Your own cells were created with certain "recognition" proteins on their cell membrane, which tells your immune system to ignore them when encountered. When this process fails, we see many "auto-immune" diseases like multiple sclerosis. It is also recently thought that Asthma and Diabetes may have some "auto-immune" components which tend to destroy pancreatic islet cells or epithelial cells in the bronchioles.
1. Your immune system can recognize cells based on the proteins present on the surface of cells. Viruses, bacteria, and other foreign cells are recognized as being different from your own cells and are attacked by your immune system.
It means your immune system begins to attack your body's own healthy cells and tissues, when it is only supposed to attack viruses and bacteria that might cause you harm. Check out auto immunity
The immune system will target the body's own cells
the body's immune system accidentally misidentifies markers on the body's own nerve cells as foreign. The immune system then begins to produce cells that attack and injure or destroy either the nerve cells
1. Your immune system can recognize cells based on the proteins present on the surface of cells. Viruses, bacteria, and other foreign cells are recognized as being different from your own cells and are attacked by your immune system.
When your cells attack each other, it is known as autoimmunity. This occurs when the immune system mistakenly targets and damages the body's own cells and tissues, leading to various autoimmune diseases like rheumatoid arthritis and lupus.
In a healthy person, white blood cells only attack invading germs, and would not attack the person's own internal organs. However, there are autoimmune diseases, which cause the immune system to become confused and to attack the wrong targets.
An autoimmune disease is caused by the immune system attacking you instead of threats and diseases coming from outside you. In autoimmune diseases, the body makes a mistake and attacks its own tissues.a condition that causes the body's own immune system to wrongly identify cells as foreign and attack them.
Typically, healthy body cells do not actively kill other healthy body cells. This process is usually regulated by the immune system to eliminate damaged or infected cells. However, in certain conditions such as autoimmune diseases, the immune system may mistakenly attack healthy cells.
Cancer is somewhat confusing to the immune system since it is an aberrant form of the body's own cells which the immune system is not supposed to attack. Sometimes the immune system can detect that the cancer cell is not a normal part of the body, and therefore it will destroy the cancer, but quite often the immune system cannot detect the abnormality of the cancer cell and will ignore it. That is precisely why cancer is so dangerous.
At a basic level here's how it works: The surfaces of our cells have protein "markers" embedded in them, each person's markers are unique. If the immune system doesn't recognize the markers on a cell, it will attack it as being foreign. This usually works pretty well asa defense systems go, however, there are times (autoimmune diseases like Grave's disease, MS and rheumitoid arthritis) when the system attacks the body's own cells anyway or other diseases (HIV, etc) where the immune system doesn't recognize foreign cells, so doesn't attack.
The body uses surface markers called antigens to identify its own cells. These antigens are like a cellular ID card that tells the immune system that the cell is part of the body and not a foreign invader. Cells that display these self-identifying antigens are generally spared from attack by the immune system.