The complement system has vital protective functions as a humoral component of the innate immune system and also through interactions with the adaptive immune system; however, when inappropriately ...

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.

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 ...