Significance of Epstein-Barr virus DNA quantitation in donors of hematopoietic stem cell transplantation

Background : Epstein-Barr virus (EBV) is a well-known causative agent of various diseases including post-transplant lymphoproliferative disorders. Although the level of EBV viral load in donors is expected to have a direct effect on recipients after hematopoietic stem cell transplantation (HSCT), little has been studied providing a clear evidence for that. We performed EBV DNA quantitation in donors and analyzed the effect of donors' EBV viral load on the recipients after HSCT. Methods : EBV DNA quantitation of peripheral blood in 94 healthy HSCT donors was performed by real-time PCR. We analyzed the distribution of EBV viral load in HSCT donors and EBV positivity in the recipients transplanted from donors who had detectable EBV. Results : Fifteen HSCT donors (16%) showed positive results in EBV real-time quantitative PCR. EBV viral load was below 500 copies/mL in 5 donors and above 500 (680-11,300) copies/mL in 10 donors. Rve of the recipients (33.3%) transplanted from these 15 donors showed positivity in EBV PCR after HSCT. All of the EBV PCR positive recipients were transplanted from donors with viral load of > 1,000 copies/mL, and 5 (71%) of 7 donors with viral load of > 1,000 copies/mL was associated with posttansplant EBV PCR positivity in the recipients. Conclusions : Higher levels of EBV viral load in donors appear to be associated with EBV transmission to recipients in HSCT. EBV real-time quantitative PCR may be needed for screening EBV DNA level in HSCT donors.