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 ...

Complement component 3, often called C3, is an essential protein of the immune system. This protein plays a vital role in the body’s innate immune system, providing: the first line of defense against ...

Undertaking a study of proteins found in the complement system, an important part of the immune system, of patients with long COVID, researchers have identified a blood protein ‘signature’ that may ...

Your complement system consists of a group of important proteins in your bloodstream. These proteins help your immune system fight off harmful invaders, such as bacteria, and other foreign substances.

The fact that the complement system is activated during immune-complex glomerular disease has been known for nearly 50 years. Detection of complement deposition in the glomerulus using immunochemistry ...

In a recent study posted to the bioRxiv* preprint server, researchers investigated the expression of complement regulatory proteins (CRPs) in coronavirus disease 2019 (COVID-19) to identify potential ...

These findings suggest complement protein levels may be an important biomarker for type 1 diabetes. Disruption of the complement system appears to precede the onset of islet autoimmunity (IA), making ...