Clusterin (apolipoprotein J) is a 75 - 80 kDa disulfide-linked heterodimeric protein associated with the clearance of cellular debris and apoptosis. This protein has several synonyms: dimeric acidic glycoprotein (DAG protein), testosterone repressed prostate message-2 (TRPM-2), sulfated glycoprotein-2 (SGP-2) and complement lysis inhibitor (CLI).This protein was first identified in 1988 in seminal fluid.In humans the gene is encoded on chromosome 8 (8p21) and is highly conserved between species (70-80% homology).It is expressed in most mammalian tissues and can be found in blood plasma, milk, urine, cerebrospinal fluid and semen. A number of proteins have been found to affect its expression including Egr-1, members from the AP-1 complex, HSF1/2, Cdx1/2 and B-Myb.