Immunoglobulin

An immunoglobulin, also known as an antibody, is a large, Y-shaped protein produced by plasma cells (a type of white blood cell) that is used by the immune system to identify and neutralize foreign objects like bacteria and viruses. Immunoglobulins recognize unique parts of the foreign object, called antigens. This triggers an immune response and the destruction or deactivation of the threat. There are five main classes of immunoglobulins (IgG, IgM, IgA, IgE, and IgD), each with different functions and locations within the body, playing critical roles in various immune defenses.

Immunoglobulin meaning with examples

• The doctor ran blood tests to measure the patient's immunoglobulin levels to assess their immune response to the suspected infection. The elevated immunoglobulin indicated the body was actively fighting the illness. Further analysis revealed the specific class of immunoglobulin responsible, aiding diagnosis.
• Vaccines work by introducing a weakened or inactive form of a pathogen, prompting the body to produce specific immunoglobulins. These immunoglobulins remain in the body to provide protection, allowing the immune system to quickly neutralize the real pathogen in the future.
• During an allergic reaction, the body produces immunoglobulin E (IgE) in response to allergens like pollen or peanuts. This IgE triggers the release of histamine and other inflammatory mediators, leading to symptoms like hives and swelling. This is then treated with antihistamines.
• Immunoglobulin G (IgG) is the most abundant type of antibody in the blood and the main antibody of the secondary immune response. It protects the body from bacteria, viruses, and toxins, also providing passive immunity to the fetus across the placenta.
• In some autoimmune diseases, the body's immune system mistakenly attacks its own tissues, producing autoantibodies, which are a form of immunoglobulin, that targets healthy cells. This causes chronic inflammation and tissue damage.