Immunology

Autoimmune diseases are caused by an overactive immune system.

The immune system incorporates different parts of the body – including certain blood cells, skin, bone marrow and more – that work to keep you healthy. The immune system protects you from infection by detecting and fighting diseases. If infectious agents such as bacteria or viruses get into your body, immune cells usually kill or overwhelm them, removing the infection. This is known as the immune response.