IgM | Immunoglobulin M Class

Author: Misha Rahman, Ph.D.

Human IgM (immunoglobulin M)  is expressed on the surface of immature and mature B cells as monomers. IgM is the third most abundant human immunoglobulin.

IgM is also the first human immunoglobulin to be made by a fetus and virgin B cells which are challenged with antigen. IgM is a strong complement activator and agglutinator due to its pentameric structure and binds fragment crystallization (Fc) receptors.

IgM
Immunoglobulin M IgM

Heavy chain

μ

Light chain

κ or λ

Molecular formula

2κ2)5 or (μ2λ2)5

Valency

10

Structure

Pentamer

Abundance in serum (in relation to total immunoglobulins present)

6%

Carbohydrate content

12%

Concentration in serum

0.5 - 2.0 mg/ml

IgM subclasses

None

Heavy chain MW (kDa)

70

Light chain MW (kDa)

23

Total MW (kDa)

970

Distribution

Mainly intravascular

Function

Primary response antibody


Antibodies for Human IgM Isotype

Bio-Rad offers a range of human immunoglobulin antibodies for the IgM isotype. In addition to Human, we also offer IgM antibodies for the mouse specificity. Below are a few of our products but feel free to search for a specific product using our search bar at the top of the page.

IgM (Immunoglobulin M) Antibodies for Human and Mouse

    DescriptionSpecificityTargetFormatHostIsotypeClone Applications Citations Product Type Code