- Autoimmune Disorders That Affect the Blood
- Blood disorders and blood-related terms
- T-cells, B-cells, and Antibodies
- Antiphospholipid syndrome – APS
- Autoimmune disease – retraining white blood cells
- The Immune System and Multiple Sclerosis
Your doctor will do a physical exam and consider symptoms that you have along with your past medical issues to figure out what’s behind your result.
Bone marrow problems: The spongy center of your bones, which is called the bone marrow, makes blood cells. Low WBC counts are often linked to bone marrow problems. Being around certain chemicals, like benzene and pesticides, as well as some types of cancer and cancer treatments including chemotherapy and radiation, can hurt your bone marrow’s ability to make WBCs.
Autoimmune disorders: Some autoimmune diseases, like lupus and rheumatoid arthritis, will tell your body to attack and destroy its own WBCs.
Infection: Viruses can affect your bone marrow and cause low WBCs for a while. Severe infections, like blood infections, can lead to your body using up WBCs faster than it can make them. HIV kills a specific kind of white blood cell.
Medicines: Some drugs, including antibiotics, can destroy WBCs.
Nutrition: Not eating well or low levels of certain vitamins, such as folic acid and B12, can affect how your body makes WBCs. Alcohol abuse can mess with the nutrients in your body and with WBC counts, too.
Spleen problems: The spleen also makes WBCs. Infections, blood clots, and other problems can make it swell and not work the way it should. This will drop your WBC count.
Autoimmune Disorders That Affect the Blood
Autoimmune disorders can affect virtually every part of the body, and blood and blood vessels are no exception.
“These are relatively uncommon disorders,” says Alex Limanni, MD, a rheumatologist with Baylor University Medical Center in Dallas. “However, in their most severe forms, they can be life-threatening.”
Common Blood-Related Autoimmune Disorders
Here are some of the most common autoimmune disorders affecting the blood and circulatory system:
Lupus. Also known as systemic lupus erythematosus, lupus is a condition in which immune system attacks healthy tissue. “It can affect a number of different organs from top to bottom, including the brain, heart, lungs, joints, and kidneys,” Dr. Limanni says. Estimates put the number of Americans with lupus at 1.5 million.
Lupus can cause inflammation of the blood vessels, a condition known as vasculitis, which can damage the vessels. “That’s why we think many patients with lupus have a higher risk of coronary artery disease,” Limanni says.
Lupus can also affect the blood by lowering white blood cell and platelet counts. Some lupus patients develop anemia, a condition in which red blood cells are too low in number to adequately carry oxygen to the body’s tissues. Lupus patients may also have hemolytic anemia, which happens when the immune system attacks and destroys healthy red blood cells.
Medications are available for the treatment of lupus. For patients who develop vasculitis with their lupus, doctors will often prescribe Azasan or Imuran (azathioprine), which work by suppressing the immune system.
Lupus patients who develop hemolytic anemia can be treated with high doses of steroids to prevent red blood cell destruction, Limanni says. Some people with low platelet counts can also be treated with a splenectomy, a surgical procedure that removes the spleen.
Symptoms of lupus include extreme tiredness, anemia, and swollen joints. If you have these symptoms and suspect you have lupus, consult a physician.
Antiphospholipid antibody syndrome. Known as APS, this condition occurs when the body’s immune system mistakenly attacks phospholipid, a type of fat that is present in all living cells. In some cases, the attacks can cause clotting in the blood vessels and may lead to serious conditions such as stroke or heart attack. Women who have APS may also find that they have trouble carrying a pregnancy to term. About 1 to 5 percent of the general population is thought to have APS.
In many cases, the disease doesn’t cause any unwanted effects, and it’s only through routine blood tests that the APS antibodies are discovered. “Often, it’s a problem that doesn’t require therapy,” Limanni says.
People who do find that their APS is creating health problems can be treated with anticoagulants, or medicines that thin the blood. One of the most common blood thinners prescribed is Coumadin (warfarin). Women whose APS interferes with pregnancy are usually prescribed an injectable blood thinner like Lovenox (enoxaparin).
Symptoms of APS relate to blood clots and can include chest pain, shortness of breath, and pain or swelling in the limbs. If your doctor suspects that you have APS, a blood test can confirm the diagnosis.
