造血干细胞移植治疗重型β- 地中海贫血合并肢带型肌营养不良1 例报告并文献复习

目的探讨重型β-地中海贫血合并肢带型肌营养不良(LGMD)的造血干细胞移植治疗效果。方法回顾分析1例重型β-地中海贫血(CD17纯合子突变)合并LGMD2E患儿行亲缘性HLA全相合造血干细胞移植的治疗过程。结果患儿,女,3岁5个月,供者为妹妹。移植预处理方案:氟达拉滨、白消安、环磷酰胺及抗人胸腺细胞免疫球蛋白;预防移植物抗宿主病方案:环孢素、吗替麦考酚酯及短程甲氨蝶呤。经静脉输注供者骨髓血406 mL,单个核细胞数11.3×10~8/kg,术后监测患儿血常规、植入证据及激酶水平。造血干细胞移植后,患儿重建造血及免疫功能。植入证据提示完全供者嵌合,嵌合率100%,但血清酶学无明显下降,血清肌酸激酶维持在20 000～25 000 IU/L,四肢肌力逐渐下降,近期双下肢肌力3～4级,双上肢肌力4级,易摔倒。结论异基因造血干细胞移植可以治愈患儿的地中海贫血,但无法改善肌营养不良症状。     

造血干细胞移植治疗DOCK8基因突变致高IgE综合征2例病例报告

目的：评估异基因造血干细胞移植治疗DOCK8基因突变所致的高IgE综合征（HIES）患儿的治疗效果。方法：回顾性收集2例接受异基因造血干细胞移植治疗DOCK8基因突变所致的HIES患儿的临床特征、实验室检查、治疗和效果。结果：2例HIES患儿，例1男，移植时年龄7岁；例2女，移植时年龄9岁。例1采用同胞全相合外周血干细胞移植，例2采用非亲缘全相合脐血干细胞移植。均采用白消安联合氟达拉滨为基础的减低强度预处理方案，顺利植入并获得造血重建。中性粒细胞植入时间例1为移植后12 d，例2为移植后24 d；血小板植入时间例1为移植后13 d，例2为移植后35 d。移植后14 d嵌合检测提示为完全供者细胞嵌合。2例患儿移植期间肺部感染均有加重，经对症治疗好转。例1接受同胞供者移植，发生皮肤Ⅰ度急性移植物抗宿主反应，甲泼尼龙治疗后缓解。无其他移植相关并发症发生。2例移植后嗜酸性粒细胞及血清IgE水平均较移植前显著下降，例1和例2分别随访至移植后18和23个月，均无病生存。结论：DOCK8基因突变所致的HIES患儿可通过异基因造血干细胞移植治愈，宜采用减低强度预处理方案，同胞相合供者是最佳供者选择，非亲缘脐血干细胞移植也能取得良好疗效。     

外周血造血干细胞移植联合间充质干细胞输注治疗范可尼贫血患儿1例并文献复习

目的分析造血干细胞移植联合间充质干细胞输注对范可尼贫血(FA)患儿的治疗效果。方法通过分析1例.FA患儿外周血造血干细胞移植联合间充质干细胞输注治疗的临床资料,观察此种治疗方法对患儿的治疗效果及预后的影响。结果患儿于移植+13 d中性粒细胞植活,+15 d血小板植活,移植后供受者基因嵌合率为99.83%。移植后1.5个月血清CMV-DNA、EBV-DNA阳性,经免疫抑制剂减量及抗病毒治疗后转阴。移植后2个月出现皮肤GVHD(I度),未调整免疫抑制剂剂量,行间充质干细胞输注治疗4次后GVHD消失。移植后6个月,患儿出现血红蛋白水平下降,复查供受者基因嵌合率为57.8%,考虑出现移植物排斥,逐渐减停免疫抑制剂,供受者基因嵌合率复升至81.83%,血象恢复正常,无GVHD表现。现为移植后1.5年,患儿血象持续正常,供受者基因嵌合率维持在95%以上,FA相关基因检测持续转阴。结论造血干细胞移植是根治FA的重要治疗手段,健康供者骨髓间充质干细胞输注对于本例患儿造血干细胞植入、GVHD控制可能具有重要辅助作用。     

