Immunoglobulin G (IgG) is a member of the immunoglobulin superfamily of glycoproteins that plays a central role in the adaptive immune response.1 It is produced by B cells and later secreted by plasma cells and is the most abundant circulating antibody in human and mouse serum.1,2,3 IgG consists of two heavy chains of approximately 50 kDa each and two light chains of approximately 25 kDa each.1 The heavy chains are linked together by disulfide bonds to form an Fc region and also combine with the light chains to form the Fab region, which mediate receptor and antigen binding, respectively.4 IgG is produced following IgM class-switching in response to infection and is involved in numerous humoral host defense responses, including antibody-dependent cell-mediated cytotoxicity (ADCC), toxin neutralization, and pathogen opsonization.2 IgG exists as four isotypes in humans, IgG1, IgG2, IgG3, and IgG4, each of which has a distinct effector function. IgG2 is primarily responsible for anticarbohydrate responses against bacterial polysaccharides but, unlike IgG1, IgG2 does not bind Fc receptors or induce Fc receptor-mediated effector functions.5 Maternal IgG2s are shared with the fetus via placental transfer and mothers of children born with group B streptococcal-induced sepsis have decreased serum levels of IgG2 compared with mothers of children born uninfected. Serum levels of IgG2 are also decreased in patients with recurrent infections with capsulated bacteria, sinopulmonary infections, and otitis media. IgG2 (human) Rabbit Monoclonal Antibody (Clone RM118) can be used for ELISA. The antibody recognizes the heavy chain of IgG2 from human samples.WARNING This product is not for human or veterinary use.
