CLINICAL RESEARCH
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Antibody-Mediated Rejection Due to Preexisting versus
De Novo Donor-Specific Antibodies in Kidney Allograft
Recipients
Olivier Aubert,* Alexandre Loupy,*
†‡
Luis Hida lgo,
§|
Jean-Paul Duong van Huyen,
¶
Sarah Higgins,** Denis Viglietti,*
††
Xavier Jouven,* Denis Glotz,*
††
Christophe Legendre,*
†‡
Carmen Lefaucheur,*
††
and Philip F. Halloran
|‡‡
*Paris Translational Research Center for Organ Transplantation, Institut National de la Santé et de la Recherche Médicale,
Unité Mixte de Recherche-S970, Paris, France;
†
Paris Descartes University, Sorbonne Paris Cite, Paris, France;
‡
Kidney
Transplantation Department and
¶
Department of Pathology, Necker Hospital, Assistance Publique–Hôpitaux de Paris, Paris, France;
§
Department of Laboratory Medicine and Pathology and
‡‡
Department of Medicine, Division of Nephrology and Transplant
Immunology, University of Alberta, Edmonton, Alberta, Canada;
|
Alberta Transplant Applied Genomics C entre, Edmonton, Alberta ,
Canada; **Department of Nephrology, Sherbrooke University , Sherbrooke, Québec, Canada; and
††
Department of Nephrology
and Organ Transplantation, Saint-Louis Hospital, Assistanc e Publique–Hôpitaux de Paris, Paris, France
ABSTRACT
Antibody-mediated rejection (ABMR) can occur in patients with preexisting anti-HLA
donor-specific antibodies (DSA) or in patients who develop de novo DSA. However,
how these processes compare in terms of allograft injury and outcome has not been
addressed. From a cohort of 771 kidney biopsy specimens from two North American
and five European centers, we performed a systematic assessment of clinical and
biologic parameters, histopathology, circulating DSA, and allograft gene expression
for allpatients withABMR (n=205). Overall,103 (50%) patients had preexisting DSA and
102 (50%) had de novo DSA. Compared with patients with preexisting DSA ABMR,
patients with de novo DSA ABMR displayed increased proteinuria, more transplant
glomerulopathy lesions, and lower glomerulitis, but similar levels of peritubular capil-
laritis and C4d deposition. De novo DSA ABMR was characterized by increased expres-
sion of IFNg-inducible, natural killer cell, and T cell transcripts, but less expression of
AKI transcripts compared with preexisting DSA ABMR. The preexisting DSA ABMR had
superior graft survival compared with the de novo DSA ABMR (63% versus 34% at
8 years after rejection, respectively; P,0.001). After adjusting for clinical, histologic,
and immunologic characteristics and treatment, we identified de novo DSA ABMR
(hazard ratio [HR], 1.82 compared with preexisting DSA ABMR; 95% confidence interval
[95% CI], 1.07 to 3.08; P=0.03); low eGFR (,30 ml/min per 1.73 m
2
) at diagnosis
(HR, 3.27; 95% CI, 1.48 to 7.23; P,0.001); $0.30 g/g urine protein-to-creatinine ratio
(HR, 2.44; 95% CI, 1.47 to 4.09; P,0.001); and presence of cg lesions (HR, 2.25; 95% CI,
1.34 to 3.79; P=0.002) as the main independent determinants of allograft loss. Our
findings support the transplant of kidneys into highly sensitized patients and should
encourage efforts to monitor patients for de novo DSA.
J Am Soc Nephrol 28: 1912–1923, 2017. doi: https://doi.org/10.1681/ASN.2016070797
One of the most important objectives in
transplantation is avoidance of antibody-
mediate d rejection (ABMR), the princi-
pal cause of allograft loss .
1–3
ABMR can
occur in patients with preexisting anti-
HLA donor-specific antibodies (DSA) or
in patie nts without DSA at transplanta-
tion but who d evelop de novo DSA.