HLA不全相合无关供者或单倍体外周血干细胞移植治疗X连锁无丙种球蛋白血症

异基因造血干细胞移植是目前可治愈X连锁无丙种球蛋白血症（XLA）的唯一方法。该研究病例1为4岁男性患儿，行HLA不全相合无关供者外周血干细胞移植；病例2为儿童期起病的24岁男性患者，合并原发皮肤肢端CD8⁺T细胞淋巴瘤，行单倍体外周血干细胞移植。两者均采用减低毒性的清髓性预处理方案，并用后置环磷酰胺、兔抗人胸腺细胞免疫球蛋白、甲氨蝶呤和环孢素预防移植物抗宿主病（GVHD）。病例1+11?d（移植后为“+”）中性粒细胞及血小板均植入，+90?d供者嵌合下降，经供者淋巴细胞输注后于+150?d恢复。病例2移植后+20?d中性粒细胞植入，+87?d血小板植入，+30?d为完全供者嵌合。两患者的相关指标（IgG、IgM、IgA和外周血中CD19⁺B细胞比例）分别于移植后2个月内、1年余恢复正常。两患者均未发生急性GVHD，病例1供者淋巴细胞输注后出现局限性慢性皮肤GVHD，经治疗后好转。该研究首次报道采用HLA不全相合无关供者或单倍体外周血干细胞移植联合后置环磷酰胺方案，配合改进的预处理方案成功治疗2例XLA患者，为供者的选择提供了新的途径。     

异基因造血干细胞移植治疗儿童重型再生障碍性贫血

目的探讨异基因造血干细胞移植(allo-HSCT)治疗儿童重型再生障碍性贫血(SAA)的疗效及并发症。方法 4例SAA患儿,均接受氟达拉滨、环磷酰胺、抗胸腺细胞球蛋白预处理;其中3例患儿行HLA全相合同胞骨髓造血干细胞移植(BMT),1例患儿行HLA全相合同胞外周血造血干细胞移植(PBSCT)。同胞供者采集重组人粒细胞集落刺激因子5μg.kg-1.d-1,动员骨髓及外周血干细胞。采用环孢素+短疗程小剂量甲氨蝶呤方案预防移植物抗宿主病,前列腺素E预防肝静脉闭塞综合征,更昔洛韦预防巨细胞病毒感染,美司那及水化碱化预防出血性膀胱炎。通过DNA短串联重复序列多态性分析检测植入情况。结果 2例BMT患儿及1例PBSCT患儿完全植入;1例BMT患儿嵌合植入。中性粒细胞>0.5×109L-1中位时间12 d(9～15 d),血小板>20×109L-1中位时间19 d(12～30 d)。结论 allo-HSCT是治疗儿童SAA的有效方法,维持造血功能以及移植后并发症的发生及防治,仍是目前重点讨论的课题。     

后置环磷酰胺方案造血干细胞移植治疗9例湿疹血小板减少伴免疫缺陷综合征疗效分析

目的探讨后置环磷酰胺(PTCY)方案造血干细胞移植(allo-HSCT)治疗WAS的临床疗效。方法回顾性分析9例接受PTCY方案allo-HSCT治疗的WAS患儿的临床资料,包括移植前临床评分、供者情况、移植后粒细胞及血小板植入时间,移植后嵌合度及移植并发症。结果 9例患儿移植时中位年龄为15(4～108)个月,2例为同胞全相合供者,7例为半相合供者,回输移植物的单个核细胞中位数为15. 7(11. 3～27. 4)×10~8/kg,CD34+细胞中位数为9. 5 (4. 4～26. 1)×106/kg。中性粒细胞和血小板植入中位时间分别为14 (12～16) d和15 (11～29) d。中位随访时间为20(3～48)个月,所有病例均存活,仅1例患儿发生3度急性移植物抗宿主病(GVHD),无慢性GVHD,所有患儿移植后2周短串联重复序列结合聚合酶链反应(STR-PCR)检测显示为完全供者型嵌合。4例患儿发生巨细胞病毒血症,1例EB病毒血症,1例发生自身免疫溶血性贫血,3例发生免疫性血小板减少。结论 PTCY方案allo-HSCT可有效治疗WAS,该预处理方案无严重移植相关并发症,且无混合嵌合发生,并有效减少GVHD。     

