Amyloids are proteins that misfold and aggregate. These misfolded proteins are associated with more than 20 human diseases which can cause damage to organs. Amyloid can affect any organ in the body, including the brain and peripheral organs. For example, the misfolding and aggregation of the amyloid beta (Aβ) peptide leads to a build-up of amyloid protein in the brain, which most scientists believe is the primary cause of Alzheimer’s disease.
Amyloid proteins including amyloid light chain (AL), amyloid A (AA) and transthyretin amyloid (ATTR) are believed to cause toxicity in peripheral organs under pathological conditions. Collectively, the peripheral diseases caused by these proteins are known as systemic amyloidoses.
AL amyloidosis, also known as primary systemic amyloidosis, is the most common form of systemic amyloidosis. It is a progressive and often fatal disease. In AL amyloidosis, plasma cells from the bone marrow overproduce amyloid light-chains (AL), and misfold. These misfolded proteins aggregate into fibrils in the bloodstream (soluble) and are deposited (insoluble) in one or more vital organs. When these AL fibrils invade organs, including the heart, kidney, liver, skin, gastrointestinal tract, and/or the autonomic or peripheral nerves, they impede normal function of an organ.