Donor-Derived CD4+ T Cells and Human Herpesvirus 6B Detection After Allogeneic Hematopoietic Cell Transplantation

We sought to determine whether donor-derived human herpesvirus (HHV) 6B-specific CD4(+) T-cell abundance is correlated with HHV-6B detection after allogeneic hematopoietic cell transplantation. We identified 33 patients who received HLA-matched, non-T-cell-depleted, myeloablative allogeneic hematopoietic cell transplantation and underwent weekly plasma polymerase chain reaction testing for HHV-6B for 100 days thereafter. We tested donor peripheral blood mononuclear cells for HHV-6B-specific CD4(+) T cells. Patients with HHV-6B detection above the median peak viral load (200 copies/mL) received approximately 10-fold fewer donor-derived total or HHV-6B-specific CD4(+) T cells than those with peak HHV-6B detection at <= 200 copies/mL or with no HHV-6B detection. These data suggest the importance of donor-derived immunity for controlling HHV-6B reactivation.

Automated summary

This study aimed to determine the correlation between donor-derived HHV-6B-specific CD4(+) T-cell abundance and HHV-6B detection post allogeneic hematopoietic cell transplantation. The findings suggest that donor-derived immunity plays a critical role in controlling HHV-6B reactivation among transplant recipients.