Immunogenicity

Immunogenicity, also called immunogenicity, the ability of a substance to elicit an immune response referred to as the immune system response in the animal or human body. Substances with a immunogenicity are called immunogens. Immunogenicity is not a fixed quantity, but depends on the immune system of the organism in which the substance in question is located. It is therefore different both individually and depending on the degree of the phylogenetic relationship between species of animal from which the antigen is derived and the species in which it acts as an immunogen.

Factors

A substance that is recognized by the body as an antigen, can elicit an immune response via different mechanisms and therefore have an immunogenic potential. Protein or peptide components play a central role in the adaptive immune system mediated via the immunogenicity of a substance. These are only after enzymatic cleavage in the lysosomes of the cell surface antigen recognized cells such as B lymphocytes, macrophages or dendritic cells, presented and recognized by T lymphocytes. The immunogenicity of lipopolysaccharide, bacterial DNA and double-stranded viral RNA is due to the involvement of the innate immune system and in most cases, activation of Toll-like receptors.

The degree of immunogenicity of a substance is dependent upon several factors. These include, in particular body foreignness, molecular size and chemical structure. Other factors such as the type of recording of the immunogen may affect the degree of immunogenicity. How to Solve sub or intracutaneously administered antigens from the strongest immune response during intravenous potential immunogens are widely tolerated.

Body strangeness

An important prerequisite for immunity is the body strangeness. This is caused by self- tolerance of the immune system, detected by the self-antigens and the immune response be suppressed.

Molecular size

Another is the relationship between the molecular size and the immunogenicity of a substance. Substances having a molecular weight of less than about 5,000 daltons are usually not immunogenic.

Chemical structure

Another factor influencing the chemical properties of the molecule, the secondary and tertiary structure require certain features for an immunogenic effect. The relevant portions of the molecule, which are relevant to an immune response are referred to as epitopes. Number and density of such epitopes on a molecule thus determine the degree of immunogenicity. From high immunogenicity are particulate or aggregated proteins, as these are particularly easily absorbed into the antigen-presenting cells.