What Is Immunogenicity?

Immunogenicity is the measure of any properties possessed by a substance which allow the substance to trigger an immune system response in either a human or animal life form. Substances that trigger a response from a biological form’s immune system might be either an antigen or an epitope. Normally, immunogenicity is measured for foods, liquids and pharmaceuticals that are engineered to produce very specific immune system responses.

Foreign substances might be designed or engineered for immunogenicity, such as certain drugs. These substances can rely on an antigen, or a molecule that triggers an organism’s production of antibodies which are used to fight off infections. More specifically, antigens use epitopes, which are the components of any antigen that an organism’s immune system recognizes and responds to, eliciting a response from an immune system.

A drug’s immunogenicity affects how well the drug benefits an organism. When a drug is not very immunogenic, it might not be potent enough to protect the body against a present or possible infection. Several factors can affect a drug’s potency, such as how the drug is administered to the organism, the structure and robustness of individual organisms’ immune systems and even the size of the molecules that compose the drug.

The effects of a substance’s immunogenicity are directly affected by an organism’s paratopes. The paratopes are the components of antibodies that recognize an epitope. Normally, paratopes are only found in certain components of an organism’s immune system, such as in T cells, antibodies, and B cells. The immunogenic response triggered in these cells enable them to effective fight off infections of various types, protecting the organism’s overall health.

Proteins tend to possess a higher level of immunogenicity than most other substances. Polysaccharides also can produce an immune system response in organisms, although in general they do not possess the same levels of immunogenicity as proteins. This means that fats and nucleic acids used in medications must be bound to a protein or a polysaccharide so they can produce an immune response in an organism.

Researchers have developed methodologies for scoring different protein structures’ immunogenicity. The different scores are divided into classes, which express how likely different types of protein structures will evoke an immune system response. Pharmaceutical companies, researchers and others can analyze a drug’s different protein structures, and based on the classes of those structures as well as the density of the structures in the drug, make educated guesses about the potency of the drug before testing it on live organisms.