- An antibody is a protein produced by the body’s immune system when it detects harmful substances, called antigens. Examples of antigens include microorganisms (bacteria, fungi, parasites, and viruses) and chemicals.
- Antibodies may be produced when the immune system mistakenly considers healthy tissue a harmful substance. This is called an autoimmune disorder.
- Each type of antibody is unique and defends the body against one specific type of antigen.
Source: NLM_NIH, 27 OCT 2014, www.nlm.nih.gov/medlineplus/ency/article/002223.htm