globulinen

Globulins are a broad group of globular proteins found in blood serum and other body fluids, contributing to the majority of plasma proteins aside from albumin. They are typically classified by electrophoretic mobility into four major fractions: alpha-1, alpha-2, beta, and gamma globulins. Immunoglobulins, or antibodies, are contained within the gamma globulin fraction and are produced by plasma cells in response to antigens. Other globulins include transport and enzyme-related proteins such as transferrin, haptoglobin, and ceruloplasmin, which reside in the alpha- or beta fractions.

Synthesis and distribution vary among globulins. Many are produced by the liver, while immunoglobulins are produced by B lymphocytes and plasma cells. Globulins undertake diverse roles, including transport of metals and lipids, binding of free hemoglobin by haptoglobin, copper transport by ceruloplasmin, and defense against pathogens through antibodies. They also participate in the acute-phase response during inflammation and infection.

Clinical relevance centers on the measurement of globulin levels as part of total serum protein analysis. Hyperglobulinemia, an increased globulin fraction, can arise from chronic inflammation, autoimmune disease, liver disease, or monoclonal gammopathy. Hypoglobulinemia, a decreased globulin fraction, may result from protein loss, malnutrition, or severe illness. Electrophoresis patterns of globulin fractions aid in diagnosing immune deficiencies, chronic infections, or hematologic disorders. The term globulin reflects their globular protein structure and diverse functional roles.