Preexisting DSA ABMR is uncommon:
most centers avoid tran splantation of
DSA-positive patients because it reduces
surv ival versus DS A-negative patients,
especially in transplantation using kidneys
from expanded criteria donors.
4,5
How-
ever, the increase in sensitized patients
and the absence of a sufficient flow of po-
tential matched donors have induced new
strategies to allow access to transplantation
for hig hly sensitized patients.
6–9
Thus,
carefully selected and managed transplants
in patients with pree xisting DSA have good
outcomes and, despite their risks, have bet-
ter survival and quality of life than if they
had remained on dialysis.
10–12
Although preexisting DSA constitutes a
relative contraindication to transplantation,
Received July 24, 2016. Accepted December 10,
2016.
O.A. and A.L. contributed equally to this work.
Published online ahead of print. Publication date
available at www.jasn.org.
Correspondence: Dr. Alexandre Loupy, Paris
Translational Research Center for Organ Transplantation,
INSERM, UMR-S970, 56 rue Leblanc, 75015 Paris,
France. Email: alexandreloupy@gmail.com
Copyright © 2017 by the American Society of
Nephrology
1912 ISSN : 1046-6673/2806-1912 JAmSocNephrol28: 1912–1923, 2017
the advantages of transplantation over di-
alysis and the encouraging results in spe-
cialized centers in selected DSA-positive
transplants have encouraged more cen-
ters to offer transplantation to selected
DSA-positive patients.
11
These results
are not restricted to the deceased donor
(DD) because a recent study showed that
patients who received kidney transplants
from HLA-incompat ible living donors
had a better survival benefit as compared
with patients who did not undergo trans-
plantation and those who waited for
transplants from DDs.
13,14
Todate,littleisknownofthe differences
between ABMR with preexisting and
ABMR with de novo DSA. Such compari-
sons need patients selected from multiple
centers to offset differences in center-
specific practices and to represent the
full spectrum of ABMR scenarios for epi-
demiologic and mechanistic compari-
sons.
3,15,16
Preexisting DSA A BMR has
been mainly studied in highly specialized
centers without a real comparison with
the de novo DSA ABMR, in terms of phe-
notypes and outcomes.
To address this issue, we conducted a
study of extensively phenotyped kidney
recipients, including conventional and
molecular features, the latter from micro-
array-based gene expression in biop-
sies.
17,18
Our aim was to develop a better
understanding of the phenotypes, mech-
anistic differences, and determinants of
prognosis across the entire spectrum of
ABMR phenotypes, focusing on the com-
parison of ABMR with preexisting versus
de novo DSA. The result is a multicenter
observational study intended to define the
determinants of outcome within the en-
tire ABMR population, and to highlight
potential leverage points for improving
clinical outcomes.
RESULTS
Baseline Characteristics of the
Kidney Transplant Recipients and
Donors
From a cohort of 771 kidney biopsies
from two North American and five Eu-
ropean centers, we selected all patie nts
(one biopsy per patient) w ith ABMR
Figure 1. Early occurence of preexisting anti-HLA DSA ABMR and superior graft surviva l
compared with de novo anti-HLA DSA AB MR. (A) Cumulative incidence of onset ABMR
accor ding to the DSA characteri stics (preexisting DSA versus de novo DSA). (B) Probability
of graft survival on the basis of DSA c haracteristics. (C) P robability of graft survival ac-
cording to the DSA characteristics and the presence or absence of cg lesions. cg+ve, cg-
positive; cg-ve, cg-negativ e.
J Am Soc Nephrol 28: 1912–1923, 2017 Preexisting versus De Novo DSA 1913
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CLINICAL RESEARCH
that were suitable for classification: 103
(50.2%) with preexis ting/persisting DSA
and 102 (49.8%) with de novo DSA. The
DSA were screened at the time of tran s-
plantation and at the time of ABMR by
single antigen beads. The preexisting
DSA were the same at the time of tran s-
plant a nd at t he time of the biopsy.
Pati ents without DSA at the time of the
biopsy were excluded.
