双份HLA不全相合非血缘脐血移植成功治疗成人急性髓细胞白血病1例报告并文献复习

目的：探讨双份HLA不全相合非血缘脐血移植(UCBT)治疗成人急性髓细胞白血病的造血、免疫重建及植人状态。方法：l例急性单核细胞白血病，43岁，体重75kg，采用双份HLA不全相合非血缘脐血移植治疗急性髓细胞白血病患者1例。预处理方案由白消胺(BU)、环磷酰胺(CY)和抗胸腺细胞球蛋白(ATG)组成。应用环孢素A(CsA)和骁悉(MMF)预防移植物抗宿主病(GVHD)。结果：移植后19天造血重建，NK细胞和B细胞分别于术后30天和120天恢复正常，DNA短串联重复序列多态型(STR)和HLA差异分析显示移植后17天、30天、150天基因型表现为完全性双份供者的嵌合型，未发生GVHD。随访150天，血常规、骨髓象检查正常。结论：双份HLA配型不合的脐血用于成人脐血移植是可行的。     

HLA不全相合无血缘关系脐血移植治疗急性白血病

目的 :探讨HLA不全相合无血缘供者脐血移植 (UCBT)治疗血液系统恶性肿瘤造血重建、移植相关并发症的发生和生存情况。方法 :对 1例 15岁女性急性非淋巴细胞白血病 (ANLL)患者进行HLA 1个位点不相合2份UCBT。预处理方案 :采用白消安、环磷酰胺 (BU/CTX)方案 ,同时应用抗胸腺细胞球蛋白 (ATG)和Daclizumab(赛尼哌 ,zenapax)。移植物抗宿主病 (GVHD)的预防采用环孢菌素A(CsA)联合短程甲氨蝶呤 (MTX)和霉酚酸酯(MMF)方案。移植有核细胞数 (NC)为 4 .9× 10 7/kg ,CD34+ 细胞为 5 .36× 10 5/kg。结果 :中性粒细胞绝对计数 >0 .5× 10 9/L的时间为移植后第 15天 ;血小板计数 >5 0× 10 9/L的时间为移植后第 37天 ;全血细胞恢复正常的时间为移植后第 4 2天。移植后第 2 1天DNA指纹图提示供者型。受者已无病生存 2 0 0d。结论 :HLA 1个位点不相合的UCBT是可行的 ,对于体重量大的受者 2份脐血移植 (CBT)是可行的。     

非亲缘HLA不相合脐血移植治疗再生障碍性贫血

目的 :观察HLA位点不相合的非亲缘脐血细胞移植治疗重型再生障碍性贫血 (SAA)的疗效。方法 :采用 5～ 6个HLA位点相合的非亲缘脐血移植治疗SAA患者 1例。输入脐血单个核细胞数为 4.72× 10 7/kg。预处理方案为环磷酰胺 (5 0mg/kg·d-1× 4)、抗淋巴细胞球蛋白 (2 0mg/kg·d-1× 4)和全身照射 (3Gy)。用环胞素、骁悉和泼尼松预防移植物抗宿主病 (GVHD)。结果 :移植后白细胞下降至零 ,持续 12d ,中性粒细胞分别于移植后第 2 4天和第 2 6天恢复至 0 .5× 10 9/L和 1.0× 10 9/L ,血小板分别于移植后第 2 8天和第 82天达到 2 0× 10 9/L和 5 0× 10 9/L ,DNA短串重复序列PCR检测证实为持续稳定的供者造血。随访 12个月未发生急慢性GVHD。结论 :非亲缘脐血移植是治疗重型再障的一种有效的方法。     

异基因造血干细胞移植治疗白血病20例临床观察

目的探讨不同类型异基因造血干细胞移植(allo-HSCT)治疗白血病的疗效、造血重建及存活情况。方法哈尔滨血液病肿瘤研究所2003年3月至2006年7月进行异基因造血干细胞移植的白血病患者20例,其中同胞间人类白细胞抗原(HLA)相合的异基因外周血造血干细胞移植(allo-PBSCT)12例,无亲缘关系HLA不全相合脐血移植(UCBT)4例,无关供者的异基因外周血干细胞移植(其中1例HLA-CW位点亚型不合)3例,无关供者骨髓移植1例(经过去除红细胞处理)。结果19/20受者获造血重建,UCBT患者造血重建速度较HLA相合的同胞allo-PBSCT慢,异基因造血干细胞移植后20例患者中发生急性移植物抗宿主病(aGVHD)7例,其中4例Ⅰ~Ⅱ度,3例Ⅲ~Ⅳ度。3例患者死于复发,3例死于移植物抗宿主病(GVHD),另15例至今仍无病存活,中位存活时间30(1~41)个月。结论allo-HSCT是目前治愈白血病的有效方法,对于无同胞HLA相合的供者,选择较高细胞数量,HLA1~2个位点不合的UCBT仍然有效、可行。     

