• kidney transplantation
• liver transplantation
• pancreas transplantation
• solid organ transplantation
• Torquetenovirus

Torquetenovirus (TTV) is a human anellovirus first discovered in 1997, and currently orphan from pathologies. We attempted to corroborate its use as a marker of functional immunosuppression in solid organ transplantation (SOT).
We selected two cohorts for different evaluations: kidney/pancreas transplant recipients for evaluation of induction immunosuppression, and orthotopic liver transplant recipients for evaluation of maintenance immunosuppression.
Our results confirm TTV as a T lymphocytotropic virus. TTV viremia serves as cheap surrogate of functional immune competence in SOT and kinetics is independent of allograft type. Short-term kinetics is driven by the type of induction immunosuppression, while long-term kinetics is driven by type and plasma level of maintenance immunosuppression.
TTV viremia is a good marker of iatrogenic immunosuppression and could be used to tailor-made maintenance immunosuppression.