Antibodies, also known as immunoglobulins, are proteins produced by the immune system to fight off infections. They are found in various locations throughout the body, including:
- Bloodstream: Antibodies circulate in the bloodstream, ready to bind to and neutralize invading pathogens like bacteria and viruses.
- Lymph system: The lymphatic system is a network of vessels and tissues that help filter waste and fight infections. Antibodies are present in lymph fluid, allowing them to reach different parts of the body.
- Mucosal surfaces: Antibodies, particularly IgA, are secreted onto mucosal surfaces like the gut, respiratory tract, and reproductive tract, providing the first line of defense against pathogens entering the body. They are also found in saliva, tears, and breast milk.
In addition to these primary locations, antibodies can also be found in:
- Tissue fluids: Antibodies can be found in fluids surrounding tissues, such as cerebrospinal fluid and synovial fluid.
- Organs: Certain organs, like the spleen and lymph nodes, house immune cells that produce and store antibodies.
Antibodies play a crucial role in protecting the body from disease. They are highly specific, meaning they only bind to particular targets, such as viral proteins or bacterial toxins. This specificity allows antibodies to target specific pathogens without harming healthy cells.
