Human immunoglobulin (Ig)

Human immunoglobulins, or antibodies, are critical components of the adaptive immune system produced by plasma cells. They consist of two heavy chains and two light chains, forming a Y-shaped structure with variable regions for antigen binding and a constant (Fc) region that mediates effector functions through protein-protein interfaces with Fc receptors and complement proteins (Janeway et al., 2001, Immunobiology). In therapeutic contexts, the protein-protein interfaces of immunoglobulins are targeted to modulate immune responses; for instance, blocking the IgE-FcεRI interface treats allergic asthma, while inhibiting the IgG-FcRn interface promotes the clearance of harmful autoantibodies in diseases like myasthenia gravis (Gable et al., 2020, Nature Reviews Drug Discovery). The term "Human immunoglobulin at protein–protein interface" likely refers to these specific interaction sites, such as the CH2-CH3 domain interface used for FcRn binding, which are pivotal for regulating antibody half-life and effector activity (Pyzik et al., 2019, Frontiers in Immunology).

Other names

AntibodyGamma globulinImmune globulinImmunoglobulin GImmunoglobulin EFc region

Drugs targeting human immunoglobulins typically work by neutralizing specific isotypes (e.g., anti-IgE) to prevent allergic signaling or by targeting the neonatal Fc receptor (FcRn) to accelerate the degradation of pathogenic IgG autoantibodies.