Anti- Human IgG3

Immunoglobulin (Ig) G (IgG) is the predominant of five classes of Ig (IgG, IgA, IgM, IgE, and IgD). Igs differ in heavy chain structure and effector function. IgG1, the largest IgG subclass, represents ~ 60% of IgG and has a half-life of 21 days.
In normal adults, IgG3 represents ~ 4% of serum IgG. IgG3 activates complement more readily than other IgG subclasses, has high affinity for Fc receptors on phagocytes (FcγR), crosses the placenta less readily than IgG1 and IgG4 but more so than IgG2, and has an overall half-life of ~ 7 days. Some adults with frequent or severe respiratory tract infection have subnormal IgG3 (< 2 SD below respective means)