Clusterin (apolipoprotein J) is a 75-80 kDa disulfide-linked heterodimeric protein associated with the clearance of cellular debris and apoptosis. In humans, clusterin is encoded by the CLU gene on chromosome 8. CLU is a molecular chaperone responsible for aiding protein folding of secreted proteins, and its three isoforms have been differentially implicated in pro- or antiapoptotic processes. Through this function, CLU is involved in many diseases related to oxidative stress, including neurodegenerative diseases, cancers, inflammatory diseases, and aging.