HLA配型相合的造血干细胞移植治疗重型再生障碍性贫血的临床研究

目的 评价HLA配型相合的异基因造血干细胞移植(allo-HSCT)治疗重型再生障碍性贫血(SAA)的疗效.方法 2000年1月至2008年11月采用allo-HSCT治疗SAA患者20例,其中同胞相合移植17例,非血缘关系移植3例.预处理采用环磷酰胺(Cy)50 mg·kg~(-1)·d~(-1)4 d加抗淋巴细胞免疫球蛋白(ATG)2.5 mg·kg~(-1)·d~(-1)或20 mg·kg~(-1)·d~(-1) d.移植物抗宿主病(GVHD)的预防方案为经典的环孢素A(CsA)联合短程甲氨蝶呤(MTX)及霉酚酸酯(MMF).同胞供者采集经重组人粒细胞集落刺激因子(G-CSF)动员的骨髓及外周血干细胞,非血缘供者单纯采集外周血干细胞.结果 回输单个核细胞中位数为7.89(4.00-14.21)×10~(8)/kg,所有患者均获供者造血重建,粒细胞植活中位时间14(11～20)d;血小板植活中位时间12(8～108)d.但1例患者发生晚期排斥,行另一供者二次移植后植活.21例次移植后共发生6例次急性GVHD(I度3例,Ⅱ度皮肤3例),发生率16%.19例生存期>100 d的患者中有7例发生慢性GVHD,其中4例为局限型,3例为广泛型.截至2009年2月28 日,经过中位18(2.0～106.8)个月的随访,共有17例患者无病生存,总生存率为82.5%.结论 采用Cy+ATG的预处理方案对SAA患者进行HLA配型相合HSCT,植活率高,可以获得良好的疗效.     

重型再生障碍性贫血85例治疗临床观察与分析

目的:观察采用异基因造血干细胞移植(Allo-HSCT)以及免疫抑制剂联合脐血输注治疗重型再生障碍性贫血(SAA)的疗效。方法:85例AA患者,有亲属全相合供者首选移植,无亲属全相合供者根据患者具体情况选择强烈免疫抑制剂联合脐血输注治疗或选择非血缘或不全相合移植方案治疗。其中42例SAA患者进行Allo-HSCT,43例SAA或极重型AA患者采用抗胸腺细胞球蛋白2.5~3.0 mg/(kg·d)×5d+环磷酰胺50mg/(kg·d)×2d联合非亲缘脐血输注支持治疗。结果:42例Allo-HSCT患者中,33例明显治愈,1例明显进步,1例无效,7例死亡,有效率为81.0%。43例强烈免疫抑制剂联合脐血输注的患者中,31例基本治愈,2例明显进步,3例无效,7例死亡,有效率为76.7%。总有效率为78.8%。结论:Allo-HSCT及免疫抑制剂联合脐血输注是治疗SAA的有效方法,均可取得满意的疗效。     

脐血移植治疗WAS的疗效观察

目的:分析湿疹血小板减少伴免疫缺陷综合征(WAS)患儿脐血移植后的疗效和影响因素,为供体选择和受体移植的时机提供经验。方法:5例WAS患儿接受非血缘脐血干细胞移植,分析移植前营养状态、移植时年龄、HLA相合度、移植后移植物抗宿主病(GVHD)及感染因素对移植效果的影响,随访时间截止到2016年1月。结果:5例WAS患儿成功植入。粒细胞植入时间分别为15d、12d、11d、14d、15d,血小板植入时间分别为39d、16d、16d、34d、36d,HLA高分辨检测显示供受体相合度分别为8/10、10/10、5/10、10/10、10/10;其中3例患儿移植前有巨细胞病毒血症,移植后血小板植入缓慢,1例中度营养不良的患儿移植后有皮肤及肠道重度GVHD和反复重症感染。结论:移植前患儿巨细胞病毒血症和移植前营养状态是影响血小板植入和预后的主要因素,HLA高分辨位点相合程度对粒细胞和血小板植入及GVHD没有显著影响。     

