Donor Lymphocyte Infusion After Allogeneic Hematopoietic Stem Cell Transplantation

Abstract

Donor lymphocyte infusion, a rescue therapy after hematopoietic stem cell transplantation, has been increasingly adopted, as modalities of stem cell transplantation have widened. First described as donor lymphocyte transfusion or cell therapy, it consists of infusion of donor lymphocytes, collected in steady state or after growth factor enhancement. As in literature the most used name is donor lymphocyte infusion, we'll adopt it here. Its most striking efficacy is observed in patients with chronic myelogenous leukemia, who relapsed after allogeneic stem cells transplantation. However, graft-versus-host disease, its main complication, may still hamper its feasibility. KEYWORDSAllogeneic hematopoietic stem cell transplantation (HSCT) has become an attractive approach for the treatment of many patients with hematological diseases, including malignant and nonmalignant disorders. Importantly, in the last 15 years, with the advent of reduced intensity conditioning (RIC) regimens, many older adult patients, initially excluded from this therapy approach, became eligible for HSCT. This approach decreased the transplant-related mortality, still maintaining T-cell immune response from the graft against the host tumor cells, also known as the graft-versus tumor or graft Practice points• Donor lymphocyte infusion (DLI) is an alternative strategy to reverse mixed chimerism, treat relapse and reconstitute immunity against infections after hematopoietic stem cell transplantation.• Responses to DLI are disease-dependent.• As main side effect, DLI can promote graft-versus-host disease (GVHD) in the range of 40-60% of patients.• The incidence of GVHD after unrelated DLI is similar to the incidence after related DLI, both presenting same pattern of presentation.• Although GVHD and graft versus leukemia (GVL) after DLI are highly correlated, some patients experience remission (GVL) without expressing GVHD.• Escalating doses for DLI is preferable, as it induces less GVHD. There is no clear association, yet confirmed, between T-cell dose and incidence of neither GVHD nor GVL after DLI.• The further DLI is made from transplantation, the better outcome.• Preadjuvant treatment before DLI is preferable as DLI effect is enhanced with low tumor burden.• Some strategies still under investigation are focused on separating GVHD and GVL, including graft engineering and gene therapy, to improve clinical outcome.For reprint orders, please contact: reprints@futuremedicine.com