Complement System Activation by Amyloid Aggregates of Aβ(1-40) and Aβ(1-42) Peptides: Facts and Hypotheses

Abstract—Here, we consider the problem of the activation of the complement system by amyloid aggregates, in particular, amyloid fibrils of the Aβ(1-40) and Aβ(1-42) peptides found in the brain of patients with Alzheimer’s disease. In 1992, based on the data on colocalization of amyloid inclusions with complement system proteins in the brains of patients with this disease, it was suggested that this system is directly activated by amyloids. This hypothesis has been supported by a number of subsequent publications. However, in this study, we did not find evidence to support this idea. The issue remains as to whether amyloids activate the complement system, and, if not, which mechanism is responsible for its activation. Here, we try to elucidate these issues. © 2020, Pleiades Publishing, Inc.