非血缘脐血移植失败行二次单倍型造血干细胞移植成功治疗骨髓增生异常综合征1例并文献复习

目的：探讨非血缘脐血移植治疗骨髓增生异常综合征失败后立即行半相合型造血干细胞二次移植作为解救方法的可能性和安全性。方法：1例骨髓增生异常综合征难治性血细胞减少伴多系增生异常（MDS-RCMD）3年余患者,进行非血缘HLA不全相合双份脐血造血干细胞移植,移植后＋30dSTRPCR检测移植物未植入,立即予患者进行半相合造血干细胞干细胞移植以挽救患者生命。供者为患者母亲,采用“骨髓加外周血联合造血干细胞移植”,预处理方案采用“抗胸腺细胞球蛋白＋福达拉滨”。结果：二次移植物成功植入,形成完全供者来源的造血与免疫功能,二次移植后12dANC〉0．5×10^5／L,＋15dPLT〉20×10^9／L,无急慢性GVHD等并发症的发生,随访19月余,患者获得长期无病生存。结论：非血缘脐血移植失败后,50d内行半相合型造血干细胞移植治疗骨髓增生异常综合征是安全、有效的挽救治疗措施。     

异基因造血干细胞移植治疗重型再生障碍性贫血Ⅱ型22例的疗效分析

目的:评估异基因造血干细胞移植(allo-HSCT)治疗重型再生障碍性贫血(SAA)Ⅱ型的疗效和安全性。方法:回顾性分析接受allo-HSCT治疗的22例SAAⅡ患者的临床资料,其中同胞相合供者移植10例,无关供者移植12例;18例行外周血造血干细胞移植,4例行骨髓联合外周血造血干细胞移植。预处理方案为环磷酰胺+抗人胸腺细胞球蛋白±氟达拉滨±白消安±低剂量TBI;采用环孢霉素A或他克莫司、短疗程甲氨蝶呤±霉酚酸酯预防移植物抗宿主病(GVHD)。回输单个核细胞中位数13.55(5.12~25.90)×10~8/kg,CD34~+细胞中位数7.30(2.19~40.32)×10~6/kg。结果:20例(90.91%)患者获得造血重建,可评估患者的中性粒细胞和血小板的中位植入时间分别为12(9~22)d和13(9~28)d。移植后2年急性GVHD、慢性GVHD和移植排斥、移植相关死亡累积发生率分别为40.00%、30.00%、9.09%和22.73%。细菌血流感染率22.73%,肺部侵袭性真菌病发生率40.91%,巨细胞病毒和EBV感染率分别为75.00%和50.00%;心、肝、肾功能不全发生率分别为45.45%、13.64%和36.36%。中位随访23(10~68)个月,17例患者生存,预期2年总生存率77.27%,预期2年无病生存率72.73%。单因素分析结果显示,移植后发生严重(Ⅱ~Ⅳ度)急性GVHD和重要脏器功能不全可显著降低allo-HSCT治疗SAAⅡ的疗效(P=0.018、0.009)。结论:同胞相合供者和无关HLA匹配供者alloHSCT是治疗SAAⅡ的有效手段。     

