1. Journal conference
Molecular Architecture of the Goodpasture Autoantigen in Anti-GBM Nephritis
Vadim Pedchenko, Ph.D., Olga Bondar, Ph.D., Agnes B. Fogo, M.D.,
Roberto Vanacore, Ph.D., Paul Voziyan, Ph.D., A. Richard Kitching, M.D., Ph.D.,
Jorgen Wieslander, M.D., Ph.D., Clifford Kashtan, M.D.,
Dorin-Bogdan Borza, Ph.D., Eric G. Neilson, M.D., Curtis B. Wilson, M.D.,
and Billy G. Hudson, Ph.D.
N Engl J Med July 22, 2010;363:
by the Tuberculosis Network European Trials Group (TBNET)
R2. Shin A-ri / Prof. Ihm Chun gyoo

2. Korea National Diabetes Program
Background
Goodpasture’s disease
: organ-specific autoimmune disease characterized by rapidly progressive
glomerulonephritis, pulmonary hemorrhage, glomerular pathological findings
that include linear deposits of antibodies along the GBM.
Alport’s post-transplantation nephritis (APTN)
: mediated by alloantibodies against the GBM, occurs after KTP in some patients
(3-5%) with Alport’s syndrome, result in allograft loss.
Target GBM antigen for circulating antibodies identified as
noncollagenous-1 (NC1) domain of α3 chain of collagen IV in GBM,
assembled into collagen IV a/w α3, α4, and α5 chains, forming α345NC1 hexamer
Korea National Diabetes Program
Mediated by the deposition of alloantibodies to the α3NC1 & α5NC1 domains
in response to the “foreign” α345 collagen network that is absent in the kidneys
of patients with Alport’s syndrome but, present in the renal allograft

3. Korea National Diabetes Program
ddddk
Background
Goodpasture’s disease
α345NC1 hexamer is targeted by Ab that arise in Goodpasture’s dis & APTN
But, the specificity & molecular architecture of epitopes of tissue-bound
autoantibodies are unknown
Korea National Diabetes Program
Jones’s silver stain
fluorescein-labeled antihuman IgG antibody

4. Korea National Diabetes Program
ddddk
Purpose
Goodpasture’s disease
; autoAb require hexamer
dissociation to unmask
hidden epitopes
Alport’s post-transplantation nephritis
; alloantibodies bind epitopes
exposed on native hexamer
Compare the conformation of the antibody epitopes
Korea National Diabetes Program
Intention of finding clues to the pathogenesis of
anti-GBM glomerulonephritis

5. Korea National Diabetes Program
Methods
Serum and tissue samples
- Serum samples ; circulating antibodies
57 patients with anti-GBM glomerulonephritis
samples were collected before plasma exchange or immunosuppressive drug
treatment was initiated
- Tissue samples ; kidney-bound antibodies
14 patients with Goodpasture’s disease, 2 patients with Alport’s post
-transplantation nephritis
Used an enzyme-linked immunosorbent assay
to determine the specificity of circulating autoantibodies and kidney-bound
antibodies to NC1 domains
Molecular architecture of key epitope regions
deduced with the use of chimeric molecules and a three-dimensional model
of the α345NC1 hexamer.
Korea National Diabetes Program

6. Korea National Diabetes Program
Results
1. Clinical data
2. Specificity of Circulating and Kidney-Bound Abs
3. Circulating α3NC1 & α5NC1 AutoAb
/ Epitope mapping Goodpasture’s Ab
4. Epitope mapping for kidney-bound autoAb and alloAb
5. Association of α3NC1 and α5NC1 autoantibodies with dis. activity
6. Three-dimensional structure of the α345NC1 hexamer
7. Conformational diversity and differential reactivity
Korea National Diabetes Program

7. 1. Clinical data Clinical data - retrospective study
- serum samples from 57 patients with Goodpasture’s disease
median age of patients at the time of Dx : 59 yrs
22 pts (41%) had positive results for myeloperoxidase ANCA
lung involvement : 46 pts / overt lung hemorrhage : 12 pts
- Follow-up information was available for 50 of the 57 patients after 6 months
17 pts (34%) remains alive with stable kidney function, 21 pts (42%) were
treated with dialysis, and 12 pts (24%) had died.
Linezolid 복용기간이 길어질수록 복용 용량이 많을 수록 부작용의 빈도가 높아짐.

8. 2. Specificity of Circulating (B,C,D) and Kidney-Bound (E) Abs
Linezolid 복용기간이 길어질수록 복용 용량이 많을 수록 부작용의 빈도가 높아짐.
Horizontal line
; median
Dotted line
; mean+3SD
for NL sample

9. 3. Circulating α3NC1, α5NC1 AutoAb (A) / Epitope mapping Goodpasture’s Ab
Linezolid 복용기간이 길어질수록 복용 용량이 많을 수록 부작용의 빈도가 높아짐.
Extent of binding of α3NC1 & α5NC1 IgG
Ab to NC1 hexamers from N-GBM & D-GBM.
α1NC1 & α5NC1 amino acid sequences corresponding to EA & EB regions of α3NC1

10. 4. Epitope mapping for kidney-bound autoAbs and alloAbs
Linezolid 복용기간이 길어질수록 복용 용량이 많을 수록 부작용의 빈도가 높아짐.
Binding of circulating, kidney & lung-bound
autoantibodies to N-GBM & D-GBM NC1 hexamers
in samples from 1 Goodpasture pts & 2 APTN pts.
c.f) hIgG : normal human IgG
Circulating antibodies from 27 Goodpasture pts & kidney eluates from 14 other Goodpasture pts

11. 5. Association of α3NC1 and α5NC1 autoantibodies with disease activity
Linezolid 복용기간이 길어질수록 복용 용량이 많을 수록 부작용의 빈도가 높아짐.
α3NC1
α5NC1

12. 6. Three-dimensional structure of the α345NC1 hexamer
Linezolid 복용기간이 길어질수록 복용 용량이 많을 수록 부작용의 빈도가 높아짐.

13. 7. Conformational diversity and differential reactivity of α345 NC1 hexamers of GBM
Linezolid 복용기간이 길어질수록 복용 용량이 많을 수록 부작용의 빈도가 높아짐.

14. Korea National Diabetes Program
Conclusion
The development of Goodpasture’s disease may be considered
an autoimmune “conformeropathy” that involves perturbation
of α345NC1 hexamer, inducing a pathogenic conformational change
in the α3NC1 and α5NC1 subunits, which in turn elicits an autoimmune
response.
Korea National Diabetes Program