Dictionary > Opsonization

Opsonization

Definition
noun, plural: opsonizations
The process at which opsonins bind to the surface of the antigen so that the antigen will be readily identified and engulfed by phagocytes for destruction
Supplement
Opsonization refers to the process or molecular mechanism that uses opsonins to make a molecule (e.g. antigen) palatable to the phagocyte. For instance, opsonins (e.g. antibodies) bind to the surface of the bacterial cell. This makes the phagocytes (e.g. NK cells and macrophages) interact strongly with the opsonins coating the bacterial cell. Thus, opsonins serve as marks or tags that designate an antigen or a molecule for ingestion and elimination through phagocytosis.
Phagocytosis is enhanced by opsonization because the opsonins that coat the target molecule results overriding the tendency of the cells to not come close together (Zeta potential). While the Fab region of the antibody binds to the antigen, its Fc region interacts with the Fc receptor on the cell surface of the phagocyte.
Examples of opsonins are antibody molecules such as the IgM that are capable of activating the complement system to increase the susceptibility of antigens to phagocytosis.
Apart from phagocytosis, opsonization can also promote antibody-dependent cell-mediated cytotoxicity. The latter is a process wherein a pathogen is opsonized and coated with IgG antibodies, and this results ultimately in the destruction of the antigen without phagocytosis. Rather, the immune cell that interacts with the IgGs bound to antigen is triggered to release lysis products.
Variant(s):

  • opsonisation (British)

See also:

Related form(s):

  • opsonise (verb, to bind to the surface of antigen to make the latter susceptible to the phagocytosis)

You will also like...

Bryophytes
Bryophytes

Bryophytes (nonvascular plants) are a plant group characterized by lacking vascular tissues. They include the mosses, th..

Protein (illustration)
Protein Variety

The sequence of amino acids determines the type of protein. Protein is synthesized according to the sequence of nucleoti..

Freshwater Ecology
Freshwater Ecology

Freshwater ecology focuses on the relations of aquatic organisms to their freshwater habitats. There are two forms of co..

Body temperature regulation by the hypothalamus
Temperature Regulation in Animals

This tutorial elucidates body temperature regulation. Know the details here to learn how the body sets the body temperat..

Still Water Animals
Still Water Animals

Animals living in aquatic habitats have diversified and evolved through time. They eventually occupy ecological niches a..

Electromagnetic spectrum of a brain
Sleep and Dreams – Neurology

While learning and intelligence are associated with the functions of a conscious mind, sleep and dreams are activities o..

Related Articles...

No related articles found

See all Related Topics