Haploidentical stem cell transplantation is an attractive form of alternative donor transplantation because of the immediate donor availability, ease of stem cell procurement, and the possibility to collect donor cells for further cellular therapy. T-cell depleted haploidentical transplantation (the Perugia approach) has been limited by a high nonrelapse mortality related to infectious complications as a result of delayed immune reconstitution posttransplantation. Research in this field is focusing on improving immune reconstitution by immunotherapy with different types of T-cells that do not cause graft-versus-host disease. A more recent modality (Hopkins approach), resulting in a decreased risk of graft-versus-host disease, is the use of T-cell replete haploidentical stem cells in combination with posttransplantation high-dose cyclophosphamide to eliminate expanding alloreactive T-cells. Research with this approach is focusing on the prevention of disease relapse posttransplantation. It seems that the most important barriers against successful haploidentical transplantation can now be overcome. This review evaluates the opposing modalities (T-cell replete versus T-cell depleted approach) and future directions of haploidentical stem cell transplantation in adults.

(BELG J HEMATOL 2012;3:74–81)