Complement and

glomerular nephropathies

Philippe Lesavre

Université Paris Descartes INSERM U 845

Hôpital Necker, Paris

A. Recognition pathways

C. C3b amplication loop of the complement pathways

B. C3-C5 convertases

MASP C1

ficolin MBL CP

hydrolyse spontanée

discrimination des surfaces

FP, FH

C3

C3 convertases C5 convertases

C3

C3b

B, D

C3bBb

C3bFH

FH

iC3b +

C3g

FI

C3d

C3bBb

C3b chain reaction

C3bBb

P

C3a

+

C3

terminal complex

C3b

C7 C6 C9 C8 C9 C5b

C3bBb

C4bC2a

C3b C5b

C5a

+

C3bBb

C4bC2a

C5

FI

MCP

C3b FH

iC3b C3d +

C3g

CR1

FI

DAF

FI

C3b

C3b

Control of C3b in fluid phase

Control of C3b on cell surfaces

The complement for dummies (and for Doumé)

Ca

+

Cb C

proteases

TEP1 TEP1

+

« In the beginning was ….. »

Blandin SA et al., Cell Host & Microbes, 2008

Microbial proteases

Blandin SA et al, Methods Mol Biol., 2008

Su X et al., Nat Rev Genet., 2007

TEP1 KO

Blandin S et al., Cell, 2004

« In the beginning was ….. »

Blandin et al, Methods Mol Biol., 2008

TEP1 TEP1

+

Microbial proteases

C3a

+

C3b C3

C3 convertases

C3a

+

C3b C3

C3

C3b

B, D

C3bBb

P

C3b chain reaction

C3 convertases

C3bFH

FH

iC3b

+

C3g

FI

C3d

Control of C3b in fluid phase

C3bBb C3bBb

Control of C3b on cell surfaces

FI

MCP

C3b FH

iC3b C3d +

C3g

CR1

FI

DAF

FI

.

C3b

C3b

C3b amplication loop of the complement pathways

C3

C3b

B, D

C3bBb

P

C3a +

C3 C3b

C3b chain reaction

C3 convertases

C3 convertases

B. C3-C5 convertases C3a

+

C3 C3b

C3bBb

C4bC2a

C3-C5 convertases

C5

C3b

C3b

C5 convertases

C7 C6 C9 C8 C9 C5b

C5b

C5a

+

C3bBb

C4bC2a

terminal complex

hydrolysis spontaneous

surface discrimination

FP, FH

C3

C3 convertases C5 convertases

C3b

B. C3-C5 convertases C3a

+

C3 C3b

C7 C6 C9 C8 C9 C5b

C3bBb

C4bC2a

C3b C5b

C5a

+

C3bBb

C4bC2a

C5

Alternative pathway

A. Recognition pathways

terminal complex

Lectin pathway

MASP

ficolin MBL

C3 convertases C5 convertases

C3b

B. C3-C5 convertases C3a

+

C3 C3b

C7 C6 C9 C8 C9 C5b

C3bBb

C4bC2a

C3b C5b

C5a

+

C3bBb

C4bC2a

C5

Voie classique

A. Recognition pathways

terminal complex

C1

CP

C3 convertases C5 convertases

C3b

B. C3-C5 convertases C3a

+

C3 C3b

C3bBb

C4bC2a

C3b

C7 C6 C9 C8 C9 C5b

C5b

C5a

+

C3bBb

C4bC2a

C5

Classical pathway

A. Recognition pathways

terminal complex

A. Recognition pathways

B. C3-C5 convertases

MASP C1

ficolin MBL CP

C3

C3 convertases

C3a

+

C3 C3b

C3bBb

C4bC2a

C3b

C5 convertases

terminal complex

C7 C6 C9 C8 C9 C5b

C5b

C5a

+

C3bBb

C4bC2a

C5

C. C3b amplication loop of the complement pathways

Control of C3b on cell surfaces

C3bBb

C3bFH

FH

C3bBb

C3b chain reaction

C3bBb C3b FH

C3b

C3b

C3

C3b

B, D

iC3b +

C3g

FI

C3d

P

FI

MCP

iC3b C3d +

C3g

CR1

FI

DAF

FI

Control of C3b in fluid phase

hydrolysis spontaneous

surface discrimination

FP, FH

The C3b amplification loop of the complement pathways

Hyperactivation - physiological - pathological

Normal

- acquired - genetic

C3 complophilia

Lupus

Mice models MPL/lpr mice

FB, FD deficiencies prevent FH deficiency aggravates

Human

Deposits : IgG, C4 C3, FB, FP correlate with severity MBL

Hyperactivation

Lupus

ANCA

Hyperactivation

Mice models

FB deficiency prevention FH deficiency aggravation C5a receptor blockade : prevention

