them in the future.
Normally, the immune system can distinguish between “self” and “not self” and only attacks those tissues that it recognizes as “not self.” This is usually the desired response, but not always. When a person is given an organ transplant, the immune system will correctly recognize the new organ as “not self” (unless it is from an identical twin) and will attack it in a process called rejection. To prevent rejection, the transplant patient must take drugs that reduce the activity of the immune system (immunosuppressants) for the rest of his life.
What are autoimmune disorders?
Autoimmune disorders are diseases caused by the body producing an inappropriate immune response against its own tissues. Sometimes the immune system will cease to recognize one or more of the body’s normal constituents as “self” and will create autoantibodies – antibodies that attack its own cells, tissues, and/or organs. This causes inflammation and damage and it leads to autoimmune disorders.
The cause of autoimmune diseases is unknown, but it appears that there is an inherited predisposition to develop autoimmune disease in many cases. In a few types of autoimmune disease (such as rheumatic fever), a bacteria or virus triggers an immune response, and the antibodies or T-cells attack normal cells because they have some part of their structure that resembles a part of the structure of the infecting microorganism.
Autoimmune disorders fall into two general types: those that damage many organs (systemic autoimmune diseases) and those where only a single organ or tissue is directly damaged by the autoimmune process (localized). However, the distinctions become blurred as the effect of localized autoimmune disorders frequently extends beyond the targeted tissues, indirectly affecting other body organs and systems. Some of the most common types of autoimmune disorders include:
Systemic Autoimmune Diseases Localized Autoimmune Diseases
Rheumatoid arthritis (RA) and Juvenile RA (JRA) (joints; less commonly lung, skin)
Type 1 Diabetes Mellitus (pancreas islets)
Lupus [Systemic Lupus Erythematosus] (skin, joints, kidneys, heart, brain, red blood cells, other)
Hashimoto's thyroiditis, Graves' disease (thyroid)
Scleroderma (skin, intestine, less commonly lung)
Celiac disease, Crohn's disease, Ulcerative colitis (GI tract)
Sjogren's syndrome (salivary glands, tear glands, joints)
Multiple sclerosis*
Goodpasture's syndrome (lungs, kidneys)
Addison's disease (adrenal)
Wegener's granulomatosis (blood vessels, sinuses, lungs, kidneys)
Primary biliary cirrhosis, Sclerosing cholangitis, Autoimmune hepatitis (liver)
Polymyalgia Rheumatica (large muscle groups)
Temporal Arteritis / Giant Cell Arteritis (arteries of the head and neck)
Guillain-Barre syndrome (nervous system)
* There is still some debate as to whether MS is an autoimmune disease
For a more complete list of autoimmune conditions, visit the Patient Information page of the American Autoimmune Related Diseases Association, Inc.
In some cases, a person may have more than one autoimmune disease; for example, persons with Addison's disease often have type 1 diabetes, while persons with sclerosing cholangitis often have ulcerative colitis.
In some cases, the antibodies may not be directed at a specific tissue or organ; for example, antiphospholipid antibodies can react with clotting proteins in the blood, leading to formation of blood clots within the blood vessels (thrombosis).
Autoimmune disorders are diagnosed, evaluated, and monitored through a combination of autoantibody blood tests, blood tests to measure inflammation and organ function, clinical presentation, and through non-laboratory examinations such as X-rays. There is currently no cure for autoimmune disorders, although in rare cases they may disappear on their own. Many people may experience flare-ups and temporary remissions in symptoms, others chronic symptoms or a progressive worsening. Treatment of autoimmune disorders is tailored to the individual and may change over time. The goal is to relieve symptoms, minimize organ and tissue damage, and preserve organ function. New treatments and a greater understanding of autoimmune disorders are being researched. Patients should talk to their doctors and to any specialists they are referred to about their treatment options.
For more information on specific autoimmune disorders, see the related condition pages and web sites listed below.