Vasculitis. Vasculitis occurs when the immune system attacks healthy blood vessels and the inflamed vessels can then narrow or even burst. Vasculitis is considered a rare disease, affecting less than 200,000 people in the United States.
Vasculitis is most commonly categorized by the sizes of the blood vessels affected by the inflammation. Small-vessel vasculitis, for example, damages the smallest vessels in the body, like the capillaries. Symptoms of small-vessel vasculitis range from mild to severe. “It can be anything from a fairly limited disease that causes purpura, or purple lesions in the skin, to a condition that causes abdominal bleeding and pulmonary hemorrhage,” Limanni says.
Medium- and large-vessel vasculitis are less common, but more dangerous. “They will frequently involve blood vessels that supply the heart, lungs, kidneys, brain, and liver, so they can lead to stroke, heart attack, and renal failure.” says Limanni.
Mild forms of vasculitis can be treated with antimalarials like Plaquenil (hydroxychloroquine), immunosuppresssants like Azasan or Imuran, or steroids like prednisone. Medium- and large-blood-vessel vasculitis may call for more aggressive therapy. According to Limanni, “Treatment is going to consist of steroids and a chemotherapy-type immunosuppressant, like cyclophosphamide (Cytoxan, Neosar).”
Symptoms of vasculitis include fever, weight loss, and aches and pains. If vasculitis is affecting your skin, you may notice purple or red spots. If it affects your lungs, you may feel shortness of breath. To make a definitive diagnosis of vasculitis, your doctor can perform a biopsy to check for damage to the blood vessels, or a blood test to check for certain substances in the blood. Levels of antineutrophil cytoplasmic antibodies, or ANCA, are often elevated in people with vasculitis, for example.
Autoimmune hemolytic anemia. Known as AIHA, this condition occurs when the immune system creates antibodies that destroy red blood cells. Because red blood cells carry oxygen to the body’s tissues, AIHA can result in a reduced amount of oxygen in the body. It can also make the heart work harder to move blood through the body, potentially causing heart problems. At least 1 in 80,000 people are thought to develop AIHA each year.
Very mild forms of AIHA often don’t require treatment. But if medications are requuire, people are often treated with steroids like prednisone or drugs like Myfortic or CellCept (mycophenolate), which work by suppressing the immune system.
Signs of AIHA are often the same as the symptoms of other types of anemia, and may include fatigue, dizziness, and jaundice (a yellowing of the skin or whites of the eyes). One way to diagnose AIHA is by examining a small amount of your blood under a microscope — a procedure known as a peripheral smear. “They’ll look at the red blood cells and see whether there is evidence of destruction,” Limanni says.
If you notice the symptoms of any of these blood and blood vessel autoimmune disorders, contact your doctor. All of these conditions are treatable — and the sooner you know what is causing your symptoms, the sooner that treatment can begin.
Acute Sudden onset of symptoms or disease. Anemia A condition of the blood caused by a deficiency of red blood cells. Antibody A protein substance normally formed by the body to help defend it against disease. Excessive production of an abnormal antibody can cause disease. Antigen A protein that prompts the body to produce antibodies. Anti-inflammatory A medication that helps to reduce inflammation of tissue in the body. Autoimmune disorder Diseases caused by the immune system producing antibodies against the tissue of its own body. Basophils A type of white blood cell that plays a special role in allergic reactions. B-lymphocytes A type of lymphocyte, or white blood cell, used by the immune system. B-cells secrete antibodies into the body fluid to fight foreign substances that cause infections, disease, or poisoning. Biological therapy A treatment that stimulates the body’s own immune system to fight cancer or blood disorders. Blood count A blood test used to determine the number of the various types of blood cells. Blood transfusions Infusion of blood or blood components directly into the bloodstream to remedy blood loss or to treat anemia. Blood-clotting factors Components of plasma that are involved in the clotting of blood. Bone marrow The spongy substance in the inner cavity of bone which produces red blood cells, white blood cells, and platelets. Bone marrow biopsy A test where a needle is inserted into the bone of the hip or sternum (breastbone) to obtain a marrow sample for microscopic study and examination. Chemotherapy A treatment using medicines. Deciliter 1/10 of a liter. Eosinophils A type of white blood cell that plays a role in allergic reactions to foreign substances. Erythrocytes (red blood cells) The cells that carry oxygen. Essential thrombocythemia A disorder that causes an overproduction of platelets. External