This antibody reacts with natural and recombinant human Serum Amyloid A (SAA) and does not cross-react with other human cytokines or growth factors. Human SAA proteins are a group of apo-lipoproteins found predominantly in the high-density lipoprotein (HDL) fraction of plasma. SAA is a major acute-phase protein and precursor to amyloid A protein, which is the major constituent of the fibril deposits of reactive amyloidosis. SAA is secreted in large amounts by the liver during microbial infections or inflammatory diseases.