Table 1.
Selected biomarkers for outcomes in kidney transplantation: summary of current status
| Authors | Assay Name | Assay Type | Timing Post-Transplant | Outcome | Discovery Set: Se/sp/ppv/npv | Validation Set: Se/sp/ppv/npv | Training/Test Sample | Biomarker Lifecycle |
|---|---|---|---|---|---|---|---|---|
| FDA-approved assays | ||||||||
| Patel and Terasaki19 | CDC crossmatch | Microcytotoxicity assay | Pretransplant | Hyper-AR/early graft loss | 0.75/0.97/0.80/0.97 | Not applicable, no validation set | 225 | FDAA: Y; Comm: Y |
| Mahoney et al.149 | Flow crossmatch | Flow cytometry | Pretransplant | Early graft loss (<2 mo) | 0.71/0.74/0.33/0.93 | Not applicable, no validation set | 90 | FDAA: Y; Comm: Y |
| Pei et al.150 | Lumine | HLA beads; flow cytometry | Variable pre-/post-transplant | Anti-HLA Ab | Details not available in manuscript | Not applicable, no validation set | 10 | FDAA: Y; Comm: Ya |
| Ashokkumar et al.61 | Pleximmune | T cytotoxic memory cell assay | Rejection episodes | Biopsy-proven AR | 0.88/0.94/0.93/0.88 | 1.0/0.86/0.80/1.0 | 32/11 | FDAA: Y; Comm: Y |
| He et al.63 | Cylex-Immuknow | Lymphocyte ATP generation assay | Serial <30 mo | CD4-T cell function | Details not available in manuscript | Not applicable, no validation set | 42 | FDAA: Y; Comm: Y |
| Loupy et ald.32 | C1q binding assay | Flow cytometric C1q bindingb | Baseline, 1 yr, rejection episode | TCMR/ABMR/graft loss | Details not available in manuscript | Not applicable, no validation set | 1016 | FDAA: Y; Comm: Yb |
| Selected externally validated assays in kidney transplantation (pending FDA approval) | ||||||||
| Hricik et al.47 | IFN-γ ELISPOT | Donor-reactive memory T cell | Preatransplant | De novo DSA and/or rejection | 1.0/0.67/0.67/1.0 | Not applicable, no validation set | 21 | FDAA: N; Comm: N |
| Hricik et al.70 | Urine CXCL9 | Urine ELISA | Serial <6 mo, rejection episode | TCMR | 0.85/0.81/0.68/0.92 | Not applicable, no validation set | 258 | FDAA: N; Comm: N |
| Suthanthiran et al.86 | Urine three-gene signature | Urinary RNA by qPCR | Serial <12 mo, rejection episode | AR | Details not available in manuscript | Details not available in manuscript | 485 (4300 urine samples) | FDAA: N; Comm: N |
| Roedder et al.119 | KSORT | Peripheral blood RNA by qPCR | Serial <24 mo, rejection episode | Biopsy-proven AR | 0.83/0.91/0.81/0.91 | 0.91/0.99/0.95/0.98 | 143/124 | FDAA: N; Comm: N |
| Halloran et al.112 | ENDAT | Graft biopsy RNA by microarray | Variable (1 wk to 31 yr) | ABMR | 0.69/0.85/0.50/0.94 | 0.67/0.90/0.64/0.91 | 300/403 | FDAA: N; Comm: N |
| O’Connell et al.18 | GoCAR score | Graft biopsy RNA by microarray (3-mo protocol biopsies) | 3 mo biopsy | Prediction of fibrosis/histologic progression | 0.93/0.95/0.93/0.95 | 0.67/0.92/0.86/0.81 | 159/45 | FDAA: N; Comm: N |
Se, sensitivity; sp, specificity; ppv, positive predictive value; npv, negative predictive value; CDC, complement dependent cytotoxicity; FDAA, US FDA approved; Y, yes; Comm, commercialized assay available; TCMR, T cell–mediated rejection (Banff ≥1A); N, no; KSORT, kidney solid organ response test; ENDAT, endothelial-associated transcripts; GoCAR, Genomics of Chronic Allograft Rejection.
a
Assay approved for detection of DSAs (not for quantification).
b
C1q binding Bindazyme assay is FDA approved, but flow cytometric C1qScreen (One-Lambda) used in this study is not FDA approved.