Long-term allograft acceptance in a patient with posttransplant lymphoproliferative disorder: correlation with intragraft viral interleukin-10.

BACKGROUND

Viral (v) interleukin (IL)-10 is expressed by Epstein-Barr virus (EBV) and has pro- and anti-inflammatory actions similar to human IL-10. EBV is also a known factor in the development of posttransplant lymphoproliferative disorder (PTLPD) in allograft recipients. We observed a patient with widespread PTLPD 9 months after renal transplantation, who subsequently maintained renal function despite minimal immunosuppression, and we investigated a possible link between these factors.

METHODS

The patient's chart was reviewed for relevant history. EBV DNA in blood and tissues was assessed by polymerase chain reaction. Human and vIL-10 and gamma-interferon mRNA were evaluated with reverse transcription-polymerase chain reaction using nested primers.

RESULTS

After the diagnosis of PTLPD, the patient was maintained on prednisone (8 mg/day) as the only immunosuppression with preserved renal function for 17 months until death as a result of pulmonary failure. She had continuously high blood levels of EBV DNA, although only mild persistent intrarenal atypical lymphocytic infiltrates. Human IL-10 mRNA was never present; in contrast, intragraft vIL-10 mRNA was identified and associated with resolution of an intervening episode of severe acute transplant rejection.

CONCLUSIONS

We suggest that the preserved renal function resulted from the anti-inflammatory actions of vIL-10 inhibiting acute rejection in the renal allograft.