Membrane-bound immunoglobulin M (mIgM) (mIgM)

Membrane-bound immunoglobulin M (mIgM) is the antigen-binding subunit of the B-cell receptor (BCR) complex, primarily expressed on the surface of mature B-lymphocytes [1][2]. It consists of two heavy mu chains and two light chains, which associate with the signaling heterodimer CD79A (Ig-alpha) and CD79B (Ig-beta) to form a functional receptor unit [2][3]. The primary biological role of mIgM is to recognize specific antigens and initiate intracellular signaling pathways, such as the PI3K/Akt and MAPK pathways, which are crucial for B-cell activation, proliferation, and survival [3][4]. In many B-cell malignancies, including chronic lymphocytic leukemia (CLL) and mantle cell lymphoma (MCL), the BCR complex is constitutively active or hypersensitive, driving the growth and survival of malignant cells [4][5]. Consequently, components of the BCR complex and its downstream signaling molecules, such as Bruton's tyrosine kinase (BTK) and Spleen tyrosine kinase (Syk), are major targets for therapeutic intervention [5][6]. While drugs targeting this complex are effective in treating lymphomas and leukemias, they often lead to significant B-cell depletion and hypogammaglobulinemia, increasing patient susceptibility to infections [6][7].

Other names

Surface immunoglobulin MsIgMB-cell receptor complexBCRMembrane IgM

Inhibition of B-cell receptor signaling, induction of apoptosis, and antibody-dependent cellular cytotoxicity (ADCC) leading to B-cell depletion.