Anti-I kappa B epsilon antibodies enable researchers to detect and measure the I kappa B epsilon antigen in biological samples. This target is a reported synonym of the NFKBIE gene, which encodes NFKB inhibitor epsilon. This protein is reported to inhibit NF-kappa-B by complexing with and trapping it in the cytoplasm. The human version of I kappa B epsilon has a canonical amino acid length of 500 residues and a protein mass of 52.9 kilodaltons. It is reported to be localized in the cytoplasm of cells and widely expressed in many tissue types. Other names for this target antigen include IKBE, NF-kappa-B inhibitor epsilon, and I-kappa-B-epsilon.