ANSWER is Antigen.Any substance that causes your immune system to produce antibodies against it is known as an antigen.This indicates that your immune system has misidentified the substance and is attempting to combat it.Material from the environment, such as chemicals, bacteria, viruses, or pollen, may act as an antigen. Antigens can also develop within the body.Proteins, peptides (amino acid chains), and polysaccharides (chains of monosaccharides/simple sugars) are all antigens, but lipids and nucleic acids only become antigens when they are MIXED with proteins and polysaccharides.Vaccines are IMMUNOGENIC antigens that are administered to a recipient with the aim of inducing the adaptive immune system's memory mechanism of antigens of the pathogen invading the recipient.Antibodies are large, Y-shaped proteins that the immune system uses to recognize and neutralize foreign OBJECTS like bacteria and viruses.Enzymes are biological catalysts that are proteins (biocatalysts).Hormones are signaling molecules that are transported to distant organs in multicellular organisms to control physiology and/or BEHAVIOR.