IgM
Quick Summary
IgM is a class of immunoglobulins, which are also known as antibodies. It is the first type of antibody produced by B cells as they mature and is commonly found on the surface of B cells as an antigen receptor.1
When secreted, IgM molecules join together to form a large, pentameric structure with ten antigen-binding sites. This structure is highly effective at binding to the outer surfaces of bacteria, causing them to clump together (agglutinate). IgM is crucial in the early stages of the immune response and is efficient at binding complement, a system that helps clear pathogens. It is later replaced by other antibody classes, such as IgG.12
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antibodyAntibody structure and classes…of the word immunoglobulin: IgG, IgM, IgA, IgD, and IgE. The classes of antibody differ not only in their constant region but also in activity. For example, IgG, the most common antibody, is present mostly in the blood and tissue fluids, while IgA is found in the mucous membranes lining…
Read More…of the word immunoglobulin: IgG, IgM, IgA, IgD, and IgE. The classes of antibody differ not only in their constant region but also in activity. For example, IgG, the most common antibody, is present mostly in the blood and tissue fluids, while IgA is found in the mucous membranes lining…
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Because each IgM has five protein units, and thus five potential binding sites, IgM is particularly efficient in precipitating the antigen. After the antigen is precipitated, it can be removed by phagocytes. In addition, antigen binding by IgG or IgM activates a serum protein, called a complement,…
Read MoreBecause each IgM has five protein units, and thus five potential binding sites, IgM is particularly efficient in precipitating the antigen. After the antigen is precipitated, it can be removed by phagocytes. In addition, antigen binding by IgG or IgM activates a serum protein, called a complement,…
Read More 
immune systemIgMIgM is the first class of immunoglobulin made by B cells as they mature, and it is the form most commonly present as the antigen receptor on the B-cell surface. When IgM is secreted from the cells, five of the basic Y-shaped units become…
Read MoreIgM is the first class of immunoglobulin made by B cells as they mature, and it is the form most commonly present as the antigen receptor on the B-cell surface. When IgM is secreted from the cells, five of the basic Y-shaped units become…
Read More
