The membrane attack complex (MAC)/perforin-like protein complement component 9 (C9) is the major component of the MAC, a multi-protein complex that forms pores in the membrane of target pathogens. In ...

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 complement receptor 1 (CR1) gene encodes a transmembrane glycoprotein that functions in the innate immune system. CR1 is expressed on blood cells and microglia. As a receptor for the complement ...

A complement blood test measures how well complement proteins in your blood support immune defense. The complement system helps antibodies fight germs and clear foreign substances. Complement testing ...