<P> Diagnostic tools to measure complement activity include the total complement activity test . </P> <P> The presence or absence of complement fixation upon a challenge can indicate whether particular antigens or antibodies are present in the blood . This is the principle of the complement fixation test . </P> <P> Recent research has suggested that the complement system is manipulated during HIV / AIDS to further damage the body . </P>

Where are the proteins in the complement system produced