The antibody MEM-09 reacts with both secreted and B cell-surface human immunoglobulin, specifically reacts with kappa light chains (22.5 kDa). Material immunoprecipitated from human serum with the antibody MEM-09 consists of IgG and traces of IgM.
Immunoglobulin classes share the same basic four polypeptide chain structure of two heavy chains (five heavy chains types) and two light chains (kappa, lambda, both having a molecular weight of 22.5 kDa). Kappa and lambda consist of a variable region and a constant region and can easily be differentiated by the antigenic properties of the constant region. The ratio of kappa to lambda is 70:30.,Immunoglobulin kappa, Igk