Gamma globulin G, more precisely known as Immunoglobulin G (IgG), is the most abundant type of antibody in the human body, accounting for approximately 75% of all serum immunoglobulins. As a key component of the gamma globulin fraction of blood proteins, IgG plays a critical role in the immune system's defense against bacterial and viral infections. It is produced by plasma cells and circulates in the blood and extracellular fluid, where it recognizes and binds to specific antigens, marking them for destruction by other immune cells. IgG is also the only antibody class that can cross the placenta, providing passive immunity to newborns. Clinically, IgG levels are often measured to assess immune function or to diagnose conditions such as immunodeficiencies, chronic infections, or autoimmune diseases.
Gammaglobulin G
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