Serum C′3 Lytic System in Patients with Glomerulonephritis

Abstract

The serums of patients with hypocomplementemic glomerulonephritis contain a substance that combines with a normal serum cofactor in the presence of magnesium ion to specifically cleave the third component of complement. This lysis of C′3 is 80 to 90 percent complete in 20 minutes at 37°C and p H 7. Neither the nephritic factor nor its cofactor is identifiable with the complement system.