beam radiation therapy Treating cancer and other disorders with the use of radiation. Sometimes it is called radiation therapy. Extramedullary hematopoiesis Formation of blood cells outside of the bone marrow, such as in the spleen. Femtoliters 1/1,000,000,000,000,000 of a liter (this is very small!). Genetic disorder A disorder passed down in genes through generations of a family. Gout A painful inflammation in the joints, usually caused by an excessive amount of uric acid in the body. Gram A unit of mass, approximately equivalent to the weight of a paperclip. Hematologist A doctor who specializes in the study of blood and bone marrow. Hormonal therapy A treatment that uses the body’s hormones to treat cancer. This can be done by medication, surgical removal of the hormone-producing glands, or radiation therapy. Idiopathic myelofibrosis (MF) A disorder that causes the bone marrow to gradually be replaced with fibrous scar tissue and the spleen or liver to become enlarged. Idiopathic thrombocytopenic purpura A disorder that causes the immune system to make antibodies that destroy platelets, a type of blood cell. When the platelets are destroyed, a person is more susceptible to easy bruising and bleeding. Immune System A complex group of cells and substances that protect the body from infection and disease. Immunotherapy A treatment that stimulates the body’s immune system to fight cancer. Intravenous Into a vein. Leukocytes White blood cells. Liter Approximately equal to a quart. Lymphocytes A type of white blood cell. Three important kinds of lymphocytes are T-cells, B-cells, and Natural Killer Cells. T-cells attack and destroy virus-infected cells, foreign tissue and cancer cells; B-cells produce antibodies that help destroy foreign substances; Natural Killer cells destroy cancer cells and virus-infected cells. Microangiopathy The clotting of blood in the small blood vessels of organs. Microliter 1/100,000 of a liter. In a blood test, a microliter is a single drop of blood. Monoclonal antibody Monoclonal antibodies are a type of biological therapy produced in the laboratory. In ITP and macroglobuliemia, monoclonal antibodies are used to decrease the number of cells producing inappropriate antibodies. Monocytes A type of white blood cell. Neutrophils A mature white blood cell that fights bacterial infections. Neutrophils are also called segmented neutrophils or segs. Petechiae Small areas of pinpoint bleeding on the skin. This can be due to low platelet counts. Phlebotomy The removal of blood from a vein. Picograms 1/100,000,000,000 of a gram (this is very small!). Plasma The fluid part of blood. Plasma exchange In plasma exchange, blood is filtered through a machine that removes plasma and replaces it with plasma from healthy blood donors. Plasmapheresis During this procedure, blood is filtered through a machine that removes the antibody-containing plasma and replaces it with a substitute. Plasmapheresis can be used to temporarily reduce the amount of antibodies in the blood. Plateletpheresis A blood bank procedure that removes platelets from the blood. Platelets (Thrombocytes) A blood cell that assists in blood clotting. Patients are at risk to bleed if the platelet count is less than 50,000. Polycythemia vera (PV) A type of blood disorder that causes an excess of red blood cells. Some patients may also have an increased number of white blood cells and platelets. Radioactive Giving off high-dose energy in the form of particles. Radioactive substances can be used in the treatment of some blood disorders. Red blood cells (Erythrocytes) The blood cells that carry oxygen and are responsible for the red color of the blood. Splenectomy Surgical removal of the spleen. Thrombocytes (Platelets) Cells used to make the blood clot. Thrombotic thrombocytopenic purpura (TTP) A disorder of multiple clots in small blood vessels of many organs of the body. Ultraviolet light Light that is beyond the visible spectrum. Waldenstrom’s macroglobulinemia A rare disease that starts in the bone marrow and causes a rapid growth of B-lymphocytes, a type of white blood cell. White blood cells Blood cells used by the immune system to fight bacteria and viruses.
The immune system is an elaborate network of cells, tissues, and organs that helps to protect the body from invaders (bacteria, viruses, fungal infections, and parasites). Usually, the immune system develops only to act upon foreign substances, and immune system cells that try to combat cells of the body are weeded out during the development process. However, in lupus and other autoimmune diseases, the immune system begins to recognize and attack “self.” In other words, the cells of the immune system begin to injure the body’s own tissues. This phenomenon is similar to “friendly fire” and can cause permanent scarring that ultimately jeopardizes the function of certain organs and systems in the body. Certain cells and processes of the immune system have been identified as playing a role in lupus.
