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 ...

Complement 3 glomerulopathy (C3G) is a rare kidney disease that affects your body’s innate immune system (complement system). Complement 3 glomerulopathy (C3G) is a kidney disease that’s caused by ...

A complement C4 (also known as a complement component 4, or simply C4) is a test to measure the level of C4 proteins you have in your blood. These proteins play a role in how your immune system ...

Faults in a certain part of the immune system might be at the root of some long covid cases, new research suggests. For many people, covid is an illness that blusters in and out of our lives as cases ...