单倍体相合异基因造血干细胞移植治疗肾上腺脑白质营养不良

目的 X-连锁肾上腺脑白质营养不良(X-linked adrenoleukodystrophy,ALD)是一种严重的遗传性疾病,导致神经系统迅速恶化和过早死亡,异基因造血干细胞移植(hematopoietic stem cell transplantation,HSCT)仍然是唯一能阻止该疾病神经症状的治疗方法。然而,许多患者缺乏合适的人类白细胞抗原(human leukocyte antigen,HLA)匹配相关供体,必须依赖替代供体作为干细胞来源,故本研究探讨采用单倍体相合异基因造血干细胞移植治疗肾上腺脑白质营养不良患儿。方法 2014年12月至2018年12月, 8例无HLA完全相合供体的ALD儿童接受了单倍体异基因造血干细胞移植治疗。预处理方案主要用药为马利兰(9.6 mg/kg)、环磷酰胺(200 mg/kg)和氟达拉滨(90 mg/m ²),预防移植物抗宿主病的药物包括抗人胸腺细胞免疫球蛋白、环孢菌素A、霉酚酸酯和短疗程甲氨蝶呤。 结果 8例患儿均接受父亲来源的单倍体异基因造血干细胞移植治疗。患儿中位年龄为8岁(范围5~12岁),供者中位年龄为36(32~40)岁。干细胞来源采用粒细胞集落刺激因子(granulocyte colony-stimulating factor,G-CSF)动员的骨髓联合动员后的外周血采集物,总有核细胞中位数为10.89 (9.40~12.16)×10 ⁸/kg, CD34 ⁺细胞中位数为7.06(0.74~7.80)×10 ⁶/kg。中性粒细胞植入发生在移植后11 d(范围8~13 d),血小板植入中位时间为移植后10 d(范围8~12 d), 所有患儿在植入时均获得完全的供体细胞嵌合。4例患儿患有Ⅱ~Ⅳ级急性移植物抗宿主病,1例患儿患有慢性移植物抗宿主病,均无重度慢性移植物抗宿主病(graft-versus-host disease GVHD)发生。所有患儿中发生2例巨细胞病毒(cytomegalovirus,CMV)血症,2例EB病毒(Epstein-Barr virus,EBV)血症。总体来看,7例患儿无严重相关移植合并症发生且均生存,1例患儿移植后125 d癫痫后脑疝死亡。 结论 初步观察表明,采用这种新方案的单倍体异基因干细胞移植能成功地实现ALD患者的完全供体嵌合;根据我们的经验,单倍体相合异基因造血干细胞移植治疗肾上腺脑白质营养不良是安全可行的。

Haploidentical allogenetic hematopoietic stem cell transplantation for X-linked adrenoleukodystrophy

Objective: X-linked adrenoleukodystrophy (ALD) is a severe inherited disorder leading to rapid neurological deterioration and premature death. Allogeneic hematopoietic stem cell transplantation (HSCT) is still the only treatment that halts the neurologic symptoms in ALD. However, many patients lack suitable human leukocyte antigen (HLA) matched related donors and must rely on alternative donors for a source of stem cells. The purpose of this study was to explore the outcomes of haploidentical allogeneic stem cell transplantation for ALD patients.Methods: Between December 2014 and December 2018, eight children with ALD lacking HLA matched related or unrelated donors were treated with haploidentical allogeneic hematopoietic stem cell transplantation. The patients received conditioning regimen with busulfan 9.6 mg/kg, cyclophosphamide 200 mg/kg and fludarabine 90 mg/m ². Graft-versus-host disease (GVHD) prophylaxis consisted of anti-human thymocyte globulin, cyclosporine A, mycophenolate mofetil and short course of methotrexate. Results: All the 8 children received allogeneic stem cell transplants from their fathers. The median age of the recipients was 8 (range: 5-12) years. The median age of the donors was 36 (range: 32-40) years. All the recipients received granulocyte colony-stimulating factor (G-CSF) mobilized bone marrow and peripheral blood-derived stem cells. The median number of total mononuclear cells dose and CD34 ⁺ dose was 10.89 (range: 9.40-12.16)×10 ⁸/kg and 7.06 (range: 0.74-7.80)×10 ⁶/kg, respectively. Neutrophil engraftment occurred a median of 11 days (range:8-13 days) after transplantation. Platelet engraftment occurred a median of 10 days (range:8-12 days) after transplantation. All the patients achieved complete donor chimerism at the time of engraftment. Four patients had grades Ⅱ-Ⅳ acute GVHD and 1 had chronic graft-versus-host disease. No severe chronic GVHD occurred. Among all the children, 2 had cytomegalovirus (CMV) DNAemia and 2 Epstein-Barr virus (EBV) DNAemia. Overall, seven of them survived and had no major complications related to transplantation. One died of cerebral hernia after epilepsy 125 days after transplantation. Conclusion: The preliminary observation demonstrates that haploidentical allogeneic stem cell transplantation with this novel regimen could successfully achieve full donor chimerism in ALD patients. According to our experience, haploidentical allogeneic hematopoietic stem cell transplantation is safe and feasible in the treatment of X-linked adrenoleukodystrophy.