Long-Term Follow-Up after Adoptive Transfer of BK-Virus-Specific T Cells in Hematopoietic Stem Cell Transplant Recipients

Abstract

The BK virus (BKV) causes severe hemorrhagic cystitis in hematopoietic stem cell transplant (HSCT) recipients. To eliminate reactivated BKV, symptomatic patients can be treated with a reduction of the immunosuppressive therapy, with the antiviral drug cidofovir, or with virus-specific T cells (VSTs). In the current study, we compared the effect of VSTs to other treatment options, following up specific T cells using interferon-gamma ELISpot assay. We observed BKV large T-specific cellular responses in 12 out of 17 HSCT recipients with BKV-related cystitis (71%). In recipients treated with VSTs, 6 out of 7 showed specific T-cell responses, and that number in those without VSTs was 6 out of 10. In comparison, 27 out of 50 healthy controls (54%) responded. In HSCT recipients treated for BKV-related cystitis, absolute CD4+ T-cell numbers and renal function correlated with BKV-specific cellular responses (p = 0.03 and 0.01, respectively). In one patient, BKV-specific cellular immunity could already be detected at baseline, on day 35 after HSCT and prior to VSTs, and remained increased until day 226 after VSTs (78 vs. 7 spots increment). In conclusion, the ELISpot appears to be suitable to sensitively monitor BKV-specific cellular immunity in HSCT recipients, even early after transplantation or in the long term after VSTs.

Development and characterization of a cell donor registry for virus‐specific T cell manufacture in a blood bank

“…Also, it has been reported that T cell response is crucial for the resolution of BKV infection and that treatment with BK VST cells is safe and potentially effective. [45][46][47][48][49][50] According to our experience, there is a growing interest in treating BK infection after kidney transplantation with BK VST cells. In this particular context, autologous therapy has some important limitations, such as the lack of donor availability in cadaveric organ transplantation and the low number of shared HLA alleles between the patient and the graft donor.…”