HLA haploidentical peripheral blood stem cells transplantation for β thalassemia major / 中华血液学杂志

<p><b>OBJECTIVE</b>To evaluate the feasibility of HLA haploidentical peripheral blood hematopoietic stem cell transplantation (PBSCT) for patients with β thalassemia major.</p><p><b>METHODS</b>Sixteen patients with β thalassemia major received HLA haploidentical PBSCT from parents. Two conditioning regimens were used. Regimen A was adopted before December 2007, which consisted of fludarabine (total 150 mg/m²), busulfex (total 520 mg/m²), cyclophosphamide (CTX, total 100 mg/kg), antithymocyte globulin (ATG, total 10 mg/kg) and total body irradiation of 3 Gy. Regimen B was adopted after December 2007, which consisted of fludarabine (total 240 mg/m²), busulfex (total 520 mg/m²), CTX (total 100 mg/kg), and ATG (total 10 mg/kg). Combination of cyclosporin (CsA), methotrexate (MTX) and mycophenolate mofetil (MMF) were used for prophylaxis of graft-versus-host disease (GVHD).</p><p><b>RESULTS</b>Of 16 patients, 14 (87.5%) had sustained engraftment. The median days of neutrophil exceeding 0.5 × 10⁹/L and platelet exceeding 20 × 10⁹/L were 13 days (range 10 - 17 days) and 15 days (range 14 - 20 days) after PBSCT, respectively. Complete chimerism was achieved in all the 14 patients at one month after PBSCT. One patient lost his graft with autologous reconstitution 52 days after transplantation. Four patients had grade II-IV acute GVHD and one patient had chronic extensive GVHD. In the 49-month median follow-up duration, 13 of 16 patients were alive in disease-free situation.</p><p><b>CONCLUSION</b>HLA haploidentical PBSCT, which could provide stable and sustained engraftment for thalassemia major patients with no HLA identical donor, is a promising treatment strategy.</p>

Are leukemic patient bone marrow mesenchymal stem cells malignant? / 中国实验血液学杂志

The study was aimed to explore whether there are leukemic characteristics in the bone marrow mesenchymal stem cells (BMMSC) from leukemic patients as compared with normal controls. The mesenchymal stem cells from bone marrow of normal volunteers and patients with APL and CML were isolated, then cultured and proliferated in vitro. The morphology, growth curve and cell surface markers of two different sources mesenchymal stem cells were investigated for detecting whether the bone marrow mesenchymal stem cells derived from leukemia patients have the specific abnormal fusion gene of leukemia cells through fluorescent in situ hybridization. The results indicated that there was no significant difference between the mesenchymal stem cells derived from different subjects, the bone marrow mesenchymal stem cells derived from leukemia patients did not have the clonal malignant fusion gene as seen in the leukemia cells. Taken altogether, mesenchymal stem cells derived from leukemia patients had no biological differences as compared with those from normal volunteers, and no malignant clonal abnormality was found. It is concluded that mesenchymal stem cells derived from leukemia patients as an alternative vehicle may be used for assistant of autologous hematopoietic stem cell transplantation or cell therapy and gene therapy.