T-cells, B-cells, and Antibodies
A group of white blood cells called lymphocytes plays a key role in the human immune response. Lymphocytes include cells called B-cells and T-cells that are responsible for flagging and fighting infections in healthy individuals.
Antigens are substances that elicit the response of T-cells and B-cells in the body. When a T-cell recognizes a specific antigen, it binds to the substance and produces chemicals called cytokines. Cytokines then cause B-cells to multiply, and some of these B cells turn into plasma cells that secrete antibodies (immunoglobulins). These antibodies then circulate in the bloodstream so that when they encounter the antigen again, they bind to it, forming a complex that is then acted on by other cells of the immune system in an effort to destroy the invader. Usually, remnants of these complexes are removed from the body by a garbage disposal system that involves the spleen.
T-cells are classified as killer-T cells, helper-T cells, or suppressor T-cells. Killer-T cells have the ability to recognize and destroy infected cells in the body. Helper-T cells, however, can only identify viruses engulfed by special cells called macrophages. The macrophage presents the antigen to the helper-T cell, which responds by producing the cytokines that stimulate B cells to multiply and release antibodies.
In healthy individuals, the masses of cells that gather at an infected or injured site in the body produce factors that help fight off the infection. This process causes some inflammation and injury of healthy tissue, but usually the immune system possesses other factors that help to control this inflammatory process. In individuals with lupus, both B cells and T cells become overactive. The two main consequences of this increased activity are the production of autoantibodies (antibodies that recognize and destroy the body’s own cells) and inflammation that can lead to long-term, irreversible scarring.
The production of autoantibodies in people with lupus and other autoimmune diseases causes the immune system to target the body’s own cells for destruction. For example, about 98% of people with lupus possess antinuclear antibodies (ANA), which can attack the nucleic material of your cells. In addition, some individuals may possess anti-phospholipid antibodies, which damage proteins bound to phospholipids in the membranes of your cells. These autoantibodies are linked to pregnancy complications, stroke, heart attacks, and other blood clots.
In addition, regulatory T cells, which are supposed to control the system, are deficient in SLE.
Neutrophils are the most common type of white blood cell in your body; whereas lymphocytes are involved in the ongoing immune response, neutrophils are the first line of attack against invaders. Inflammation in a healthy individual usually signals that the body’s immune system is responding appropriately to pathogens, damaged cells, irritants, or injury. However, in lupus, neutrophils cause increased inflammation due to certain interactions between an individual’s blood plasma and other immune system cells (specifically, complement, cytokines, and cell adhesion molecules). Even though increased inflammation may cause pain and discomfort, the major problem with inflammation is potential long-term irreversible scarring. It is important that you and your doctor discuss medications to curb the inflammatory processes involved in lupus in order to minimize long-term damage to important organs.
Cytokines are signaling molecules involved in regulation of an individual’s immune response. Some cytokines amplify the immune response, while others tone it down. Some people with lupus and similar autoimmune diseases have a greater ratio of proinflammatory to anti-inflammatory cytokines than normal individuals, which produces an unbalanced regulatory mechanism.
While an overall cause-and-effect relationship between cytokines and lupus is not yet understood, certain cytokines called interferons and interleukins are associated with the disease. In general, however, the overproduction of such molecules causes the immune system to become overactive, leading to increased inflammation and tissue injury.
Complement proteins interact in a sequential manner to clear immune complexes from your body. Deficiencies of certain complement proteins are associated with lupus. In addition, since complement proteins are consumed during inflammatory processes, low complement levels may indicate lupus activity.
Having an autoimmune disease means that a person’s immune system is attacking their body instead of protecting it. Aside from the autoimmune disease they may have, they’re also at a higher risk of developing other serious health complications. According to prevention.com, here are five serious complications that can arise if you have an autoimmune disease.
Many of the autoimmune diseases which cause inflammation like lupus, scleroderma and rheumatoid arthritis, can lead to hardening of the arteries and can attack the heart muscle and lead to heart disease.
To help minimize the risk of heart disease, autoimmune patients should ensure they eat a heart-healthy diet and try to exercise as much as possible. They will also need to regularly monitor their blood sugar levels, cholesterol levels, and blood pressure.
Studies have found that people who have an autoimmune disease are six times more likely to develop a blood clot in the lungs following hospitalization. Multiple sclerosis and other autoimmune disease patients who are in a wheelchair or fairly sedentary are at risk of developing blood clots in the legs which can then travel up to the lungs. Compression socks or blood thinning medications may be advised by your doctor.
MORE: Four possible causes of multiple sclerosis.
The chronic pain and fatigue associated with autoimmune diseases can often lead to patients developing depression. It’s important that you speak to your doctor if you begin to experience anxiety or depression so that you can be treated as soon as possible and improve your quality of life.
Because patients with autoimmune diseases have a compromised immune system, they are at risk of developing certain cancers including lymphoma and breast cancer. It’s thought that inflammation in the body can trigger cells to multiply, which increases the risk of cell mutation.
Other Autoimmune Diseases
Sadly, if you already have an autoimmune disease there is an increased risk of developing one or even more autoimmune diseases. There are over 80 autoimmune diseases and those who suffer from three or more are said to have multiple autoimmune syndrome.
MORE: Seven strange and unusual symptoms of multiple sclerosis.
Multiple Sclerosis News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or another qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.
Relatively rare, but increasingly studied, blood clotting disorders present at birth can create problems throughout your life.
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These disorders usually cause blood clots in veins including deep vein thrombosis (DVT) of the arms or legs, pulmonary embolism, and blood clots in the brain, intestines and kidneys. They rarely cause blood clots in the arteries.
How clotting works
When you sustain an injury or cut, important components in your blood such as platelets and plasma including fibrinogen and other factors help to stop blood loss. They do this by thickening up the blood and forming a clot.
However, the blood shouldn’t clot when it’s just moving through the body. If blood tends to clot too much, it is referred to as a hypercoagulable state. The term thrombophilia describes a hypercoagulable state when it is due to the presence of abnormal clotting factors in the blood. These abnormal clotting factors may be due to inherited or acquired conditions.
Top inherited clotting disorders
John Bartholomew, MD, Section Head of Vascular Medicine and Director of the Thrombosis Center at Cleveland Clinic, says there are two common genetic causes of excessive clotting and several others that are identified less frequently.
Dr. Bartholomew says, “We are now looking closely at the specific causes behind clotting disorders, and our ever-increasing knowledge of genetics allows us to differentiate one disease from another, to identify the cause behind the symptoms.”
Though all occur rarely, Factor V Leiden and prothrombin gene mutation occur most often. Less common are: antithrombin, protein C and protein S deficiencies.
- Factor V Leiden: In Factor V Leiden, the normal checks and controls on a blood clotting substance known as Factor V are inactivated. In this particular case, genetic flaws inhibit a protein that normally keeps Factor V under control. As a result, blood clotting lasts longer than normal. Between 3 -8 percent of the population with European ancestry carries the gene mutation associated with the disorder.
- Prothrombin gene mutation: Patients with this disorder have a genetic defect that results in an overabundance of a blood clotting protein called prothrombin (also called Factor II). About 2 percent of Caucasians have some form of this disorder, which most often causes clots in the veins.
- Antithrombin deficiency (formerly called Antithrombin III) Protein C and Protein S deficiencies: These 3 are much less common (each found in less than 1% of the population in general). Clinical symptoms develop in early adulthood although patients with these disorders remain at risk for blood clots throughout their lifetime.
An acquired disorder
According to Dr. Bartholomew, “One of the most concerning thrombophilia disorders is the antiphospholipid syndrome.” It is an acquired condition, meaning it is not inherited. It is not clear why some people develop this condition, but it has been associated with infections, cancer, medications and some rheumatological conditions such as systemic lupus erythematosus.
In this complex syndrome, the body attacks substances called phospholipids that play a vital role in the integrity of cell wall membranes. As a result, blood cells degrade and then cause repeated clotting (thrombosis) in both the veins and arteries. This disorder can impact multiple systems in the body.
Even if you have a blood clotting disorder, you most likely will only need treatment when a blood clot develops. Anticoagulant drugs help prevent additional clots because they decrease the blood’s ability to coagulate. These drugs include:
- Warfarin (Coumadin®)
- Low-molecular weight heparin
- Fondaparinux (Arixtra®)
There are a number of newer blood thinning drugs approved by the FDA and available for use. These include: dabigatran (Pradaxa®), rivaroxaban (Xarelto®) and apixaban (Eliquis®).
