Anti-Human IgG2 [Clone HP6014] - Purified No Carrier Protein (I-1224-250ug)

Humans produce five classes of immunoglobulins, IgM, IgD, IgA, IgE, and IgG1. IgG is the most abundant class1 and functions in the humoral immune response2. There are four subclasses of IgG, and they are numbered according to decreasing abundance as IgG1 through IgG4. The four subclasses are highly conserved and consist of four polypeptide chains: two identical heavy chains and two identical light chains1. While the general structure is very similar between IgG subclasses, differences in their constant regions in the hinge and upper CH2 domain as well as in glycosylation affect their binding to antigens (e.g. pathogenic proteins, polysaccharides, allergens), C1q and Fc receptors, leading to differences in functionality. As a result, each IgG subclass has a unique response skewed to specific antigens. IgG2 responds to bacterial capsular polysaccharide antigens1. Relative to the other IgG subclasses, IgG2 has a short, rigid hinge. Several structural hinge isomers exist, differing in the hinge region’s inter-chain disulfide bonds. IgG2 is less efficient at triggering C1q complement activation than IgG1 and IgG3 due to a leucine-to-alanine substitution at residue 235. Additionally, the short hinge may shield the C1q binding site. However, IgG2 can efficiently activate the complement cascade in the presence of high densities of polysaccharides. IgG2 also has a relatively reduced affinity for a number of FcγR. HP6014 was generated by immunizing a BALB/c mouse with purified human immunoglobulin3. Spleen cells were fused with Sp2/0-Ag14 myeloma cells.