The baseline and immunologic char-
acteristics are presented in Tabl e 1. The
mean recipient age was si milar between
the two groups, but the preexisting DSA
ABMR group had more DDs (n=93,
90.3%) compared w ith the de novo
DSA ABMR group (n=65, 64.4%;
P,0.001). The mean donor age in the
preexisting DSA ABMR group was older
(48615 years versus 43619 years) than
that in the de novo DSA ABMR group
(P=0.04). The median time of diagnosis
of ABMR was 388 days (interquartile
range [IQR], 76–1 550 days). According
to the DSA status, the median time of
diagnosis of ABMR in the preexisting
DSA ABMR g roup was muc h earlier:
85 days (IQR, 17– 369 days) versus
1437 days (IQR, 437 –3127 d ays) in the
de novo DSA ABMR g roup (Figure 1A).
The median follow-up time after biopsy-
proven ABMR was longer: 4.90 years
(IQR, 2.87–6.46 years) for the preexist-
ing DSA ABMR group and 3.49 years
(IQR, 1.48– 5.54 years) for the de novo
DSA ABMR group (P=0.0 01).
There was no difference in renal func-
tion between groups at the time of ABMR
diagnosis but de novo DSA ABMR presen-
ted with more proteinuria (1.5162.51 g/g
creatini ne versus 0 .5161.05 g/g creati-
nine; P,0.001). More preexisting anti-
HLA DSA ABMR were subclinical
(n=23, 22.3%) compared with de novo
anti-HLA DSA ABMR (n=9, 8.8%) but
there was no difference in terms of eGFR
at the time of the biopsy (eGFR, 39.006
18.26 ml/min per 1.73 m
2
in the preexist-
ing anti-HLA DSA group versus 41.656
21.19 ml/min per 1.73 m
2
in the de novo
anti-HLA DSA group; P=0.34).
At the time of transplantation, pa-
tients w ith preexisting DSA ABMR re-
ceived more thymoglobulin (n=70,
Table 1. Characteristics of patients with ABMR according to two types: preexisting DSA and de novo DSA
Charact eristics
All Patients
Preexisting Anti-HLA
DSA ABMR
De Novo Anti-HLA
DSA ABMR
P Value
nn=205 nn=103 nn=102
Recipient
Age, yr, mea n (SD) 205 47.16 (15.39) 103 47.75 (1 3.00) 102 46.56 (17 .52) 0.53
Men, n (%) 205 118 (57.56) 103 46 (44.66) 102 72 (70.59) ,0.001
ESRD causes, n (%) 205 103 102
Glomerulonephritis 75 (36.59) 28 (27.18) 47 (46.08)
Diabete s 16 (7.80) 6 (5.83) 10 (9.80)
Polycys tic kidney disease 10 (4.88) 3 (2.91) 7 (6.86)
Tubulo-interstitial disease 29 (14.15) 24 (23.30) 5 (4.90)
Hypertension 14 (6.83) 7 (6.80) 7 (6.86)
Unknown 43 (20.97) 29 (28.16) 14 (13.73)
Other 18 (8.78) 6 (5.82) 12 (11.77) ,0.001
Donor
Age, yr, mea n (SD) 203 45.57 (17.15) 103 48.06 (1 4.56) 100 43.01 (19 .20) 0.04
Men, n (%) 203 109 (53.69) 103 57 (55.34) 100 52 (52.00) 0. 37
DD, n (%) 204 158 (77.45) 103 93 (90.29) 101 65 (64.36) ,0.001
Immunology at the time of transplant
HLA class of anti-HLA DSA, n 103 103
Immunodominant class 1 49 49 —
Immunodominant class 2 54 54 —
DSA MFI, median [IQR] 4500 [1862–10,210] 4500 [1862–10,210] —
Treatment at the time of transplant, n (%)
Steroids 205 194 (94.63) 103 103 (100) 102 91 (89.22) ,0.001
Thymoglobulin 205 111 (54.15) 103 70 (67.96) 102 41 (40.20) ,0.001
Plasmapheresis 205 18 (8.78) 103 18 (17.48) 102 0 ,0.001
Anti-CD20 therapy 205 20 (9.76) 103 20 (19.42) 102 0 ,0.001
IVIG 205 69 (33.66) 103 61 (59.22) 102 8 (7.84) ,0.001
Baseline immunosuppression, n (%) 205 103 102
Tacrolimus 131 (63.90) 89 (86.4 1) 42 (41.18) ,0.001
Cyclosporin 70 (34.15) 15 (14.56) 55 (53.92) ,0.001
Sirolimus 2 (0.98) 0 2 (1.96) 0.25
Follow-up, yr, mean (SD) 205 4.13 (2.52) 103 4.71 (2.42) 102 3.55 (2.50) 0.001
Graft loss, n (%) 205 86 (41.95) 103 30 (29.13) 102 56 (54.90) ,0.001
—, patients in the de novo DSA ABMR have no DSA at the time of transplant; MFI, mean fluorescence intensity.
