Description_x000D_ General description_x000D_ IgG4 (Immunoglobulin G4) is produced by T helper 2 cytokines._x000D_ Specificity_x000D_ Monoclonal Anti-Human IgG4 is specific for the IgG4 subclass and nonreactive with IgG1, IgG2 and IgG3 in an ELISA._x000D_ Application_x000D_ Applications in which this antibody has been used successfully, and the associated peer-reviewed papers, are given below._x000D_ Flow cytometry/Cell sorting (1 paper)_x000D_ Monoclonal Anti-Human IgG4-FITC antibody produced in mouse has been used in immunohistofluorescence and immunofluorescence assay._x000D_ The IUIS/WHO2 study singled out this monoclonal antibody as one of the most widely applicable IgG4 specific monoclonal antibodies. Monoclonal Anti-Human IgG4 may be used for the identification of the IgG4 subclass by various immunoassays including: ELISA, Imprint Immunofixation (IIF), Immunofluorometric Assay (IFMA), Hemagglutination (HA), Hemagglutination Inhibition (HAI), Particle Counting Immunoassay (PACIA), and detection of cytoplasmic IgG._x000D_ Physical form_x000D_ Solution in 0.01 M phosphate buffer, pH 8.0, containing 1% inactivated bovine serum albumin and 15 mM sodium azide._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._x000D_ Biochem/physiol Actions_x000D_ IgG4 (Immunoglobulin G4) antibody has reduced affinity for C1q (first component of complement q) and hence its anti-inflammatory activity differs from that of the other IgG subclasses. IgG4 antibodies are known to actively interchange Fab arms with another molecule, resulting in recombined antibodies with two different binding specificities. This exchange is considered as an important biological mechanism that contributes to its anti-inflammatory activity. IgG4 antibodies are normally noninflammatory, but autoreactive IgG4 antibodies are known to be associated with Immunoglobulin G4 (IgG4)-related disease (IgG4-RD), characterized by infiltrating lymphoplasmacytic cells and elevated serum IgG4.