双份脐带血移植治疗黏多糖贮积症临床疗效分析

目的了解黏多糖贮积症患儿非血缘异基因双份脐带血干细胞移植的疗效及特点。方法回顾性分析13例黏多糖贮积症患儿接受双份非血缘异基因脐带血干细胞移植的临床资料,包括受者情况、供者选取情况、移植后粒细胞及血小板植入时间、酶学指标、移植嵌合度及移植并发症情况。结果 13例患儿脐带血干细胞均顺利植活,其中单份植入10例,双份植入3例,此3例监测半年到一年,最终转为单份优势脐带血完全植入。移植后酶学检查均恢复正常,所有患儿均存活,发生Ⅰ度GVHD 2例,无慢性GVHD,4例发生巨细胞病毒血症,2例出现了BK病毒性膀胱炎,1例患儿发生了肾病综合征。结论双份脐带血干细胞移植是治疗大体重或单份脐血干细胞数量不足黏多糖贮积症患儿的有效治疗方法。     

肿瘤坏死因子基因多态性与儿童淋巴瘤关系的研究

目的利用SNaPshot SNP分型技术检测儿童淋巴瘤患者肿瘤坏死因子α(TNF-α)基因-308 G/A位点及淋巴毒素(LTα)基因+252 A/G位点的单核苷酸多态性(SNP),探讨TNF基因多态性与儿童淋巴瘤临床特征及预后的关系。方法收集2004年7月-2011年7月在我院血液科确诊的儿童淋巴瘤患者血样,提取基因组DNA,用SNaPshot SNP分型技术检测TNF-α基因-308G/A位点及LTα基因+252 A/G位点的单核苷酸多态性,分析TNF-α/LTα基因多态性与淋巴瘤患儿的临床特征及预后的关系。结果 62例淋巴瘤患儿中,非霍奇淋巴瘤51例,霍奇金病11例,TNF-α-308位点与LTα+252位点基因存在遗传连锁不平衡现象。将含2个及以上TNF或LTα高产位点的基因型定义为高危型,少于2个高产位点的基因型定义为低危型。对56例随访治疗的淋巴瘤患儿以Kaplan-Meier方法进行生存分析,高危型组和低危型组5年无事件生存率(EFS)分别为47%、75%(Log-rank检验,P=0.045),差异有显著性;对51例非霍奇金淋巴瘤患儿分析,高危型组和低危型组的5年EFS分别为53.5%、71.4%(Log-rank检验,P=0.288),差异无显著性。结论 TNF-α-308位点和LTα+252位点多态性联合危险度分型可能与儿童淋巴瘤预后有关。     

异基因造血干细胞移植治疗粘多糖病I型1例报告

目的：粘多糖病I型是一种进行性多器官受累的遗传代谢性疾病,Hurler综合征是粘多糖病I型的最严重类型,常导致进行性的中枢神经系统受损和早期死亡。该研究进行了异基因造血干细胞移植治疗该病的初步尝试,探讨异基因干细胞移植治疗粘多糖病的疗效。方法：1例男性粘多糖病I型Hurler综合征患者,2岁1个月,供者为其胞姐,HLA配型一个HLA-B位点不合。预处理方案为减低预处理剂量的BuCy方案马利兰(BU)每日3.7mg/kg,-9~-6d;环磷酰胺(Cy)每日42.8mg/kg,-5~-2d;抗胸腺细胞球蛋白每日3.5mg/kg,-7,-5,-3,-1d。输入重组人粒细胞集落刺激因子动员的供者CD34+细胞(12.8×106/kg),以环孢素A、骁悉、赛呢哌、抗胸腺细胞球蛋白和氨甲喋呤预防移植物抗宿主病(GVHD)。结果：移植后14d,短串联重复序列结合聚合酶链反应(STR-PCR)检测显示为完全供者型嵌合,中性粒细胞和血小板植活时间分别为+11d和+19d。仅出现肝、胃肠Ⅰ级预处理相关毒性,无严重预处理相关并发症。未发生急、慢性移植物抗宿主病和移植物衰竭,移植后临床症状明显改善,认知能力持续增加。结论：异基因造血干细胞移植治疗粘多糖病I型疗效肯定,减低剂量的预处理方案有利于降低预处理相关毒性;移植前后加强免疫抑制治疗,适当增加供者造血干细胞输注数量,有利于促进植入,减少移植物衰竭以及GVHD的发生。     