异基因造血干细胞移植治疗重型再生障碍性贫血Ⅱ型22例的疗效分析

目的:评估异基因造血干细胞移植(allo-HSCT)治疗重型再生障碍性贫血(SAA)Ⅱ型的疗效和安全性。方法:回顾性分析接受allo-HSCT治疗的22例SAAⅡ患者的临床资料,其中同胞相合供者移植10例,无关供者移植12例;18例行外周血造血干细胞移植,4例行骨髓联合外周血造血干细胞移植。预处理方案为环磷酰胺+抗人胸腺细胞球蛋白±氟达拉滨±白消安±低剂量TBI;采用环孢霉素A或他克莫司、短疗程甲氨蝶呤±霉酚酸酯预防移植物抗宿主病(GVHD)。回输单个核细胞中位数13.55(5.12~25.90)×10~8/kg,CD34~+细胞中位数7.30(2.19~40.32)×10~6/kg。结果:20例(90.91%)患者获得造血重建,可评估患者的中性粒细胞和血小板的中位植入时间分别为12(9~22)d和13(9~28)d。移植后2年急性GVHD、慢性GVHD和移植排斥、移植相关死亡累积发生率分别为40.00%、30.00%、9.09%和22.73%。细菌血流感染率22.73%,肺部侵袭性真菌病发生率40.91%,巨细胞病毒和EBV感染率分别为75.00%和50.00%;心、肝、肾功能不全发生率分别为45.45%、13.64%和36.36%。中位随访23(10~68)个月,17例患者生存,预期2年总生存率77.27%,预期2年无病生存率72.73%。单因素分析结果显示,移植后发生严重(Ⅱ~Ⅳ度)急性GVHD和重要脏器功能不全可显著降低allo-HSCT治疗SAAⅡ的疗效(P=0.018、0.009)。结论:同胞相合供者和无关HLA匹配供者alloHSCT是治疗SAAⅡ的有效手段。     

Unrelated cord blood transplantation in children with idiopathic severe aplastic anemia

Early results of unrelated cord blood transplantation (UCBT) for severe aplastic anemia (SAA) were poor with a high rate of engraftment failure. This was attributed to the combination of lower graft cell dose and intact host immune system. We performed UCBT in nine children (median age 9 years) with refractory SAA using increasingly immunosuppressive preparative regimens. The time from diagnosis to UCBT was 3.4-20 months (median age 7.2 years), with all children having failed at least one course of immunosuppression. Donor/recipient HLA matching was six of six (n=1), five of six (n=2) and four of six (n=6). The median nucleated cell dose infused was 5.7 x 10(7) cells/kg (range 3.5-20 x 10(7) cells/kg). Six patients were engrafted after the first UCBT. Two of the three patients without hematopoietic reconstitution were engrafted after a second UCBT. All children receiving >or=120 mg/kg of CY in the preparative regimen were engrafted. The median time to myeloid engraftment was 25 (17-59 days) days. Acute GVHD developed in two, and chronic GVHD in five patients. Five patients developed EBV viremia post transplant (lymphoproliferative disorder in three patients). At a median follow-up of 34 months, seven patients are alive and transfusion-independent. UCBT is a feasible treatment strategy for children with refractory SAA lacking a well-matched adult donor.     

Unrelated donor marrow transplantation in children with severe aplastic anaemia using cyclophosphamide, anti-thymocyte globulin and total body irradiation

We report a favourable outcome in 15 patients with severe aplastic anaemia (SAA) who were < 20 years of age and who underwent bone marrow transplantation (BMT) from a human leucocyte antigen (HLA)-matched unrelated donor. All patients were non-responders to intensive immunosuppressive therapy (IST) and were multiply transfused. The conditioning regimen consisted of cyclophosphamide (60 mg/kg/d, on d -4 and -3), anti-thymocyte globulin (2.5 mg/kg/d, on d -5 to -2) and total body irradiation (2.5 Gy x 2/d, on d -2 and -1). Patients received cyclosporine and methotrexate for prophylaxis of graft-versus-host disease (GVHD), except for the last four who received tacrolimus instead of cyclosporine. Donor/recipient pairs were identical for HLA class I and II antigens by serological typing, but four pairs were found to have a mismatch at the HLA-A, -B or -DRB1 locus by high-resolution typing. All patients achieved rapid engraftment and are alive at 2-86 months after transplantation (median follow-up, 51 months). Moderate to severe acute GVHD occurred in 5 out of 15 patients (33%); only one patient developed extensive chronic GVHD. Considering our encouraging results, unrelated donor transplantation for SAA is recommended as a salvage therapy in non-responders to IST.     

feasibility and Results of Bone Marrow Transplantation from an HLA-Mismatched Unrelated Donor for Children and Young Adults with Acquired Severe Aplastic Anemia

