It was called ‘complement’ because it aided the antibacterial activity of antibodies. However, it is now known that the complement system can be activated early in an infection without the presence of ...

The renin–angiotensin system (RAS), the complement system and the kallikrein–kinin system (KKS) each consists of a large number of distinct plasma and membrane-bound proteins and receptors that can ...

Long Covid patients suffer from chronic symptoms such as fatigue or shortness of breath. As researchers have discovered, this is to some extent due to a part of our immune system called the complement ...

Neutrophils make up approximately 70% of the white blood cells in humans and serve as a first line of defense against invading pathogens. Two mechanisms of action, the release of cytotoxic molecules ...

Among people with sickle cell disease—an inherited blood disorder—acute chest syndrome (ACS) is the leading cause of death. The condition is the result of red blood cells becoming stiff, sticky, and ...

C3 glomerulopathy (C3G) and immune complex membranoproliferative glomerulonephritis (IC-MPGN) are rare kidney conditions caused by an overactive complement system, part of the immune system. C3G ...