IS A COMPONENT OF AA AMYLOID

摘要

Agrin is a large heparan sulphate proteoglycan (HSPG) best known for its key role in acetylcholin receptor clustering in the neuromuscular synapse. The tissue distribution of agrin is widespread, and agrin has received increasing attention as new roles for this HSPG are disclosed.HSPGs are found associated with all amyloids, and most studies have focused on perlecan. However, a glomerular basement membrane HSPG demonstrated in AA and AL glomerular amyloid ten years ago was later confirmed to be agrin (1). Recently, agrin accumulation was demonstrated in Ap deposits {2) and in vitro agrin was shown to accelerate Abeta fibril formation as well as protect these fibrils from proteolysis (3).We have previously demonstrated that splenic GAGs increase in experimental AA induced in the mink and that HS is the dominating splenic GAG in mink (4).