What are some factors that might contribute to the development of an autoimmune disease?

Self-tolerance of the immune system starts after birth and goes on through the lifetime. However,when the immune system loses its self-tolerance, the innate malfunctioning leads to its inability to distinguish between self-antigens from its non-self antigens.

Events, such as trauma or infection, can lead to the tissues getting exposed to the lymphocytes or the immune system, which that can lead to autoimmune disease.

Antibodies to certain bacterial or viral antigens can cross-react with the endogenous substances leading to some autoimmune diseases.

In some autoimmune diseases, generalized breakdown of the immune system can cause the generation of antibodies to several endogenous substances, such as DNA and phospholipids.