What is igm?

IgM, also known as Immunoglobulin M, is a type of antibody produced by the immune system in response to an initial exposure to an antigen (a foreign substance such as a virus or bacteria). IgM is the first antibody to be produced during an infection and is typically found in high levels in the bloodstream during the early stages of the immune response.

IgM antibodies are large molecules and are composed of five units or pentamers, which give them a unique circular shape. They play a crucial role in activating the complement system, which helps to clear pathogens from the body. IgM also acts as a signal to other immune cells to fight the infection and is involved in neutralizing toxins and viruses.

IgM levels are used in medical testing to diagnose certain infections such as viral infections like hepatitis B and C, and bacterial infections like Legionella and Rocky Mountain spotted fever. Low IgM levels can be associated with primary immunodeficiencies, while high levels of IgM may indicate an autoimmune disease or chronic infection.