1914 Journal of the American Society of Nephrology J Am Soc Nephrol 28: 1912–1923, 2017
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Figure 2. Preexisting DSA ABMR and de novo DSA ABMR landscapes . (A) Expression of preexisting DSA ABMR transcripts in kidney
allografts. (B) Expression of de novo DSA ABMR transcripts in kidney allografts. Dots represent individual probe sets on the microarray.
The associ ation strength (x-axis) is compared with fold change (y -axis) defined by ABMR v ersus all other biopsies of the control set (i.e.,
without ABMR). NK, nat ural killer cell.
J Am Soc Nephrol 28: 1912–1923, 2017 Preexisting versus De Novo DSA 1915
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CLINICAL RESEARCH
68.0%), plasmapheresis (n=18, 17.5%),
anti-CD20 therapy (n=20, 19.4%), an d
intravenous Ig (IVIG) (n=6 1, 59. 2%)
compared w ith patients with de novo
DSA ABMR (P,0.001 for all compari-
sons) (Table 1). At the time of ABMR
biopsy, patients w ith preexisting DSA
ABMR receive d m ore ste roid s ( n=81,
78.6%) and more plasmapheresis
(n=63, 61.2%) compared with patients
with de n ovo DSA A BMR (n=39, 38.2%
and n=28, 26.9%, respectively; P,0.001
for both). There was no d ifference in the
use of anti-CD20 therapy or IVIG
(P=0.18 and P=0.42, respectively) (Sup-
plemental Table 1).
Anti-HLA DSA Characteristics at the
Time of Transplantation and at the
Time of ABMR
At the time of transplantation, the median
DSA mean fluoresc ence intensity max in
preexisting DSA ABMR was 4500 (IQR,
1862–10,210). The immunodominant
DSA was class 1 for 49 patients (47.6%)
and class 2 for 54 patients (52.4%).
At the time of ABMR, the immunodo-
minant DSA in preexisting DSA ABMR
was class 1 for 40 patients (38.8%) and
class 2 for 63 patients (61.2%), with a
median mean fluorescence intensity
(MFI) of 2561 (IQR, 1252–6937). In de
novo DSA ABMR, the immunodominant
DSA was class 1 for 26 patients (25.5%)
and class 2 for 76 patients (74.5%), with a
higher median MFI of 7295 (IQR, 1948–
11,814; P,0.001).
