Effects of preexisting donor-specific HLA antibodies for graft failure in un-manipulated haploidentical hematopoietic stem cell transplantation / 中华血液学杂志

Objective: To investigate the effects of donor-specific HLA antibodies(DSA) for graft failure in un-manipulated haploidentical hematopoietic stem cell transplantation(haplo-HSCT) and the feasible treatment for DSA. Methods: HLA antibodies were examined using the Luminex-based single Ag assay for 92 patients who were going on haplo-SCT and the correlations of graft failure and DSA among the patients who had finished SCT were analyzed. Results: Of the total 92 patients who were going on haplo-HSCT, sixteen (17.4%) patients were HLA Ab-positive, including six (6.5%) patients with antibodies corresponding to donor HLA Ags (DSA-positive). Among the patients who had finished the haplo-HSCT with conventional myeloablative conditioning regimen, the engraftment rate was significantly higher in DSA (-) patients than that in DSA (+) patients [92.3% (24/26) vs 25.0%(1/4), χ2=8.433, P=0.004] and DSA was the only factor relevant with graft failure in multiple-factor analysis [OR=12.0(95% CI 1.39-103.5), P=0.024]. Strategies to decrease antibody levels were taken for 4 patients, two were their first transplantations, and the other two patients were their second haplo-HSCT. Three of the four patients were HLA-I-DSA positive and had gained donor engraftment by means of donor platelet transfusions to decreased the level of DSA, the fourth patient with both HLA-I and HLA-II DSA also gained engraftment with the treatments of TBI, rituximab and donor platelet transfusion. Conclusion: DSA is one of the key factors of graft failure in haplo-HSCT. Donors should be selected on the basis of an evaluation of HLA antibodies before transplantation. If haplo-HSCT from donors with DSA must be performed, then recipients should be treated for DSA to improve the chances of successful engraftment.

Outcome of allogeneic hematopoietic stem cell transplantation from HLA-matched sibling donor for 41 cases of severe aplastic anemia / 中华血液学杂志

<p><b>OBJECTIVE</b>To evaluate the outcome of allogeneic hematopoietic stem cell transplantation (allo-HSCT) from HLA-matched sibling donor (MSD allo-HSCT) for severe aplastic anemia (SAA).</p><p><b>METHODS</b>The clinical data of 41 SAA patients received MSD allo-HSCT from May. 2003 to Aug. 2011 were analyzed retrospectively. 24 patients were male, 17 were female. Median age was 23 (5 - 43) years old. 28 patients had SAA-I, 9 had SAA-II, and 4 had post-hepatitis aplastic anemia. 17 patients received allogeneic bone marrow (BM) transplantation (allo-BMT), and 24 received allogeneic peripheral blood stem cell (PBSC) transplantation (allo-PBSCT). The conditioning regimens: 20 patients received cyclophosphamide (CY) + anti-thymocyte globulin (ATG) + fludarabine (Flu), 21 received CY + ATG + Flu+ cytarabine (Ara-C) ± busulfan (Bu)/melphalan (Mel). Prophylaxis for graft-versus-host disease (GVHD): 25 patients received cyclosporine (CSA) plus short-term methotrexate (MTX), 16 received tacrolimus (FK506) plus short-term MTX. The median number of infused CD34(+) cells were 3.48 (2.39 - 4.80)×10(6)/kg in allo-BMT and 2.95 (1.27 - 5.98)×10(6)/kg in allo-PBSCT, respectively.</p><p><b>RESULTS</b>Hematopoietic reconstitution was observed in all 41 patients (100%). The median time of neutrophils (ANC) reached to 0.5×10(9)/L and platelets (PLT) reached to 20×10(9)/L were 14 (10 - 23) days and 19 (8 - 38) days, respectively. 12 patients developed acute GVHD (aGVHD), out of which 11 developed grade I-II aGVHD, and one developed grade IV. 2 patients occurred chronic GVHD (cGVHD), out of which one with local cGVHD and the other with extensive. 4 patients occurred graft rejection (GR), all of them recovered haemopoiesis and survived after donor PBSC infusion. 5 patients (12.2%) died, out of which one died of extensive cGVHD, and 4 died of invasive fungal infections (IFI). Median follow-up time was 23 (3 - 79) months. 36 patients survived. 5-year estimated overall survival (OS), disease free survival (DFS), and transplant-related mortality (TRM) was (81.1 ± 9.0)%, (68.4 ± 11.0)%, and (18.9 ± 9.0)%, respectively. Univariate analysis showed that lover OS had significant correlation with receiving PBSCT, occurrence of aGVHD, the number of infused CD34(+) cells no more than 2.5×10(6)/kg, the number of red blood cell (RBC) transfusion before transplant more than 30 U and occurrence of IFI after transplantation (P = 0.034, 0.001, 0.006, 0.000, 0.001, respectively). Occurrence of aGVHD had significant correlation with the disparity between donor and recipient ABO blood groups, the number of PLT transfusion more than 100 U, and the number of RBC transfusion more than 30 U before transplantation, the number of infused CD34(+) cells no more than 2.5× 10(6)/kg (P = 0.019, 0.038, 0.005, 0.005, respectively). The occurrence of GR had significant correlation with the number of PLT transfusion more than 100 U before transplantation (P = 0.038).</p><p><b>CONCLUSION</b>MSD allo-HSCT is an effective therapy for patients with SAA. Lower number of blood transfusion before transplantation, use of BMT, more number of infused CD34(+) cells can effectively prevent and treat aGVHD and IFI after transplantation, which may improve the efficacy of MSD allo-HSCT for SAA.</p>