Treating patients with severe aplastic anemia (SAA) who fail to respond to immunosuppressive therapy (IST) and do not have an HLA-matched donor is challenging. We report favorable outcomes in 11 patients who underwent bone marrow transplantation (BMT) from an HLA-mismatched unrelated donor. The median age was 11 years (range, 3-20 years). The conditioning regimen consisted of cyclophosphamide (200 mg/kg), antithymocyte globulin (10 mg/kg), and total body irradiation (5 Gy). Patients received tacrolimus and methotrexate for prophylaxis against graft-versus-host disease (GVHD). Donorrecipient pairs were mismatched for the HLA-DR antigen in 8 patients by serologic typing. HLA-A and HLA-B antigens were mismatched in 1 and 2 patients, respectively. Ten patients achieved engraftment. One patient who failed to engraft was rescued by a second transplantation from her mother, who was mismatched at 2 HLA antigens. Acute GVHD of grades II to IV occurred in 2 patients. Three patients developed limited chronic GVHD, and 1 patient developed extensive chronic GVHD of the lung. All patients are alive at 9 to 56 months after transplantation (median, 33 months). Considering our encouraging results, HLA-mismatched unrelated-donor BMT for SAA is feasible as a salvage therapy for nonresponders to IST.     

配型不合造血干细胞移植治疗重型再生障碍性贫血的疗效及安全性

目的 研究人类白细胞抗原(HLA)配型不合造血干细胞移植治疗重型再生障碍性贫血(SAA)的疗效和安全性.方法 从2006年1月至2010年5月共入选17例SAA患者接受配型不合造血干细胞移植治疗,供受者间HLA 2个位点不合8例,3个位点不合9例,以改良马利兰/环磷酰胺+抗人胸腺细胞免疫球蛋白(BU/CY+ATG)为预处理方案,进行骨髓加外周血干细胞移植.结果 所有病例均达到完全供者植入.发生Ⅲ～Ⅳ度急性移植物抗宿主病(GVHD)3例,14例可评估病例中,广泛型慢性GVHD 1例;中位随访285(60～1670)d,11例患者生存,9例血象恢复正常,另2例脱离输血.6例患者死于移植相关合并症.结论 当无HLA配型相合同胞供者时,SAA患者采用HLA配型不合移植是可行的治疗选择.

Abstract：

Objective To study the efficacy and safety of human leukocyte antigen (HLA)mismatched hematopoietic stem cell transplantation (HSCT) on severe aplastic anemia(SAA). Methods From January 2006 to May 2010, 17 patients received mismatched HSCT. HLA antigens were 3-locimismatched in 9 patients, 2-loci-mismatched in 8. All patients received recombinant human granulocyte colony-stimulating factor (rhG-CSF) primed bone marrow cells plus peripheral blood stem cells after modified busulfan/cyclophosphamide + antithymocyte immunoglobulin (BU/CY + ATG ) conditioning regimen. Results All patients achieved full donor type engraftment. Grade Ⅲ-Ⅳ graft versus host disease (GVHD) occurred in 3 patients and extensive chronic GVHD in 1. With a median following-up time of 285(60-1670) d, 11 patients were alive, 9 of them had normal blood counts and the other 2 were blood transfusion independent. Six patients died of transplant-related complications. Conclusion Mismatched HSCT is a feasible and safe option for SAA patients without sibling identical donors.     

Graft rejection and hyperacute graft-versus-host disease in stem cell transplantation from non-inherited maternal-antigen-complementary HLA-mismatched siblings

Human leukocyte antigen (HLA)-mismatched stem cell transplantation from non-inherited maternal antigen (NIMA)-complementary donors is known to produce stable engraftment without inducing severe graft-versus-host disease (GVHD). We treated two patients with acute myeloid leukemia (AML) and one patient with severe aplastic anemia (SAA) with HLA-mismatched stem cell transplantation (SCT) from NIMA-complementary donors (NIMA-mismatched SCT). The presence of donor and recipient-derived blood cells in the peripheral blood of recipient (donor microchimerism) and donor was documented respectively by amplifying NIMA-derived DNA in two of the three patients. Graft rejection occurred in the SAA patient who was conditioned with a fludarabine-based regimen. Grade III and grade IV acute GVHD developed in patients with AML on day 8 and day 11 respectively, and became a direct cause of death in one patient. The findings suggest that intensive conditioning and immunosuppression after stem cell transplantation are needed in NIMA-mismatched SCT even if donor and recipient microchimerisms is detectable in the donor and recipient before SCT.     

