Torque Teno Virus DNA plasma level reflects immunosuppression in lung transplant recipients and might help to predict rejection

Lung transplantation is the only therapeutic option in end stage lung diseases, however, survival after transplantation is limited by acute and chronic rejections and infections being a result of inappropriate immunosuppression. Torque Teno Viruses (TTV) are ubiquitous DNA viruses in humans but not found to be causative for any disease. However, some reports suggest that TTV DNA levels reflect the grade of immunosuppression with higher levels being found in more immunosuppressed individuals.

We investigated the TTVD DNA levels in 34 lung transplant recipients within their first year. In accordance with previous results TTV DNA levels increase after lung transplantation reaching a steady state after 3 months. TTV DNA levels were not correlated with immunosuppressive trough levels.In steady state TTV DNA levels were significantly higher in patients with infectious complications compared to the group of patients without. Additionally, TTV DNA levels decreased significantly prior to biopsy-proven rejection. Sensitivity of a tenfold decrease in TTV DNA levels for a subsequent rejection episode was 0.74 with a specificity of 0.99.

In summary TTV DNA might be used as an additional tool to monitor immunosuppression in lung transplant recipients.