Format

Send to

Choose Destination
Mol Immunol. 2016 Mar;71:131-142. doi: 10.1016/j.molimm.2016.01.010. Epub 2016 Feb 16.

Complement gene variants determine the risk of immunoglobulin-associated MPGN and C3 glomerulopathy and predict long-term renal outcome.

Author information

1
IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Clinical Research Center for Rare Diseases Aldo e Cele Daccò, Ranica, Bergamo, Italy.
2
Unit of Nephrology and Dialysis, Azienda Ospedaliera Papa Giovanni XXIII, Bergamo, Italy.
3
Unit of Pediatric Nephrology, Dialysis and Transplantation, Azienda Ospedaliera of Padova, Italy.
4
Department of Immunology, Assistance Publique-Hopitaux de Paris, Hopital Europeen George-Pompidou and INSERM UMRS 1138, Cordelier Research Center, Complement and Diseases Team, Paris, France.
5
Division of Nephrology and Dialysis, Bambin Gesù Pediatric Hospital, Roma, Italy.
6
IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Clinical Research Center for Rare Diseases Aldo e Cele Daccò, Ranica, Bergamo, Italy. Electronic address: erica.daina@marionegri.it.
7
IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Clinical Research Center for Rare Diseases Aldo e Cele Daccò, Ranica, Bergamo, Italy; Unit of Nephrology and Dialysis, Azienda Ospedaliera Papa Giovanni XXIII, Bergamo, Italy; Department of Biomedical and Clinical Sciences, University of Milan, Milan, Italy.

Abstract

BACKGROUND:

Membranoproliferative glomerulonephritis (MPGN) is an uncommon cause of chronic nephropathy recently reclassified into immunoglobulin-associated MPGN (Ig-MPGN) and C3 glomerulopathy (C3G). In this study we aimed: (1) to evaluate the complement genetic and biochemical profile in patients with Ig-MPGN/C3G; (2) to investigate whether genetic variants and different patterns of complement activation (i.e., fluid versus solid phase) correlate with disease manifestations and outcomes.

METHODS:

In 140 patients with idiopathic Ig-MPGN or C3G we performed complement biochemical and genetic screening and correlated genetic, biochemical and histology data with clinical features.

RESULTS:

Mutations in genes encoding alternative pathway complement proteins were found in both Ig-MPGN and C3G, and mutations in the two components of the C3 convertase are the most prevalent. We also report a mutation in THBD encoding thrombomodulin in a C3G patient. The presence of mutations alone does not significantly increase the risk of Ig-MPGN or C3G, but it does so when combined with common susceptibility variants (CD46 c.-366A in Ig-MPGN; CFH V62 and THBD A473 in C3G). Finally, patients without complement gene mutations or C3NeFs--autoantibodies that stabilize the alternative pathway C3 convertase--have a higher risk of progressing to end-stage renal disease than patients with identified mutations and/or C3NeFs, suggesting the existence of different pathogenetic mechanisms that lead to renal disease.

CONCLUSIONS:

We provide new insights into the pathogenesis of Ig-MPGN/C3G that underscore the complex nature of these diseases and suggest that the current C3G classification may miss many cases associated with abnormalities of the complement alternative pathway.

KEYWORDS:

C3 glomerulonephritis; C3 glomerulopathy; Dense-Deposit Disease; Membranoproliferative glomerulonephritis; Rare diseases

PMID:
26895476
DOI:
10.1016/j.molimm.2016.01.010
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center