Excerpt:

Autoimmunity refers to an inappropriate immune response against self-components of the host that results in pathological conditions. Autoimmune diseases are characterized by an activation of autoreactive T and B cells, are associated in some cases with the production of pathogenic autoantibodies against self-molecules, culminating in inflammation and tissue damage. The reasons for the breakdown of tolerance mechanisms leading to autoimmunity are not clearly known. However, a combination of genetic, immunological, and environmental factors plays a critical role in the pathogenesis of autoimmunity