Immunoglobulin heavy constant mu (IGHM)

Immunoglobulin heavy constant mu is the constant region of the heavy chain defining the **IgM isotype**, one of the main classes of antibody molecules produced by B lymphocytes[1][2][3][5]. It forms part of both membrane-bound and secreted immunoglobulin M. Secreted IgM is the first antibody produced during an immune response, typically as a pentamer, enabling efficient activation of the classical complement pathway and efficient antigen neutralization. Membrane IgM, together with IgD, constitutes the B cell receptor complex on naive B cells, crucial for B cell activation and selection. IGHM deficiency or mutation leads to severe immunodeficiency, manifesting in increased vulnerability to infections. High serum IgM or aberrant IGHM expression can also signal B cell dysfunction, autoimmunity, or lymphoproliferative disorders[1][5].

Other names

Ig mu chain C regionIg mu chain C region BOTIg mu chain C region GALIg mu chain C region OUAGM1MUVHconstant region of heavy chain of IgMimmunoglobulin mu chain

Not therapeutic antibody target; drugs listed (like zinc) are not specific modulators of IGHM but may interact with immune components[2]; Monoclonal antibodies targeting the IgM isotype/IGHM-expressing cells (used sporadically in research or diagnostics, not as direct therapeutics)