Kidney Week

Abstract: TH-OR125

Kidney Recipient-Donor KIR-HLA Ligand Mismatch Is Associated with Reduced Graft Survival

Session Information

• Predictors of Clinical Outcomes After Kidney Transplantation
  October 25, 2018 | Location: 6C, San Diego Convention Center
  Abstract Time: 05:18 PM - 05:30 PM

Category: Transplantation

• 1802 Transplantation: Clinical

Authors

• Heinzel, Andreas, Medical University of Vienna, Vienna, Vienna, Austria

Andreas Heinzel

• Kregar, Lori Dolores, Medical University of Vienna, Vienna, Vienna, Austria

Lori Dolores Kregar,

• Reindl-Schwaighofer, Roman, Medical University of Vienna, Vienna, Vienna, Austria

Roman Reindl-Schwaighofer,

• Kainz, Alexander, Medical University of Vienna, Vienna, Vienna, Austria

Alexander Kainz,

• Jelencsics, Kira, Medical University of Vienna, Vienna, Vienna, Austria

Kira Jelencsics,

• Hu, Karin, Medical University of Vienna, Vienna, Vienna, Austria

Karin Hu,

• Hruba, Petra, Institute for Clinical and Experimental Medicine, Department of Nephrology, Prague, Czechia

Petra Hruba,

• Viklicky, Ondrej, Institute for Clinical and Experimental Medicine, Department of Nephrology, Prague, Czechia

Ondrej Viklicky,

• Bohmig, Georg, Medical University of Vienna, Vienna, Vienna, Austria

Georg Bohmig,

• Keating, Brendan, University of Pennsylvania, Philadelphia, Pennsylvania, United States

Brendan Keating,

• Oberbauer, Rainer, Medical University of Vienna, Vienna, Vienna, Austria

Rainer Oberbauer,

Background

Differences in KIRs between recipients can lead to different KIR-HLA ligand constellations not captured by HLA matching alone. These differences may contribute to variation in allogeneic response to the renal allograft after transplantation.

Methods

We made use of the iGeneTrain consortium and genotyped 162 first kidney transplant recipients and respective HLA-DR matched deceased donors from two centers in Vienna and Prague. KIR types were imputed using KIR*IMP. HLA eplet mismatch was calculated for the HLA-A, -B, -C, -DP, -DQ, and -DR loci.

The median follow-up time of the cohort was 5.8 years. KIR HLA ligand mismatches were defined based on the presence of inhibitory KIRs (2DL1, 2DL2, 2DL3 and 3DL1) and activating KIRs (2DS1 and 2DS2) in the recipient and absence or presence of the corresponding ligand in the donor, respectively. Kaplan-Meier analysis and a Cox PH model were used to assess the association of KIR-HLA ligand mismatch with death censored graft loss.

Results

Comparison of the groups of recipients with no- and at least a single KIR-HLA ligand mismatch revealed an elevated risk for graft loss following renal transplantation in the latter group (see figure 1). This association remained significant in a multivariable Cox model after adjustment for full HLA eplet mismatch and donor age (HR: 3.01 CI: 1.06 – 8.56, p-value: 0.039).

Conclusion

Presence of a KIR-HLA ligand mismatch between recipient and donor is associated with graft loss after HLA-DR matched kidney transplantation.

Figure 1: Kaplan-Meier survival curves comparing HLA-DR matched kidney recipient-donor pairs without and with a KIR-HLA ligand mismatch.