What causes autoimmune diseases?

The immune system protects the body against harmful substances such as viruses, bacteria, cancer cells and toxins by producing antibodies that destroy antigens contained within these substances. Autoimmune disorders result when the immune system does not differentiate between the body’s healthy tissues and potentially harmful antigens. When this happens, the body develops an autoimmunity against its own healthy cells and tissues and sets off a reaction that destroys them. 

Researchers have still not determined the exact cause of autoimmune disorders but studies indicate that they most likely result from interactions between genetic and environmental factors. 

Genetic predisposition, being a female of child-bearing age, impaired treg response, infections are some of the known risk factors that increase a person’s chances of developing an immune disease.