Hematopoietic stem cell transplantation for severe aplastic anemia—experience of an institute in Taiwan

Hematopoietic stem cell transplantation (HSCT) is an accepted treatment strategy for patients with severe aplastic anemia (SAA). We report our experience in a general hospital in Taiwan. From March 1985 to July 2001, 79 consecutive SAA patients, 46 male and 33 female, with a median age of 22 (4–43) years, received 80 courses of transplantation. Cyclophosphamide and total body radiation were used for the conditioning regimen, and cyclosporine-A and methotrexate for graft-versus-host disease (GVHD) prevention. Patients were followed for a median of 39 months (from 8 days to 194 months). Myeloid and platelet engraftment occurred in a median of 15 (8–27) days and 18 (8–77) days, respectively. Three patients had primary and three patients secondary graft failure. Five patients (6.8%) had grade II–IV acute GVHD in 73 evaluable patients. Chronic GVHD occurred in 23 (34.8%) patients, with extensive stage in six. Only two patients had CMV disease. The projected 3- and 5-year overall survival rates estimated by the Kaplan-Meier method were 76.08 and 74.13%, respectively. Age at transplant, non-sibling donor, mononuclear cell dose, grade II–IV acute GVHD, interval from diagnosis to transplant, and red blood cell and platelet transfusion before transplant were poor prognostic factors for overall survival by univariate analysis. Grade II–IV acute GVHD was the only prognostic factor affecting overall survival after multivariate Cox regression analysis (P=0.040). In conclusion, SAA patients receiving HSCT have good long-term survival. The low incidence of acute GVHD in our patients may be related to ethnicity.     

Bone marrow transplantation for severe aplastic anaemia using cyclosporin: long-term follow-up

Between 1980 and 1986 we transplanted 49 patients from genotypically identical sibling donors for severe aplastic anaemia (SAA). Patients were predominantly adults, median age 22 years (3-47). Forty-six were multiply transfused prior to referral. The median pre-transplant disease duration was 4 months (1-72). Pre-transplant conditioning was with cyclophosphamide (CY) 200 mg/kg. Cyclosporin A (CSA) was given from 1 day before the transplant and continued for 9-12 months. Eight of 48 evaluable patients did not achieve initial engraftment (early graft failure). Six of these episodes occurred in the eight cases transplanted more than 1 year after diagnosis, four of whom died. Thirteen of 44 (30%) evaluable patients (with stable engraftment after one or two transplants) had grade III-IV acute graft-versus-host disease (GVHD). Only three of 35 patients surviving more than 100 days with sustained engraftment developed generalized chronic GVHD; two died. An additional 10 patients developed localized chronic GVHD, which was very mild, transient and related to CSA withdrawal. Four long-term survivors are known to have autologous marrow function. All survivors have Karnofsky scores of greater than 90%. We conclude that the use of CSA after bone marrow transplantation for SAA is associated with good long-term survival and minimal on-going chronic GVHD. Early graft failure was frequent when transplantation was delayed beyond 1 year from diagnosis.     

Acute graft-versus-host disease after unrelated donor umbilical cord blood transplantation: analysis of risk factors

Acute graft-versus-host disease (GVHD) occurs less frequently after umbilical cord blood transplantation (UCBT). More recent investigations include the use of 2 partially human leukocyte antigen (HLA)-matched UCB units, or double UCB graft, to meet the minimum cell-dose requirement. The purpose of this analysis was to assess the relative risk of acute GVHD in 265 consecutive patients receiving transplants with UCB graft composed of 1 (n = 80) or 2 (n = 185) units. The incidence of grade III-IV acute GVHD was similar between cohorts. However, the incidence of grade II-IV acute GVHD was higher among double UCBT recipients (58 vs 39%, P < .01). Three risk factors for grade II-IV acute GVHD were identified in multiple regression analysis: use of 2 UCB units, use of nonmyeloablative conditioning, and absence of antithymocyte globulin in the conditioning regimen. Transplantation-related mortality (TRM) at 1 year, however, was significantly lower after double UCBT (24 vs 39%, P = .02) even if recipients had grade II-IV acute GVHD (20 vs 39%, P = .05). These data suggest that, despite a higher incidence of grade II acute GVHD in recipients of 2 partially HLA-matched UCB units, there is no adverse effect on TRM. This study is registered at (http://www.clinicaltrials.gov) under the identifiers NCT00305682 and NCT00309842.     

