Table 1.

Specificity and clinical associations of nephritic factors.

	Epitope	Clinical association (frequency)
C3NeF	Neoepitope on assembled C3 convertase of the AP (C3bBb)	C3GN (40–50%) and DDD (70–80%) (7, 24, 25, 33, 34) IC-MPGN (40–50%) (34, 35) APL (70-80%) (36, 37) SLE*
C4NeF	Neoepitope on assembled C3/C5 convertase of the CP/LP (C4b2a or C4b2aC3b)	C3G and IC-MPGN (3–9%) (38–40) SLE*
C5NeF	Neoepitope on assembled C5 convertase of the AP (C3bBbC3bP)	C3GN (67%) and DDD (33%) (24)

AP, alternative pathway; CP, classical pathway; LP, lectin pathway; C3G, C3 glomerulopathy; DDD, dense deposit disease; IC-MPGN, immune complex-associated membranoproliferative glomerulonephritis; APL, acquired partial lipodystrophy; SLE, systemic lupus erythematosus; C3GN, C3 glomerulonephritis

^*The frequency of C3NeF and/or C4NeF in SLE has not been thoroughly investigated.