Your doctor will talk to you about the benefits and risks of these medications. This information, along with your diagnosis, will help determine the type of medication you will take, how long you will need to take it, and the type of follow-up monitoring you need.
As with any medication, it is important to know how and when to take it according to your doctor’s guidelines. It’s also important to have frequent blood tests that your doctor orders.
Antiphospholipid syndrome – APS
The treatment for APS is directed at preventing complications from new blood clots forming or existing clots getting larger. You will need to take some form of blood-thinning medicine. If you also have an autoimmune disease, such as lupus, you will need to keep that condition under control as well.
The exact treatment will depend on how severe your condition is and the complications it is causing.
ANTIPHOSPHOLIPID ANTIBODY SYNDROME (APS)
In general, you will need treatment with a blood thinner for a long time if you have APS. Initial treatment may be heparin. These medicines are given by injection.
In most cases, warfarin (Coumadin), which is given by mouth, is then started. It is necessary to frequently monitor the level of anticoagulation. This is most often done using the INR test.
If you have APS and become pregnant, you will need to be followed closely by a provider who is an expert in this condition. You will not take warfarin during pregnancy, but will be given heparin shots instead.
If you have SLE and APS, your provider will also recommend that you take hydroxychloroquine.
Currently, other types of blood thinning medicines are not recommended.
CATASTROPHIC ANTIPHOSPHOLIPID SYNDROME (CAPS)
Treatment for CAPS that involves a combination of anticoagulation therapy, high doses of corticosteroids, and plasma exchange has been effective in most people. Sometimes IVIG, rituximab or eculizumab is also used for severe cases.
POSITIVE TEST FOR LUPUS ANTICOAGULANT OR APL
You will not need treatment if you do not have symptoms, pregnancy loss, or if you have never had a blood clot.
Take the following steps to help prevent blood clots from forming:
- Avoid most birth control pills or hormone treatments for menopause (women).
- DO NOT smoke or use other tobacco products.
- Get up and move around during long plane flights or other times when you have to sit or lie down for extended periods.
- Move your ankles up and down when you can’t move around.
You will be prescribed blood-thinning medicines (such as heparin and warfarin) to help prevent blood clots:
- After surgery
- After a bone fracture
- With active cancer
- When you need to sit or lie down for long periods of time, such as during a hospital stay or recovering at home
You may also need to take blood thinners for 3 to 4 weeks after surgery to lower your risk of blood clots.
Autoimmune disease – retraining white blood cells
How can the immune system be reprogrammed once it starts to attack its own body? EPFL scientists retrained white blood cells responsible for type I diabetes, a common autoimmune disease. Using a modified protein, they precisely targeted these white blood cells (T-lymphocytes, or T-cells) that were attacking pancreatic cells and causing the disease. When tested on laboratory mice, the therapy eliminated all signs of the pathology. This same method could be extremely promising in treating multiple sclerosis as well. The scientists have just launched a start-up Anokion SA on the Lausanne campus, and are planning to conduct clinical trials within the next two years. Their discovery has been published in the journal PNAS (Proceedings of the National Academy of Science).
To retrain the rebellious white blood cells, the researchers began with a relatively simple observation. Every day, thousands of our cells die. Each time a cell expires, it sends out a message to the immune system. If the death is caused by trauma, such as inflammation, the message tends to stimulate white blood cells to become aggressive. But if the cell dies a programmed death at the end of its natural life cycle, it sends out a calming signal.
In the human body there is a type of cell that dies off profusely, at the order of 200 billion per day: red blood cells. There are as many calming signals transmitted daily to the immune system.
The scientists therefore attached the pancreatic protein targeted by T-cells in type I diabetes to red blood cells. “Our idea was that by associating the protein under attack to a soothing event, like the programmed death of red blood cells, we would reduce the intensity of the immune response,” explains Jeffrey Hubbell, co-author of the study. To do this, the researchers opted for state-of-the-art bioengineering: the protein, equipped, with a hook of molecular size, is able to attach itself to red blood cells. Billions of these were manufactured and then simply injected into the body.
Eradication of diabetes symptoms
As these billions of red blood cells died their programmed death, they released two signals: the artificially attached pancreatic protein, and the soothing signal. The association of these two elements retrained the T lymphocytes to stop attacking the pancreatic cells – like Pavlov’s dog who associates the ringing of a bell with a good or bad omen. “It was a total success. We were able to completely eliminate the immune response in type I diabetes in mice,” explains Hubbell.
