Description_x000D_ General description_x000D_ There are five immunoglobulin classes in humans. Out of these, immunoglobulin M (IgM) is a high molecular weight protein that has five or six subunits. IgM monomers are made of two heavy chains and two light chains connected by a disulfide bond. Human serum shows low concentration of IgM monomers. It has a high carbohydrate content of about 12%. It is the first immunoglobulin produced by neonates._x000D_ IgM antibodies are present as pentamers in the serum and are produced in response to antigens._x000D_ IgM from human serum is purified from normal human serum by precipitation and gel filtration techniques. The immunoglobulin is determined to be atleast 95% pure by HPLC procedures._x000D_ Application_x000D_ Purified human IgM may be used as a reference antigen, standard, blocking agent, or coating protein in a variety of immunoassays including ELISA, dot immunobinding, Western immunoblotting, immunodiffusion, and immunoelectrophoresis. Other applications include starting materials for the preparation of immunogens and solid phase immunoadsorbents. IgM from human serum was used as standard in ELISA (100 μg/ml) and dot blot assay. Antibody concentration range of 200 μg/ml to 1 mg/ml was used in IgM binding assays._x000D_ IgM from human serum has been used_x000D_ • in ELISA inhibition assay_x000D_ • in immunoblotting_x000D_ • as MW (molecular weight) standards_x000D_ • in IgM binding assay_x000D_ • to confirm the depletion of immunoglobulins_x000D_ Packaging_x000D_ 1, 5 mg in glass bottle_x000D_ 10 mg in serum bottle_x000D_ Biochem/physiol Actions_x000D_ Immunoglobulin M (IgM) acts as an antigen specific part of the B cell antigen receptor on the surface of B lymphocytes that are not stimulated, in its monomeric form. Polymeric IgM molecules also serve as important activators of the classical complement cascade. IgM is essential in agglutination and cytolytic reactions._x000D_ Physical form_x000D_ Solution in 0.05 M Tris-HCl, 0.2 M sodium chloride, pH 8.0, containing 15 mM sodium azide._x000D_ Storage and Stability_x000D_ Store at 2-8 °C. If slight turbidity occurs upon prolonged storage, clarify the solution by centrifugation before use._x000D_ Disclaimer_x000D_ Unless otherwise stated in our catalog or other company documentation accompanying the product(s), our products are intended for research use only and are not to be used for any other purpose, which includes but is not limited to, unauthorized commercial uses, in vitro diagnostic uses, ex vivo or in vivo therapeutic uses or any type of consumption or application to humans or animals.