About ITP

Causes

Causes of Autoimmune Diseases

No one really knows what causes ITP. Here are some general theories on the causes of autoimmune diseases. Although these are presented as three theories, they can be viewed as pieces of a larger puzzle.

Microbial Trigger Theory

Scientists have discovered that we have immune cells which, when activated, can target the body’s own molecules. Researchers at the National Institute of Allergy and Infectious Diseases, Yale University, and Duke Medical Center, among others, have found these cells can be activated by bacteria, at least in mice.

When it is fighting a reaction, the body produces a compound called interleukin-12 during it’s normal immune response. Interleukin-12 then creates many other immune compounds specific to a particular microbe. Researchers think this flurry of activity may activate any dormant self-reactive cells that may be near the infection. (If the self-reactive cell is for platelets, you get ITP) This also suggests that interleukin-12 inhibitors may aid people with auto-immune disorders.

(Summarized from "Microbial Trigger for Autoimmunity?" Science News, 6/21/97)

Molecular Mimicry Theory

This theory suggests that autoimmune diseases are caused when a person’s immune response gets confused between it’s own cells and invading virus and bacteria if the invaders are similar to the host cells.

When a virus invades our body, special cells chop it up into thousands of fragments and put some of them in a type of pocket for the immune system to disable. A person’s genes determine which of the invader fragments go in the pocket. T cells latch on to the fragments in the pocket and send signals to destroy all of the tissues that have that type of fragment.

The problem comes when some part of the body has the same amino acid sequence on its surface as the invader fragment. When this happens T cells attack the ‘good’ cells with the twin fragments as well as those with the pocketed viral fragment. Another study suggests that the good cells might not need the same amino acids sequence. Perhaps just having another similar property, such as a negative charge, can create the same confusion. This means that a larger number of proteins with different amino acid sequences can stimulate the same T-cell, setting off an auto-immune disease.

The thymus contains a master list of the body’s most abundant proteins. When T cells are born, they are compared to the master list. Those that recognize self-proteins are killed off. There are, however, some proteins that are not on the master list. So T cells that recognize these proteins are not destroyed. Other immune factors suppress these self-reactive T cells. When that control is lost, an auto-immune disease can begin.

According to the research scientists, the disease process involves many more steps. The bad luck may unfold over several years and require multiple infections and a genetic predisposition to activate.

(Summarized from "Virus’s Similarity to Body’s Proteins May Explain Autoimmune Diseases"12/31/96, New York Times)

Free Radical Damage

In this theory, the DNA in our cells can be altered or destroyed by reactive substances in our bodies. When the destroyed DNA is a part of the immune control function, it can result in a specific autoimmune disease.

Oxygen outside our bodies can cause iron to rust and is necessary for paper to burn. On the inside, it can be equally destructive. Free radicals are particles that have an unstable molecular structure. They act as scavengers in the body and rob electrons from other molecules to increase their stability. The particles that are robbed don’t function as they should and can be toxic. There are several types of free radicals. Some of the most common have an oxygen base. For people with ITP, imagine that our platelets are cooked by it.

Free radicals build over time. They are a natural byproduct of our metabolism and immune system functions. They are a natural component of aging. Their production is hastened by stress, pollution, fertilizers, pesticides, prescription drugs, alcohol, electromagnetic radiation, etc.

Our bodies have built in controls for free radicals and ways of changing them into neutral substances. These detoxification mechanisms require specific enzymes to make them function well. If our bodies do not have the vitamins and minerals to make up the enzymes, or if the detoxification mechanism is damaged, perhaps by free radicals, the result is a surplus of free radicals and other toxic substances. This can also happen if our life style and environment results in our having too many toxins for even a good working system to neutralize.

The excess free radicals and other noxious byproducts of a failed detox process roam our bodies and attack our weakest links. These weak links may be due to genetics. They may be other parts of our immune system that happen to be nearby. Depending on the DNA attacked, the electron grabbing can cause an auto-immune disease.

Theoretically, if a surplus of free radicals is the cause of the disease, reducing the amount of things that promote their production (ex. stress) , ingesting substances that reduce the number of free radicals (ex. Vitamin C) and making sure our detoxification mechanisms have sufficient nutrients (eating well) may be part of the cure.

(Summarized from Sharma, Hari, M.D. Freedom from Disease, Toronto, Ontario:Veda Publishing, 1993, Rogers, Sherry A, M.D., Tired or Toxic? A Blueprint for Health. Syracuse, NY: Prestige Publishing, 1990, and a conversation with a research scientist at Rutgers University)