Xuedong Wu

A novel conditioning regimen improves outcomes in β-thalassemia major patients using unrelated donor peripheral blood stem cell transplantation

We used a novel NF-08-TM transplant protocol based on intravenous busulfan, cyclophosphamide, fludarabine, and thiotepa in 82 consecutive patients with β-thalassemia major (TM), including 52 with allogeneic peripheral blood stem cell transplantation (PBSCT) from unrelated donors (UDs) with well-matched human leukocyte antigens and 30 with hematopoietic stem cell transplantation (HSCT) from matched sibling donors (MSDs). The median age at transplantation was 6.0 years (range, 0.6-15.0 years), and the ratio of male-to-female patients was 56:26. The median follow-up time was 24 months (range, 12-39 months). The estimated 3-year overall survival and TM-free survival were 92.3% and 90.4% in the UD-PBSCT group and 90.0% and 83.3% in the MSD-HSCT group. The cumulative incidences of graft rejection and grades III-IV acute graft-versus-host disease were 1.9% and 9.6%, respectively, in the UD-PBSCT group and 6.9% and 3.6%, respectively, in the MSD-HSCT group. The cumulative incidence of transplant-related mortality was 7.7% in the UD-PBSCT group and 10.0% in the MSD-HSCT group. In conclusion, UD-PBSCTs using the well-tolerated NF-08-TM protocol show similar results to MSD-HSCTs and can be used to treat β-thalassemia patients in the absence of MSDs.

An Innovative Approach to Bone Marrow Collection and Transplantation in a Patient with β-Thalassemia Major: Marrow Collection Using a Perfusion Method Followed by Intra-Bone Marrow Injection of Collected Bone Marrow Cells

Using small animals (mice and rats) and monkeys, we have found that the combination of bone marrow collection using the perfusion method (PM) and intra-bone marrow-bone marrow transplantation (IBM-BMT) of the collected cells is safe and effective in treating various intractable diseases. Based on these findings, we attempted to apply this method to humans. We report here the first case of a patient (6 years old) with β-thalassemia major who underwent allogeneic BMT using this new PM + IBM-BMT method. The white blood cell counts of the patient gradually increased to more than 1500/µL by day 47 and continued to increase, reaching the highest level (8600/µL) on day +55. Fluorescence in situ hybridization data on day +33 showed that 98% of the peripheral blood cells were from the donor. Notably, there were no symptoms of graft-versus-host disease (GvHD). However, on day +56, the patient regrettably died of asphyxia resulting from sticky sputum. There was no evidence of infection (in the lung or liver) or GvHD (in the skin) by necropsy. We hope that this case report will help make our new strategies more readily available for the treatment of patients with various intractable diseases.

Apoptosis of CD19+ chimeric antigen receptor T cells after treatment with chemotherapeutic agents

The use of chemotherapeutic agents prior to treatment with infusion of cluster of differentiation (CD)19-chimeric antigen receptor (CAR)-T cells is important for the efficacy of clinical therapies against hematological malignancies. However, the effect of chemotherapeutic agents on CD19-CAR-T cells and the associated underlying mechanisms remain unknown. The first aim of the present study was to determine the effect of chemotherapeutic agents on CAR-T cells using the in vitro Cell Counting kit 8 assay. The second aim was to evaluate the abilities of fludarabine (FDR) and mafosfamide (MFA; a metabolite of cyclophosphamide) to induce apoptosis of CD19-CAR-T cells via the use of Annexin V/propidium iodide double staining. In addition, a JC-1 fluorescent probe was used to detect alterations in cell membrane potential, and flow cytometry analysis was used to measure concentrations of caspase-3/7 to identify apoptotic pathways of CD19-CAR-T cells. The data of the present study suggested that FDR and MFA inhibit the activities of CD19-CAR-T cells. Alterations to the mitochondrial membrane potential and an increase in the concentration of caspase-3/7 indicated early apoptosis of FDR- and MFA-treated CD19-CAR-T cells. The present study laid a theoretical foundation for the development of programs for clinical treatment.

Transplant Outcomes in Beta-Thalassemia Major Patients Receiving Combined Granulocyte Colony-Stimulating Factor-Primed Bone Marrow and Cord Blood Graft Compared to Granulocyte Colony-Stimulating Factor-Primed Bone Marrow Alone

Background: Hematopoietic stem cell transplantation (HSCT) is currently the only curative treatment for thalassemia majorTM. Graft rejection (GR) and graft-versus-host disease (GVHD) are the primary obstacles to a successful outcome. Methods: We conducted a retrospective study of HSCT in 29 children (median age at transplantation: 6 years) with Beta-thalassemia (β-TM) after the combined infusion of granulocyte colony-stimulating factor-primed bone marrow (G-BM) and cord blood (CB) from the human leukocyte antigen (HLA)-identical sibling donors. We also compared the outcomes of the co-transplanted children with those of children with β-TM who received G-BM alone from an HLA-identical sibling donor (n = 26). Results: Compared to the G-BM transplant (G-BMT) recipients, those who received a co-transplant had a lower incidence of grade ≥II acute (17.24 vs. 30.7%, p = 0.047) and limited chronic (0 vs.15.4%, p = 0.022) GVHD as well as a lower incidence of GR (0 vs. 7.7%, p = 0.132). Neutrophil recovery time was faster in the co-transplant group (18.5 vs. 21 days, p = 0.04). All the patients were monitored until December 31, 2016; the median follow-up time was 74 months, and the 5-year thalassemia-free survival rate was 89.7% in the co-transplant group and 84.6% in the G-BMT-alone group (p = 0.590). Conclusions: A combined CB and G-BM graft from an HLA-identical sibling donor is an effective treatment option for TM in children, with less acute and chronic GVHD.

Successful engraftment determined by the quality rather than quantity of the haematopoietic graft: a lesson from co-transplantation of unrelated cord blood and mobilized haploidentical peripheral blood in monozygotic twins.

Keywords: thalasssaemia; killer-cell immunoglobulin-like receptor; haematopoietic stem cell transplantation; human leucocyte antigen; engraftment