Extracellular matrix, amyloid fibrils and infections. Is there a new approach to combat amyloidosis?

Recent studies suggest that amyloid is an ancient, highly conserved effector molecule of innate immunity. This set ofiology model characterises amyloid deposition as an innate, chronic immune response that normally protects against microbial infection in the brain. Nonetheless, the fact that the amyloid is functionless remains widely held, despite evidence that the human Aß sequence is conserved across most vertebrate species, up to at least 400 million years. Growing amyloid fibrils capture, agglutinate, and finally entrap microbes in a resistant network of amyloid. Glycosaminoglycans (GAGs), which are major components of the extracellular matrix (ECM), are carbohydrate polymers. They are usually attached to ECM proteins to form proteoglycans and appear to enhance amyloid fibril formation. In general, GAGs are thought to facilitate amyloid fibril formation and stabilise amyloid aggregates. The antimicrobial protection hypothesis reveals how an increased brain microbial burden may directly exacerbate fibril deposition, inflammation and neurodegenerative disease progression, such as Alzheimer’s disease. Actually, therapeutics are severely limited, and no interventions are available to reverse the course of these diseases.