The antibodies they are proteins produced by certain cells, B lymphocytes, belonging to the body's defense system: the immune system. Present in serum, they bind and neutralize foreign bodies, such as viruses and bacteria, and components of cancer cells.
The antigens they consist of any substance (proteins, polysaccharides, lipids or other chemicals) capable of being specifically recognized by the body's defense system, the immune system. These substances can be of environmental origin or form inside the body.
L'immunity consists of the set of mechanisms involved in the defense of the organism from foreign substances capable of producing infectious and non-infectious diseases.