Allogeneic virus-specific T cells with HLA alloreactivity do not produce GVHD

memory T cells can reconstitute antiviral immunity, but in a recent report a majority of virus-specific cytotoxic T-lymphocyte (CTL) lines showed in vitro cross-reactivity against allo-human leukocyte antigen (HLA) mol-ecules as measured by interferon- secre-tion. We therefore reviewed our clinical expe-rience with adoptive transfer of allogeneic hematopoietic stem cell transplantation donor-derived virus-specific CTLs in 153 re-cipients, including 73 instances where there was an HLA mismatch. There was no de novo acute graft-versus-host disease after infusion, and incidence of graft-versus-host disease reactivation was low and not signifi-cantly different in recipients of matched or mismatched CTL. However, we found that virus-specific T cell lines recognized up to 10 % of a panel of 44 HLA disparate targets, indicating that virus-specific T cells can have cross-reactivity with HLA-mismatched targets in vitro. These data indicate that the adoptive transfer of partially HLA-mismatched virus-specific CTL is safe de-spite in vitro recognition of recipient HLA molecules. (Blood. 2010;116(22):4700-4702