Minimizing risks and side effects
Co-author Stephan Kontos adds that the great advantage of this approach is its extreme precision. “Our method carries very little risk and should not introduce significant side effects, in the sense that we are not targeting the entire immune system, but just the specific kind of T-cells involved in the disease.”
The scientists are planning to conduct clinical trials in 2014 at the earliest. Instead of directly testing the treatment on disease, their initial tests will aim to counteract the undesired immune response to a drug known for its effectiveness against gout. “We chose to begin with this application before we tackled diabetes or multiple sclerosis, since we know that we can control and understand all of the parameters,” explains Hubbell.
Currently, the researchers are also testing the potential of this method in treating multiple sclerosis. In this disease, T-cells destroy myelin cells which form a protective sheath around nerve fibers. They are also studying the potential of their method with another kind of white blood cell, B-lymphocytes, involved in many other autoimmune diseases.
The Immune System and Multiple Sclerosis
In a healthy body, nerve fibers (also referred to as “axons“) have a protective, fatty-rich protein covering known as myelin. This covering insulates the nerve fibers, similar to the insulating rubber covering of an electric wire. Myelin allows for the smooth and uninterrupted flow of nerve impulses, which in turn, enables the body to send vital instructions from the brain to the different parts of the body.
With multiple sclerosis (MS), the body’s own system of defense, known as the immune system, malfunctions. It sends disease-fighting cells into the central nervous system (CNS) that may destroy the body’s own myelin. This occurs because the immune system is incorrectly identifying the myelin in the CNS as a foreign body. When the body’s own immune system attacks its own tissue, this is referred to as an “autoimmune disease,” and MS is believed to fall into this category. Examples of other autoimmune diseases include lupus and rheumatoid arthritis.
These renderings of the inside of a blood vessel show normal red blood cells, along with immune-system cells that are designed to fight infection and disease. With ms, these cells of the immune system are thought to become misdirected and attack the body’s own tissues – in this case, the nerves of the cns. In order to reach the cns, these immune-system cells must cross the blood-brain barrier – traveling through the blood vessel wall and into the brain and spinal cord.
Lymphocytes are a type of white blood cell and play a strong role in the body’s defense system. Another type of white blood cell is the macrophage, and this works to ingest and destroy foreign substances.
White blood cells circulate in the blood and are produced when the immune system perceives a foreign body and instructs the cells to eliminate it, thereby “protecting” the body. In order to reach the nerves within the CNS, the immune system cells and molecules must cross a protective barrier that surrounds the blood vessels. Known as the blood-brain barrier (BBB), this layer of cells is designed to prevent damaging cells and other substances in the blood (including those that could cause disease) from entering the brain, optic nerves, and spinal cord of the CNS.
With MS, damaging immune-system cells are able to break through the BBB and enter the CNS, where they begin their attack on the myelin. Once the damaging cells enter the CNS, macrophages and other lymphocytes begin their attack on the myelin. This creates inflammation along the nerves where the myelin is being damaged. Areas of activity are known as lesions (or plaques). Lesions vary in activity levels, ranging from very active (acute), to chronic, to inactive.
Remyelination is believed to occur in relapsing-remitting MS (RRMS) when a symptom flare-up subsides and goes into remission. The return of function is thought to result from not only myelin repair, but reduced inflammation as well. Eventually, the axon becomes exposed and damaged, and the myelin may no longer be repaired. With primary-progressive MS (PPMS) and other forms of progressive MS, the oligodendrocytes are unable to repair the myelin, and therefore symptoms do not remit.
Shown above is a 3-D rendering of nerve cells; the axon and protective myelin can easily be seen extending out to the side of the cell body.
Often, myelin that is damaged may be restored through a process called “remyelination,” particularly early in the disease. Oligodendrocytes are cells that produce and maintain myelin. Over time, however, oligodendrocytes may be lost and unable to repair the damaged myelin.
Areas of damaged myelin become scarred and can no longer fully insulate the nerve – leaving unprotected areas, where the flow of nerve impulses is interrupted. This interruption in the communication between the brain and other parts of the body results in the symptoms experienced by individuals with MS.
Read The MS Process and Targets for Treatment.