The most common immunoglobulin (antibody) in humans is IgG.
Understanding IgG: The Predominant Antibody
Based on the provided reference, IgG is the most abundant immunoglobulin found in human serum. It constitutes a significant portion of the total antibodies in the body, accounting for 70% to 75% of all immunoglobulins. This high prevalence makes IgG a crucial player in the human immune system.
Key Characteristics and Functions of IgG
IgG antibodies are vital for long-term immunity and defense against various pathogens. Their functions include:
- Dominance in Secondary Immune Response: IgG is the primary antibody involved in the secondary immune response, which is the body's rapid and stronger reaction upon subsequent exposure to an antigen it has previously encountered.
- Elimination of Foreign Invaders: The main role of IgG is to neutralize and eliminate harmful foreign substances. This includes a wide range of invaders such as:
- Viruses
- Bacteria
- Toxic substances (toxins)
- Passing through the Placenta: IgG is the only immunoglobulin that can cross the placenta, providing passive immunity from mother to fetus during pregnancy.
In summary, IgG's high concentration and broad range of functions make it the central component of the body's adaptive immune response, offering protection against numerous threats encountered throughout life.
