Your white blood cells make antibodies to help fight pathogens in your body. These antibodies are an essential part of your immune system and help keep you from getting sick. Each antibody your white blood cells produce is designed to attack a specific kind of illness, also known as an antigen. An antigen is anything that can get you sick, including bacteria, viruses, and toxins.
The antibodies are designed to bind to and attack a specific type of antigen. When your antibodies sense an antigen in your system, they bind to it and stop its movement through cell walls so the invader can be removed, preventing it from infecting you. If the antigen is a toxin, the act of binding typically cancels the toxin’s chemical action.