Hematopoietic stem cell transplantation for high-risk adult patients with severe aplastic anemia; reduction of graft failure by enhancing stem cell dose

BACKGROUND AND OBJECTIVES: The main causes of failure after allogeneic hematopoietic stem cell transplantation (HSCT) in patients with severe aplastic anemia (SAA) are graft-versus-host disease (GVHD), infection and graft failure, often exacerbated by large numbers of transfusions and prolonged disease duration before transplant. This study retrospectively analyzes the outcome and factors related to survival or graft failure in high-risk patients with SAA receiving HSCT in our institution. DESIGN AND METHODS: Between January 1995 and December 1999, 40 consecutive adult patients who were multi-transfused (more than 40 units of red blood cells +/- platelets) and/or had a 3 years or longer period prior to transplant were enrolled. Their median age was 27.5 years (range, 16 to 43) and 21 (52.5%) were women. All donors were human leukocyte antigen (HLA)-matched siblings. Before transplant, 29 patients (72.5%) received a course of antithymocyte globulin (ATG) and cyclosporin A (CsA). The median interval from diagnosis to transplant was 59 months (range, 2 to 216). The median number of transfusions was 115 units (range, 10 to 480). All patients received a conditioning regimen of cyclophosphamide, ATG, and procarbazine. Our patients received either bone marrow (BM) alone (n=20) or BM+peripheral blood stem cells (PBSC) (n=20) as a stem cell source. T-cells of PBSC were depleted using the CD34 enrichment method. GVHD prophylaxis consisted of CsA and short-term methotrexate. RESULTS: In the BM+PBSC group, neutrophil recovery to 0.5 x 10(9)/L and platelet recovery to 20 x 10(9)/L were achieved more rapidly than in the BM group (p=0.005 and 0.039, respectively). The incidences of graft failure, grade II to IV acute GVHD, and chronic GVHD were 22.5%, 12.8% and 23.1%, respectively. Graft failure occurred in 2 of 20 patients (10%) receiving BM+PBSC and in 7 of 20 (35%) receiving BM alone (p=0.069). Seven of 9 patients who had graft failure received a booster treatment and recovered normal marrow function. GVHD incidence was comparable between the BM+PBSC and BM groups. Six patients (15%) died from graft failure (n=2), interstitial pneumonia (n=2), cyclophosphamide-induced heart failure (n=1), and chronic GVHD followed by pneumonia (n=1). The Kaplan-Meier estimate of survival was 83.7% with a median follow-up duration of 40.5 months (range 8-67). In multivariate analysis only chronic GVHD adversely influenced survival (p=0.042). INTERPRETATION AND CONCLUSIONS: These results suggest that HSCT is an effective treatment for multi-transfused SAA patients with prolonged disease duration. It is highly possible that the infusion of a large number of stem cells leads to a reduction of graft failure and a faster speed of engraftment. Booster treatment is successful in achieving engraftment in patients with graft failure.     

Tacrolimus for prevention of graft-versus-host disease after mismatched unrelated donor cord blood transplantation.

Ten children with hematologic malignancies or a storage disease underwent transplantation using cord blood cells from an unrelated donor mismatched for 1 (n = 7) or 2 (n = 3) HLA antigens. The median total nucleated cell dose was 4.0 (range, 2.2-7.1) x 10(7)/kg. GVHD prophylaxis consisted of tacrolimus dose-adjusted to maintain a whole blood level of 5-15 ng/ml with or without methotrexate 5 mg/m2 i.v. on days 1, 3, 6 and 11. Corticosteroids were not administered prophylactically. Median follow-up is 12 months (range, 5-28 months). One patient had autologous recovery and subsequently relapsed 153 days post transplant. For the remainder of the patients, the median time to an ANC >0.5 x 10(9)/l was 21 days (range, 19-38 days), and the median time to platelets >20 x 10(9)/l was 39 days (range, 21-97 days). The actuarial risk of grade 2 GVHD was 77% (95% CI, 49-100%), and no patient had grades 3-4 GVHD. Two patients developed chronic GVHD. The survival rate is 90% (95% CI, 81-100%). The combination of tacrolimus and minidose methotrexate is active for the prevention of severe but not moderate acute GVHD after mismatched unrelated donor cord blood transplantation.