Human

role of neutrophil properdin

Mice deficient in factor B but not C4 are resistant to anti-MPO IgG-induced NCGN

Xiao H, Am J Pathol; 2007

% crescents % necrosis

Amplification loop of the complement pathways are activated by neutrophils

Camous L et al., Blood. 2011; 117:1340

C5a Receptor (CD88) blockade protects against MPO-ANCA GN

Xiao H et al.,J Am Soc Nephrol 25: 225–231, 2014

Lupus

ANCA

Immune complexes

Hyperactivation

Lupus

ANCA

Immune complexes

Autoantibodies

Hyperactivation

Lupus

ANCA

Immune complexes

Autoantibodies

IgA nephropathy

Hyperactivation

Lupus

ANCA

Immune complexes

Autoantibodies

IgA nephropathy

Non glomerular diseases

Adriamycin tubulo-interstitial lesions Collagen-induced arthritis Renal ischemia reperfusion Ischemic stroke

Mice models : prevention by CFB deficiency

Hyperactivation

C3 glomerulopathies

MPGN I

IF predominant deposits C3 C3+C4+Ig

acute chronic

GNA DDD MPGN II

C3GN MPGN I

C3 glomerulopathies vs MPGN I

MPGN type I: immune complexes

Gubler MC, 1978

C3 glomerulopathies

MPGN I

IF predominant deposits C3 C3+C4+Ig

acute chronic

GNA DDD MPGN II

C3GN MPGN I

C3 glomerulopathies

C3 glomerulopathies

MPGN I

IF predominant deposits C3 C3+C4+Ig

acute chronic

GNA DDD MPGN II

C3GN MPGN I

Necker 1970-1982 (n) 27 31 175

Multicentric 2000-2009 (n) 29 56 *

C3 glomerulopathies

Servais et al, Kidney Int, 2012

* <16 yrs = 52

familial, 11%

Acute post-streptococcal GN

Gubler MC, 1978

C3 glomerulopathies

MPGN I

IF predominant deposits C3 C3+C4+Ig

acute chronic

GNA DDD MPGN II

C3GN MPGN I

EM

intra-memb ± +++ ±

humps +++ + ± to +++

sub-endoth ± + ± to +++

mesangial ± ++ + to +++

LM

memb-prolif - ≈ 50% 70 100%

mesangial - ≈ 50% 30

C3 glomerulopathies versus MPGN type I

Dense deposits disease : DDD (MPGN type II)

Gubler MC, 1978

partial lipodystrophy after a measle attack

C3 nephritic factor

renal failure

recurrence after transplantation

Oxford TN, 2005

MCGN type II (DDD)

• central scotoma (50 yrs old) serous detachment,

hemorrhage (choroidal neovascularization) late fibrovascular scarr drüsen

• early change (child) small hard drüsen

Ocular changes in type 2 MCGN (DDD)

Leys et al. , Eur J Ophtalmol, 1991

Oxford TN, 2005

C3 glomerulopathies

MPGN I

IF predominant deposits C3 C3+C4+Ig

acute chronic

GNA DDD MPGN II

C3GN MPGN I

EM

intra-memb ± +++ ±

humps +++ + ± to +++

sub-endoth ± + ± to +++

mesangial ± ++ + to +++

LM

memb-prolif - ≈ 50% 70 100%

mesangial - ≈ 50% 30

C3 glomerulopathies versus MPGN type 1

C3 GN : mesangial

Gubler MC, 1978

C3 GN : sub-endothelial + mesangial

Gubler MC, 1978

C3 GN : complex (MPGN type 3)

Gubler MC, 1978

C3 glomerulopathies: outcome

Medjeral-Thomas NR et al., Clin J Am Soc Nephro, 2014

Hyperactivation - physiological - pathological

Normal

- acquired - genetic

C3 complophilia

C3 complophilia in C3 glomerulopathy

Acquired

Auto-ab C3NeF anti-CFH Anti-CFB

Genetic

C3 nephritic factor

C3a

+ C3b C3

C3

C3b

B, D

C3bBb

P

MPGN 1

MPGN 1

C3Nef (45%)

CFH (nd)

C3 glomerulopathies

acute chronic

GNA DDD C3GN

acquired

auto-ab

C3Nef (trans) C3Nef (85%) C3Nef (45%)

CFH (nd) CFB (nd)

CFH (nd)

C3 complophilia in C3 glomerulopathies

Servais et al, Kidney Int, 2012 Frémeaux-Bacchi V, personnal communication

… and immune complex GN (MPGN type 1)

C3 complophilia in C3 glomerulopathy

Acquired

Auto-ab C3NeF anti-CFH Anti-CFB

Genetic

Mutations CFH CFHR CFHR hybrids

Variants C3 CFH

Levy , et al., Kidney Int. 1986

Levy , et al., Kidney Int. 1986

Levy , et al., Kidney Int. 1986

CFH

GAG Polyanion C3b, C3d

CRP

GAG Polyanion

CRP

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 17 18 19 20 16

C3b

C3-convertase dissociation

CFI cofactor

C3b 1

2

3

12 13

20

19

7

C3b

Ligand

Fonction

Bb

Cell binding

C3d

C3b

Polyanion

Polyanion

Cell binding

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

C3GN

HUS Servais et al, Kidney Int, 2012

low

normal CFH (serum)

