[ELISA for detection of SC5b-9 levels in plasma and its clinical significance in SLE disease].

Using IgG from rabbit antiserum to human MAC neoantigens and SC5b-9, we established a sandwich ELISA for detecting SC5b-9 levels in human plasma. SC5b-9 was measured in 51 normal plasma samples and 40 plasma samples from patients with SLE. We found that SC5b-9 levels in 96.1% of the controls and in 78.9% of the patients with inactive SLE were below 450 ng/ml, while SC5b-9 levels in 81.0% of the patients with active SLE were above 450 ng/ml. This shows that SC5b-9 levels may be useful for diagnosing patients with clinically active SLE.