Haploidentical Hematopoietic Stem-Cell Transplantation in Adults

Haploidentical hematopoietic stem-cell transplantation is an alternative transplant strategy for patients without an HLA-matched donor. Still, only half of patients who might benefit from transplantation are able to find an HLA-matched related or unrelated donor. Haploidentical donor is readily available for many patients in need of immediate stem-cell transplantation. Historical experience with haploidentical stem-cell transplantation has been characterised by a high rejection rate, graft-versus-host disease, and transplant-related mortality. Important advances have been made in this field during the last 20 years. Many drawbacks of haploidentical transplants such as graft failure and significant GVHD have been overcome due to the development of new extensive T cell depletion methods with mega dose stem-cell administration. However, prolonged immune deficiency and an increased relapse rate remain unresolved problems of T cell depletion. New approaches such as partial ex vivo or in vivo alloreactive T cell depletion and posttransplant cell therapy will allow to improve immune reconstitution in haploidentical transplants. Results of unmanipulated stem-cell transplantation with using ATG and combined immunosuppression in mismatched/haploidentical transplant setting are promising. This paper focuses on recent advances in haploidentical hematopoietic stem-cell transplantation for hematologic malignancies

Hematopoietic Stem Cell Transplantation in Thalassemia and Sickle Cell Disease. Unicenter Experience in a Multi-Ethnic Population.

Hematopoietic stem cell transplantation (HSCT) still remains the only definitive cure currently available for patients with thalassemia and sickle cell anemia. Results of transplant in thalassemia and in sickle cell anemia have steadily improved over the last two decades due to improvements in preventive strategies, and effective control of transplant-related complications. From 2004 through 2009, 145 consecutive patients with thalassemia and sickle cell anemia, ethnically heterogeneous from Mediterranean and Middle East countries, were given HSCT in the International Center for Transplantation in Thalassemia and Sickle Cella Anemia in Rome. This experience is characterized by two peculiarities: patients were ethnically very heterogeneous and the vast majority of these patients were not regularly transfesed/chelated and therefore were highly sensitized due to RBC transfusions without leukodepletion filters. Consequently, they could have a high risk of graft rejection as a result of sensitization to HLA antigens. The Rome experience of SCT in patients with thalassemia and sickle cell anemia confirmed the results obtained in Pesaro, and most importantly showed the reproducibility of these results in other centers

Hematopoietic Stem Cell Transplantation in Thalassemia and Sickle Cell Anemia

The globally widespread single-gene disorders β-thalassemia and sickle cell anemia (SCA) can only be cured by allogeneic hematopoietic stem cell transplantation (HSCT). HSCT treatment of thalassemia has substantially improved over the last two decades, with advancements in preventive strategies, control of transplant-related complications, and preparative regimens. A risk class–based transplantation approach results in disease-free survival probabilities of 90%, 84%, and 78% for class 1, 2, and 3 thalassemia patients, respectively. Because of disease advancement, adult thalassemia patients have a higher risk for transplant-related toxicity and a 65% cure rate. Patients without matched donors could benefit from haploidentical mother-to-child transplantation. There is a high cure rate for children with SCA who receive HSCT following myeloablative conditioning protocols. Novel non-myeloablative transplantation protocols could make HSCT available to adult SCA patients who were previously excluded from allogeneic stem cell transplantation