CFH mutations in C3 GN versus HUS

Frémeaux-Bacchi V, personnal communication

C3 glomerulopathies

acute chronic

GNA DDD C3GN

acquired

auto-ab

C3Nef (trans) C3Nef (85%) C3Nef (45%)

CFH (nd) CFB (nd)

CFH (nd)

genetic

mutations rare 17% CFH CFI

CFH-CFHR5

≈ 20% CFH CFI

CFHR5

variants C3 R102G CFH H402Y

CFH poly

C3 complophilia in C3 glomerulopathies

Servais et al, Kidney Int, 2012 Frémeaux-Bacchi V, personnal communication

C3 glomerulopathies

MPGN 1

acute chronic

GNA DDD C3GN MPGN 1

acquired

auto-ab

C3Nef (trans) C3Nef (85%) C3Nef (45%) C3Nef (45%)

CFH (nd) CFB (nd)

CFH (nd)

CFH (nd)

genetic

mutations rare 17% CFH CFI

CFH-CFHR5

≈ 20% CFH CFI

CFHR5

20% CFH CFI

variants C3 R102G CFH H402Y

CFH poly

C3 complophilia in C3 glomerulopathies

… and immune complex GN (MPGN type 1)

Servais et al, Kidney Int, 2012 Frémeaux-Bacchi V, personnal communication

5’ 3’

The locus of the regulators of complement activity (RCA) on chromosome 1q32

Joszi M and Zipfel PF, Trends Immunol; 2008

CFHL1 1 2 3 4 6 7 5

CFH 1 2 3 4 6 7 8 9 5 10 11 12 13 14 15 16 17 18 19 20

CFHR1A/B

CFHR2

CFHR3

CFHR4A

CFHR4B

CFHR5

3 4 5

3

3

4

5 4 1 2

2 1

2 1

4 5

9 3 4 5 6 2 1

1 2 3

7

4

8 9

1 2

6 7 5

3

Structure/Fonction of CFHR family proteins

Inhibition de la C5-convertase Compétition avec CFH pour C3b

Compétition avec CFH pour C3b Augmente activité cofacteur de CFH

Augmente activité cofacteur de CFH

Dissociation C3-convertase Cofacteur de FI Liaison aux cellules

Liaison C3b Inhibition complexe C5b-9 terminal

Faible dissociation C3-convertase et activité cofacteur de FI, Liaison C3b Inhibition complexe C5b-9 terminal

8

Joszi M and Zipfel PF, Trends Immunol; 2008

CFHR5 nephropathy - apparently monogenic - Cypriot population

Clinically - persistent microscopic haematuria with or without episodic synpharyngitic macroscopic haematuria in the early stages - hypertension and progressive renal failure. - absence of high-grade proteinuria (>3 g per day) or nephrotic syndrome - renal impairment over 50 years : 80% of men, 20% of women

C3 level : normal

C3 glomerulopathy (mesangial) - without dense transformation of the GBM

Transplantation - evidence of glomerular complement deposition in all allografts biopsied - good graft outcomes

Gale DP; NDT, 2012

CFHR5 nephropathy

9 3 4 5 6 2 1 7 8

9 3 4 5 6 2 1 7 8 2 1

CFHR5 internal duplication

CFHR5

3 4 2 1

9 4 5 6 2 1 7 8

CFHR2

CFHR5

DDD

CFHR2/CFHR5 hybrid

x2

CFHR5 nephropathy

CFHR2-CFHR5 activity

Chen Q, J Clin Invest. 2014

C3 convertase formation was enhanced by 70% and more resistant to factor H–mediated decay

________________________________

1. Complement proteins serum levels C3, C4 CFB CFH, CFI soluble C5b-9

2. Autoantibodies Anti-CFH Anti-CFB C3 NeF

3. Sequencing for genes mutations CFH, CFHR5, CFI, C3

4. Analysis for CFH and CFHRs regions rearrangement 5. Monoclonal gammopathy detection ________________________________

Laboratory investigation of C3-complophilia in C3 glomerulopathies

Véronique Frémeaux-Bacchi, HEGP

C3-C5 convertases

Katschke KJ Jr et al., J Biol Chem. 2012 Paixa o-Cavalcante D et al., J Immunol, 2014

C3 convertases C5 convertases

C3b

C3a

+

C3 C3b

C7 C6 C9 C8 C9 C5b

C3bBb

C4bC2a

C3b C5b

C5a

+

C3bBb

C4bC2a

C5

C3b terminal complex

C3

C3b

B, D

C3bBb

P

Zuber J et al. Nature Reviews Nephrol

Eculizumab

Xiao H et al.,J Am Soc Nephrol, 2014

C5a receptor antagonist

anti-factor D Fab

Factor H infusion mAb anti-C3 convertase