Kidney Week

Abstract: FR-PO905

BKV Clearance Time Correlates with the Exhaustion State and T-Cell Receptor Repertoire Shape of BKV-Specific T-Cells in Renal Transplant Patients with Severe BKV Infection

Session Information

• Transplantation: Translational and Transplant Pathology
  October 26, 2018 | Location: Exhibit Hall, San Diego Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Transplantation

• 1802 Transplantation: Clinical

Authors

• Stervbo, Ulrik, University Hospital Marien Hospital Herne, Herne, Germany

Ulrik Stervbo,

• Nienen, Mikalai, University Hospital Marien Hospital Herne, Herne, Germany

Mikalai Nienen,

• Reinke, Petra, Charité, Campus Virchow Klinikum, Berlin, Germany

Petra Reinke,

• Westhoff, Timm H., University Hospital Marien Hospital Herne, Herne, Germany

Timm H. Westhoff,

• Babel, Nina, University Hospital Marien Hospital Herne, Herne, Germany

Nina Babel,

Background

Reactivation of the BK polyomavirus is known to lead to severe complications in kidney transplant patients. The current treatment strategy relies on decreasing the immunosuppression to allow the immune system to clear the virus. Recently we demonstrated a clear association between the resolution of BKV reactivation and reconstitution of BKV-specific CD4+ T-cells. However, the factors determining the duration of the clearance of the viral infection remain unknown.

Methods

Here we apply a combination of in-depth multiparametric flow cytometry and CDR3 beta chain receptor repertoire analysis of BKV specific T-cells to a cohort of 5 kidney transplant patients with BKV reactivation. In this manner we were able to track the TCR repertoires at single clone levels during the clinical course of BKV infection.

Results

The number of BKV-specific T-cells in peripheral blood did not affect the duration of BKV infection. In contrast, the diversity of the T-cell receptor repertoire as well as exhaustion status of BKV-specific T-cells correlated with the duration of viral clearance. This duration was further found to be independent of hyperexpanded, immunodominant BKV-specific T-cell clones and of the overall magnitude of cellular immunity. Rather, the diversity of BKV-specific TCR repertoire in peripheral blood: high diversity of the repertoire and lack of PD1 and TIM-3 exhaustion markers on BKV-specific T-cells is associated with short remission time.

Conclusion

Our data demonstrate that the quality (exhaustion status and shape of the repertoire) rather than quantity of BKV-specific T-cells determines the remission time after BKV reactivation.

Funding

• NIDDK Support