Serum Amyloid P Component - in Amyloidosis

In Amyloidosis

AP makes up 14% of the dry mass of amyloid deposits and is thought to be an important contributor to the pathogenesis of a related group of diseases called the Amyloidoses. These conditions are characterised by the ordered aggregation of normal globular proteins and peptides into insoluble fibres which disrupt tissue architecture and are associated with cell death. AP is thought to decorate and stabilise aggregates by preventing proteolytic cleavage and hence inhibiting fibril removal via the normal protein scavenging mechanisms. This association is utilised in the routine clinical diagnostic technique of SAP scintigraphy whereby radio-labelled protein is injected into patients to locate areas of amyloid deposition. The SAP-amyloid association has also been identified as a possible drug target for anti-amyloid therapy, with the recent development and first stage clinical trials of a compound called CPHPC (R-1--6-oxohexanoyl] pyrrolidine-2-carboxylic acid), a small molecule able to strip AP from deposits by reducing levels of circulating SAP.