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APPENDIX S1

Derivation of the Propensity Matched Control Cohort

The outcome for the analysis was defined as eGFR at 6-months and 1-year post conversion. eGFR > 120 were assigned a value of 120, and eGFR < 8 were assigned a value of 8. We tested for 1:1, 1:2 and 1:3 ratio matching (ratio beyond = quality of the matching not acceptable), with the following parameters to match on: -Degree of Interstitial fibrosis/tubular atrophy (IFTA) at index biopsy -Microvascular Inflammation (PTC+G) at index biopsy -eGFR at inclusion -Proteinuria at inclusion (g/g) -Donor age -Donor type (living donor/cadaveric) -DGF -DSA at inclusion (yes/no) -Retransplantation -Recipient sex -Recipient age

Based upon the propensity score histograms (Figures detailed below) we decided to use the 1:2 ratio as the best for further analyses.

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Ratio 1:1:

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Ratio 1:2

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Ratio 1:3

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APPENDIX S2 Figure S1: Individual Estimated Glomerular Filtration Rate Trend

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APPENDIX S3 Individual Expression Pre and Postconversion biopsies

Pre Post P-

SYMBOL GENE Biopsy Biopsy value

PARP10 poly (ADP-ribose) polymerase family, member 10 199 164 0.09

ACPP acid phosphatase, prostate 68 136 0.11

TRIM63 tripartite motif containing 63, E3 ubiquitin protein ligase 47 38 0.23

ACPP acid phosphatase, prostate 134 347 0.24

ACPP acid phosphatase, prostate 60 145 0.29

BIRC5 baculoviral IAP repeat containing 5 37 30 0.29

PCDHB13 protocadherin beta 13 30 37 0.29

F2 coagulation factor II (thrombin) 35 29 0.29

FSD1 fibronectin type III and SPRY domain containing 1 99 84 0.33

PTTG1 pituitary tumor-transforming 1 70 58 0.33

IFNA5 interferon, alpha 5 10 9 0.33

BIRC5 baculoviral IAP repeat containing 5 38 32 0.33

FGFR3 fibroblast growth factor receptor 3 86 74 0.33

SSU72 RNA polymerase II CTD phosphatase homolog (S. 213 182 0.35 SSU72 cerevisiae)

NARFL nuclear prelamin A recognition factor-like 122 105 0.36

SPRED2 sprouty-related, EVH1 domain containing 2 321 370 0.40

MAVS mitochondrial antiviral signaling protein 46 39 0.40

BCL2L1 BCL2-like 1 42 34 0.45

NARG2 NMDA receptor regulated 2 92 108 0.50

GPER G protein-coupled estrogen receptor 1 221 187 0.50

CLUH clustered mitochondria (cluA 86 73 0.50

ADAM15 ADAM metallopeptidase domain 15 104 85 0.50

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Pre Post P-

SYMBOL GENE Biopsy Biopsy value

USP36 ubiquitin specific peptidase 36 115 136 0.50

CLSTN3 calsyntenin 3 113 97 0.50

TRABD TraB domain containing 129 111 0.50

CLCN7 chloride channel, voltage-sensitive 7 86 67 0.50

MYRIP myosin VIIA and Rab interacting protein 29 41 0.50

REXO4 REX4, RNA exonuclease 4 homolog (S. cerevisiae) 56 44 0.50

GIMAP6 GTPase, IMAP family member 6 68 56 0.50

OGFR opioid growth factor receptor 138 112 0.50

REXO4 REX4, RNA exonuclease 4 homolog (S. cerevisiae) 56 44 0.50

DNM1P35 DNM1 pseudogene 35 16 13 0.50

ARHGAP1 Rho GTPase activating protein 1 84 71 0.50

CDAN1 codanin 1 57 49 0.50

NT5C1A 5'-nucleotidase, cytosolic IA 21 18 0.50

DEF8 differentially expressed in FDCP 8 homolog (mouse) 138 123 0.50

ABCC6 ATP-binding cassette, sub-family C (CFTR 66 55 0.50

CACNA1E calcium channel, voltage-dependent, R type, alpha 1E subunit 17 14 0.50

SCML1 sex comb on midleg-like 1 (Drosophila) 149 189 0.50

GSDMC gasdermin C 56 48 0.50

PCDHGA1 protocadherin gamma subfamily A, 1 968 1153 0.50

PPP6R1 protein phosphatase 6, regulatory subunit 1 320 283 0.50

GORASP1 golgi reassembly stacking protein 1, 65kDa 21 17 0.50

DHCR24 24-dehydrocholesterol reductase 62 52 0.50

S1PR3 sphingosine-1-phosphate receptor 3 188 307 0.50

CYTH1 cytohesin 1 59 49 0.50

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Pre Post P-

SYMBOL GENE Biopsy Biopsy value

inhibitor of kappa light polypeptide gene enhancer in B-cells, 46 38 0.50 IKBKE kinase epsilon

PRRC2B proline-rich coiled-coil 2B 109 88 0.50

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