Quantification of Torque Teno Virus and Epstein-Barr Virus Is of Limited Value for Predicting the Net State of Immunosuppression After Lung Transplantation

Nordén, Rickard; Magnusson, Jesper; Lundin, Anna; Tang, Ka-Wei; Nilsson, Staffan; Lindh, Magnus; Andersson, Lars-Magnus; Riise, Gerdt C; Westin, Johan

We found that TTV-DNA levels increased rapidly; 1 month after LTx, the levels were already markedly elevated, presumably due to ablation of the functional effector cells of the immune system that normally control the TTV infection [14, 15] . At 3 months post-LTx, the mean TTV-DNA level peaked and then gradually declined, reflecting the gradual moderation of immunosuppressive therapy. Interestingly, the TTV-DNA level was lower in patients who received Cyclosporine treatment, possibly mirroring a different immune modulatory mechanism for Cyclosporine compared with Tacrolimus. Görzer et al. [16] previously suggested that this might be due to Cyclosporine being less efficient as an immunosuppressant. However, we found no association between type of immunosuppressive regimen and acute rejection or other events that would indicate a difference in net immunosuppressive effect. Recently, TTV-DNA has been associated with chronic lung allograft dysfunction after lung transplantation [29] , but in our study this was not included as an outcome.