Autoantibodies are proteins produced by the immune system that mistakenly target and attack the body's own cells and tissues. Normally, the immune system protects the body from foreign invaders like bacteria and viruses. However, in some cases, it can become confused and produce autoantibodies, leading to autoimmune diseases. These autoantibodies can be found in various conditions, such as rheumatoid arthritis, lupus, and type 1 diabetes. Their presence can help doctors diagnose these diseases and monitor their progression. Understanding autoantibodies is crucial for developing effective treatments and managing autoimmune disorders.