IgM Human
Human plasma.
Sterile Filtered solution.
Greater than 95.0%.
Description
Human Immunoglobulin-M produced in human plasma having a molecular mass of 950kDa.
Product Specs
The primary antibody that the immune system generates upon encountering an antigen for the first time is immunoglobulin M (IgM). This antibody is produced by B cells. IgM antibodies are present in both the blood and lymphatic systems, making them the third most prevalent type of immunoglobulin in serum. Immunoglobulin M (IgM) occurs in two forms, primarily as a pentamer with a molecular weight of 970 kDa and less commonly as a hexamer. The pentameric form of IgM possesses ten antigen-binding sites, with each monomer containing two. However, due to steric hindrance in the hexameric complex, the J chain is absent in the hexameric form of IgM. IgM antibodies are an early indicator of infection and typically reappear in lower concentrations upon subsequent exposures to the same antigen. Unlike IgG antibodies, IgM antibodies are unable to cross the placenta in humans. These characteristics of IgM make it a valuable tool for the diagnosis of infectious diseases.
Human Immunoglobulin-M is a protein found in human plasma. It has a molecular mass of 950kDa.
A solution that has been sterilized by filtration.
This solution of IgM (1.98mg/ml) is buffered to a pH of 8.0 with 50mM TRIS and also contains 0.2M NaCl and 0.05% NaN3.
If the entire vial will be used within 2-4 weeks, it can be stored at 4°C. For longer storage periods, it should be frozen at -20°C.
It is recommended to add a carrier protein (0.1% HSA or BSA) for long-term storage.
Repeated freezing and thawing of the product should be avoided.
The purity of this product is greater than 95.0%.
Human Immunoglobulin-M has undergone testing and been found to be negative for antibodies against HIV-1, HIV-2, anti-HBc, HCV, and HBSAG.
Human plasma.
Product Science Overview
Immunoglobulin M (IgM) is a crucial component of the immune system, serving as the first line of defense against pathogens. It is the largest antibody and is characterized by its unique structure and functions. IgM is present in all vertebrates and plays a vital role in both the innate and adaptive immune responses.
The discovery of IgM dates back to 1937 when an antibody larger than the typical γ-globulin was observed in horses hyper-immunized with pneumococcus polysaccharide . This antibody, initially referred to as γ-macroglobulin, was later termed IgM, with “M” standing for “macro” due to its large size . The structural analysis of IgM was challenging due to its heterogeneity, but significant progress was made with the discovery of homogeneous IgM in multiple myeloma patients and the development of methods to induce immunoglobulin-producing tumors in mice .
IgM is composed of light chains (λ or κ) and heavy chains (μ). The μ heavy chain includes a variable domain (VH) and four constant region domains (Cμ1, Cμ2, Cμ3, Cμ4), along with a tailpiece . The pentameric form of IgM, which is predominant in serum, contains a joining chain (J chain) that facilitates its transport across mucosal epithelia . This structure allows IgM to bind effectively to viral surface proteins and tolerate mutations in viral targets .
IgM is the first antibody produced in response to an antigen and is crucial for early immune responses . It exists in two forms: a pentamer in serum and a membrane-bound monomer on B lymphocytes . The pentameric form is highly effective in binding to pathogens and activating the complement system, which enhances the ability of antibodies and phagocytic cells to clear microbes and damaged cells .
IgM also plays a role in diagnosing infections, as its presence indicates a recent exposure to a pathogen . Additionally, long-lived IgM plasma cells, predominantly residing in the spleen, have been observed to provide protection against lethal infections, such as influenza, in murine models .
IgM’s role in the immune system extends beyond its initial response to pathogens. It has been shown to carry specific host proteins, such as the apoptosis inhibitor of macrophages (AIM), which promotes the removal of dead-cell debris, cancer cells, or pathogens . This function highlights IgM’s potential in therapeutic applications, including vaccine strategies aimed at preventing virus acquisition .
