Immunoglobulin G (IgG) and IgG idiotypes (IgG)

Self Immunoglobulin G (IgG) and IgG idiotypes are therapeutic targets primarily addressed in the management of autoimmune disorders and B-cell malignancies. IgG is the dominant antibody isotype in human circulation, responsible for neutralizing pathogens and mediating effector functions like complement activation (Gable et al., 2020). In autoimmune diseases, "self-IgG" refers to pathogenic autoantibodies that target host tissues; these are therapeutically managed by inhibiting the neonatal Fc receptor (FcRn), which normally recycles IgG to extend its half-life (Ulrichts et al., 2018). The "idiotype" represents the unique antigenic determinants in the variable region of an IgG molecule, serving as a clonal marker for B-cells. In oncology, the idiotype of the B-cell receptor on malignant cells is targeted via personalized vaccines to induce a specific anti-tumor immune response (Bendandi, 2009). Additionally, intravenous immunoglobulin (IVIG) therapy utilizes a pool of donor IgG containing anti-idiotypic antibodies to neutralize a patient's own pathogenic self-IgG (Kazatchkine & Kaveri, 2001). This dual-target approach allows for both the broad reduction of harmful antibodies and the highly specific targeting of malignant B-cell clones.

Other names

Endogenous IgGAutoantibodiesB-cell receptor idiotypeSurface immunoglobulin idiotypeSelf-antigenic IgG

Neonatal Fc receptor (FcRn) antagonism to reduce circulating IgG levels; active immunization against tumor-specific idiotypes; anti-idiotypic neutralization of autoantibodies.