C3 NEPHRITIC FACTOR IN A PATIENT WITH RECURRENT NEISSERIA MENINGITIDIS INFECTIONS

Publisher Website
Google Scholar
Abstract
A 15 yr old female experienced 2 systemic infections with N. meningitidis (group C and B) within a 2 mo. period. Classical and alternative pathway total hemolytic complement determinations on her serum showed no lysis. All individual complement factor concentrations, except for C3, were within the reference area. Crossed immunoelectrophoretic analysis of C3 revealed no demonstrable native C3. The patient had normal levels of C3c and a markedly elevated C3d concentration. Serum from the patient converted all native C3 in normal sera within 10 min at 37.degree. C. The active converting principle, present in the IgG fraction, activated C3 in C4-depleted serum and had a dose-dependent stabilizing effect on the erythrocyte-antibody-C3bBb complex. The isolated factor showing the characteristics of C3 nephritis factor was unchanged in her serum over a 10 mo. observation period. Circulating immune complexes (IC) could not be demonstrated by a C1q-dependent assay but the patient''s capacity to solubilize performed IC in vitro was virtually abolished. The patient had no signs of renal disease of lipodystrophy.

This publication has 32 references indexed in Scilit: