Gamma globulin M, more accurately referred to as immunoglobulin M (IgM), is the first type of antibody produced by the immune system in response to an infection. It is a part of the gamma globulin fraction of serum proteins and plays a critical role in the body’s initial defense against pathogens. IgM is primarily found in the blood and lymphatic fluid, and because of its large size, it is especially effective at forming complexes with antigens and activating the complement system. Elevated levels of IgM can indicate recent or acute infections, autoimmune disorders, or certain types of blood cancers, while low levels may suggest immune deficiencies. As the immune response progresses, IgM is typically replaced by other immunoglobulins such as IgG, which provide longer-lasting immunity.
Gammaglobulin M
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