Biopsy Lesions According to
Preexisting versus De Novo
DSA-Related ABMR
Table 2 depicts the kidney histology at the
time of diagnosis. ABMR in preexisting
DSA ABMR presented with mor e glomer -
ulitis (g score: 1.7161.02 versus 1.066
0.91; P,0.001) compared with de novo
DSA ABMR. ABMR in de novo DSA
ABMR presented with more double con-
tours (cg score: 1.2861.15, n=64 of 102
versus 0.4860.94, n=26 of 103; P,0.001),
more tubulitis (t score: 1.0161.11 versus
0.596 0.90; P=0.003), more atrophy
fibrosis (ci score: 1.606 0.92 versus
0.9661.04; P,0.001; ct scor e: 1.6060.91
versus 0.9960.99; P,0 .001) and more ar -
teriolar hyalinosis (ah score: 1.5361.05
versus 0.9760.92; P,0.001). There were
no significant differences in peritubular
capillary inflammation (ptc score: 1.766
0.98 in preexisting D SA ABMR versus
1.666 1.00 in de novo DSA ABMR;
P=0.47), C4d deposition in the peritubular
capillaries (51% positive C4d deposition
in preexisting DSA ABMR versus 42% in
de novo DSA ABMR; P=0.13), endarteritis
(v score: 0.3260.65 in preexisting DSA
ABMR versus 0.2260.60 in de novo DSA
ABMR; P=0.29), or fibrous intimal thick-
ening and arteriosclerosis (cv sco re: 1.266
1.00 in preexisting DSA ABMR versus
1.4460.98 in de novo
DSA ABMR; P=0.2).
Biopsy Gene Expression According
to Preexisting versus De novo DSA
ABMR
We first compared the global transcript
changes in ABMR w ith preexisting anti-
HLA DSA ABMR or de novo anti-HLA
DSA ABMR versus all other biopsies in
the control set ( i.e., without ABMR),
plotting fold change and ABMR associ-
atio n strength (P value) .
Figure 2A shows the top transcripts as-
sociated with preexisting anti-HLA DSA
ABMR. The transcripts mostly associated
with preexisting anti-HLA ABMR were:
(1) natural killer cell–selective transcripts
CCL4, KLRD1, SH2D1B, CD160,
and NCR1; (2) endothelial and IFNg-
inducible genes including chemokines
Table 2. Histology, DSA, and renal function at the time of ABMR-proven biopsy
Parameters
Preexisting Anti-HLA
DSA ABMR (n=103)
De Novo Anti-HLA
DSA ABMR (n=102)
P Value
Histology
g(0–3), mean (SD) 1.71 (1.02) 1.06 (0.91) ,0.001
ptc (0–3), mean (SD) 1.76 (0.98) 1.66 (1.00) 0.47
C4d positive, n (%) 53 (51.46 ) 39 (42.39) 0.13
cg (0–3), mean (SD) 0.48 (0.94) 1.28 (1.15) ,0.001
i(0–3), mean (SD) 0.61 (0.92) 1.23 (1.01) ,0.001
t(0–3), mean (SD) 0.59 (0.90) 1.01 (1.11) 0.003
v(0–3), mean (SD) 0.32 (0.65) 0.22 (0.60) 0.29
ci (0–3), mean (SD) 0.96 (1.04) 1.60 (0.92) ,0.001
ct (0–3), mean (SD) 0.99 (0.99) 1.60 (0.91) ,0.001
cv (0–3), mean (SD) 1.26 (1.00) 1.44 (0.98) 0.2
ah (0–3), mean (SD) 0.97 (0.92) 1.53 (1.05) ,0.001
Immunology at the time of the ABMR biopsy
Anti-HLA DSA class 1, n (%) 40 (38.83 ) 26 (25.49)
Anti-HLA DSA class 2, n (%) 63 (61.17 ) 76 (74.51) 0.02
Anti-HLA DSA MFI, median [IQR] 2561 [1252–6937] 7295 [1948–11,814] ,0.001
Renal function
eGFR, ml/min per 1.73 m
2
, mean (SD) 39.00618.26 41.65621.19 0.34
Proteinuria, g/g creatinine, mean (SD) 0.5161.05 1.5162.51 ,0.001
g, glomerulitis; ptc, peritu bular capillaritis; cg, transplant glomerulopathy; i, interstitial inflammation; t, tubulitis ; v, endarteritis; ci, in terstitial fibrosis; ct, tubu lar
atrophy; cv, arteriosclerosis; ah, arteriolar hyaline thickening; MFI, m ean fluorescence intensity.
1916 Journal of the American Society of Nephrology J Am Soc Nephrol 28: 1912–1923, 2017
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