Anti-NFKB inhibitor zeta antibodies are used in the immunodetection of the protein encoded by the NFKBIZ gene. In humans, the canonical protein has a reported length of 718 amino acid residues and a mass of 78.1 kDa. Its subcellular localization is in the nucleus. Alternative splicing is reported to yield 3 different isoforms for this protein. It is notably expressed at high levels in peripheral blood leukocytes and lung, at moderate levels in liver, placenta, and at low levels in spleen, kidney, skeletal muscle and heart. It is known to be involved in regulation of NF-kappa-B transcription factor complexes. Other names for this target antigen include IL-1 inducible nuclear ankyrin-repeat protein, molecule possessing ankyrin repeats induced by lipopolysaccharide, nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, zeta, and NF-kappa-B inhibitor zeta.