DEFINITIONS AND TYPES OF AUTOIMMUNITY
AUTOIMMUNITY VERSUS AUTOIMMUNE DISEASE
The classical studies of Paul Ehrlich in the early twentieth century laid the foundation for our current notions of the concept of autoimmunity. Ehrlich used the term autoimmunity to signify an immune response against self and introduced the phrase horror autotoxicus, suggesting that there are mechanisms to protect against autoimmunity. Over the years, autoimmunity has been recognized as not uncommon and not necessarily detrimental. Thus, an important distinction must be drawn between autoimmunity, which may be asymptomatic, and autoimmune disease, which occurs when autoimmunity leads to an inflammatory response, resulting in tissue injury. An autoimmune response does not necessarily imply the existence of autoimmune disease.