ónæmisglóbúlíni

Ónæmisglóbúlín are proteins produced by specialized white blood cells called B lymphocytes. They are a crucial component of the adaptive immune system, responsible for recognizing and neutralizing foreign invaders such as bacteria, viruses, and other pathogens. These proteins are also known as antibodies.

Each antibody molecule is designed to bind to a specific target, called an antigen, which is typically found on the surface of a pathogen. This binding action can neutralize the pathogen directly, or it can mark the pathogen for destruction by other immune cells. There are five main classes of human antibodies: IgG, IgM, IgA, IgD, and IgE, each with distinct structures and functions.

IgG is the most abundant antibody in the blood and is important for long-term immunity. IgM is typically the first antibody produced during an initial infection. IgA is found in bodily secretions like saliva and breast milk, providing mucosal immunity. IgD is found on the surface of B cells and its exact function is still being researched. IgE is involved in allergic reactions and defense against parasites.

The production of antibodies is a highly specific process. When the immune system encounters a new pathogen, B cells are activated and differentiate into plasma cells, which then secrete large quantities of antibodies specific to that pathogen. This ability to generate a targeted response is a hallmark of the adaptive immune system and is essential for establishing immunological memory, allowing the body to respond more effectively to subsequent encounters with the same pathogen. Therapeutic uses of antibodies, such as in the treatment of autoimmune diseases or cancer, are also an important area of medical research and application.