HNL/NGAL is a protein that is stored in and secreted from the secondary granules of human neutrophil granulocytes. As indicated by the name HNL/NGAL the protein belongs to the superfamily of lipocalins. Another name is Lipocalin 2. The biological function of HNL is uncertain although the protein was shown to bind a siderophore and therefore potentially acts as an iron-transporting protein. Among inflammatory cells HNL is uniquely found in neutrophils. HNL is also found in certain epithelial cells such as kidney tubular cells, gastrointestinal cells and in brain cells. HNL secreted from neutrophils may be the monomeric or the dimeric protein whereas epithelial cells only produce the monomeric form of HNL. We provide you with tools to study the biology of HNL. In particular our monoclonal antibodies specifically identify neutrophil granulocytes in tissues.