IgG | Immunoglobulin G Class

Author: Misha Rahman, Ph.D.

Human IgG (immunoglobulin G) is expressed on the surface of mature B cells and is the most prevalent Ig in serum and the major Ig in extravascular spaces. IgG1, IgG2 and IgG3 are complement activators, with IgG3 being the strongest.

Human immunoglobulin subclasses IgG1 and IgG3 tend to strongly bind fragment crystallization (Fc) receptors, whereas subclasses IgG2 and IgG4 bind weakly. IgG is also the only human immunoglobulin to pass from mother to fetus to transfer immunity.

It should be noted, the human immunoglobulin subclass IgG2 does cross the placenta, but it does so weakly.

IgG Immunoglobulin Class G: IgG

Heavy chain

γ

Light chain

κ or λ

Molecular formula

γ2κ2 or γ2λ2

Valency

2

Structure

Monomer

Abundance in serum (in relation to total immunoglobulins present)

80%

Carbohydrate content

3%

Concentration in serum

10 - 16 mg/ml

IgG subclasses

IgG1

IgG2

IgG3

IgG4

Heavy chain subclasses

γ1

γ2

γ3

γ4

Heavy chain MW (kDa)

50

50

60

50

Light chain MW (kDa)

23

23

23

23

Total MW (kDa)

150

150

170

150

Distribution

Intravascular and extravascular

Function

Secondary response antibody


Antibodies for Human IgG Isotype

Bio-Rad offers a range of human immunoglobulin antibodies for the IgG isotype. In addition to human, we also offer IgG antibodies for the mouse specificity.

IgG (Immunoglobulin G) Antibodies for Human and Mouse

    DescriptionSpecificityTargetFormatHostIsotypeClone Applications Citations Product Type Code