Normally, the immune system can distinguish between “self” and “not self” and only attacks those tissues that it recognizes as “not self.” This is usually the desired response, but not always. When a person is given an organ transplant, the immune system will correctly recognize the new organ as “not self” (unless it is from an identical twin) and will attack it in a process called rejection. To prevent rejection, the transplant patient must take drugs that reduce the activity of the immune system (immunosuppressants) for the rest of his life.
What are autoimmune disorders?
Autoimmune disorders are diseases caused by the body producing an inappropriate immune response against its own tissues. Sometimes the immune system will cease to recognize one or more of the body’s normal constituents as “self” and will create autoantibodies – antibodies that attack its own cells, tissues, and/or organs. This causes inflammation and damage and it leads to autoimmune disorders.
The cause of autoimmune diseases is unknown, but it appears that there is an inherited predisposition to develop autoimmune disease in many cases. In a few types of autoimmune disease (such as rheumatic fever), a bacteria or virus triggers an immune response, and the antibodies or T-cells attack normal cells because they have some part of their structure that resembles a part of the structure of the infecting microorganism.
Autoimmune disorders fall into two general types: those that damage many organs (systemic autoimmune diseases) and those where only a single organ or tissue is directly damaged by the autoimmune process (localized). However, the distinctions become blurred as the effect of localized autoimmune disorders frequently extends beyond the targeted tissues, indirectly affecting other body organs and systems. Some of the most common types of autoimmune disorders include:
Systemic Autoimmune Diseases Localized Autoimmune Diseases
Rheumatoid arthritis (RA) and Juvenile RA (JRA) (joints; less commonly lung, skin)
Type 1 Diabetes Mellitus (pancreas islets)
Lupus [Systemic Lupus Erythematosus] (skin, joints, kidneys, heart, brain, red blood cells, other)
Hashimoto's thyroiditis, Graves' disease (thyroid)
Scleroderma (skin, intestine, less commonly lung)
Celiac disease, Crohn's disease, Ulcerative colitis (GI tract)
Sjogren's syndrome (salivary glands, tear glands, joints)
Multiple sclerosis*
Goodpasture's syndrome (lungs, kidneys)
Addison's disease (adrenal)
Wegener's granulomatosis (blood vessels, sinuses, lungs, kidneys)
Primary biliary cirrhosis, Sclerosing cholangitis, Autoimmune hepatitis (liver)
Polymyalgia Rheumatica (large muscle groups)
Temporal Arteritis / Giant Cell Arteritis (arteries of the head and neck)
Guillain-Barre syndrome (nervous system)
* There is still some debate as to whether MS is an autoimmune disease
For a more complete list of autoimmune conditions, visit the Patient Information page of the American Autoimmune Related Diseases Association, Inc.
In some cases, a person may have more than one autoimmune disease; for example, persons with Addison's disease often have type 1 diabetes, while persons with sclerosing cholangitis often have ulcerative colitis.
In some cases, the antibodies may not be directed at a specific tissue or organ; for example, antiphospholipid antibodies can react with clotting proteins in the blood, leading to formation of blood clots within the blood vessels (thrombosis).
Autoimmune disorders are diagnosed, evaluated, and monitored through a combination of autoantibody blood tests, blood tests to measure inflammation and organ function, clinical presentation, and through non-laboratory examinations such as X-rays. There is currently no cure for autoimmune disorders, although in rare cases they may disappear on their own. Many people may experience flare-ups and temporary remissions in symptoms, others chronic symptoms or a progressive worsening. Treatment of autoimmune disorders is tailored to the individual and may change over time. The goal is to relieve symptoms, minimize organ and tissue damage, and preserve organ function. New treatments and a greater understanding of autoimmune disorders are being researched. Patients should talk to their doctors and to any specialists they are referred to about their treatment options.
For more information on specific autoimmune disorders, see the related condition pages and web sites listed below.
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