父供子单倍体异基因造血干细胞移植治疗高危白血病2例临床分析

目的探讨父供子单倍型造血干细胞移植治疗高危白血病的临床特点及疗效。方法对2例高危白血病接受父供子单倍型造血干细胞移植患儿的临床资料进行回顾性分析。结果 2例患儿回输有核细胞数分别为17.7×108/kg、8.3×108/kg,白细胞植活时间分别为+7 d和+16 d,血小板植活时间分别为+18 d和+8 d;2例均转为完全供者型;1例出现急性肠道GVHD(Ⅳ度),1例出现皮肤Ⅱ度GVHD;1例因移植后感染于+146 d死亡,1例存活,均无白血病复发倾向。结论非去T细胞性单倍型异基因造血干细胞移植正逐渐成为一种安全有效的治疗方法,为缺乏HLA完全相合相关或无关供者的高危难治性白血病患者提供了新的治疗选择。同时也提示父亲或父系抗原供者同样可以作为异基因造血干细胞来源。     

Engraftment and chimerism, particularly of T- and B-cells, in children undergoing allogeneic bone marrow transplantation

The spectrum of pediatric bone marrow transplantation has changed in recent years. Mismatched and unrelated donor transplants are common, demanding an increased vigilance to detect incipient graft failure, secondary lymphoma as well as relapse and other problems, which now are potentially treatable. To diagnose these complications it may be important to know whether blood and marrow cells are of recipient or donor origin. To evaluate the role of mixed donor-recipient chimerism in relation to clinical problems we adapted a polymerase chain-reaction technique, using fluorescent primers analyzing DNA fragment length polymorphisms, to follow prospectively 17 bone marrow grafted children. To increase the precision of chimerism analysis, immunomagnetically isolated leukocyte populations were assayed in selected cases. Five patients encountered clinical problems related to chimerism. One infant with adenosine deaminase deficiency failed to engraft stem cells, yet succumbed to graft-versus-host disease, mediated by mature donor T-cells. Three children developed significant mixed chimerism. One of these three patients died in relapse of leukemia, while the two other patients who had received T-cell depleted grafts had persistent recipient T-cells, in spite of engraftment. After 5 months, these were displaced by donor T-cells in one of the patients. In the fifth patient, also after T-cell depleted BMT, a fatal donor cell lymphoma occurred. Twelve children had stable full chimerism or in one case a low grade mixed chimerism and remain disease-free throughout follow up (median 9 months). In conclusion, the analysis of chimerism, particularly of separated leukocyte populations, offers an almost indispensable insight and a basis for therapeutic decisions in complicated situations such as grafting involving unrelated or mismatched donors, graft manipulation, adoptive immunotherapy and in immunodeficiency patients.     

Evaluation of chimerism by quantitative PCR analysis of DNA polymorphism after allogeneic hematopoietic stem cell transplantation in a pediatric population with malignancies

Relapse remains the major pitfall to success for Allo-HSCT in children with malignancies. Ninety-one patients undergoing Allo-HSCT were retrospectively reviewed. Chimerism status was evaluated at days +30, +60, and +100 in PB. VNTR-PCR and STR-PCR were used for this purpose. Thirty-one patients recurred (34%) and none survived. Thirty-two remain alive in CR (35%). Patients who achieved a CC at those days had a significant higher RFS and OS than patients who did not. Twelve patients showing PMC had an increased risk of recurrence (p=0.02. OR 7.7). In the univariate analysis, the probability of death was higher in patients who were not in first CR before transplant (p=0.008.OR 2.09) and in those receiving cells not from PB (p=0.002.OR 2.03). In the multivariate analysis, the absence of CC at day +100 was associated with a higher probability of relapse (p=0.004. OR 10.8) and death (p=0.016. OR 9.3). Serial chimerism PCR-based analyses of polymorphic DNA markers can predict relapse. Patients with PMC are at the highest risk of recurrence. Patients receiving an Allo-HSCT in first CR from PB who achieve a CC at day +100 have a better outcome.     

Megakaryocyte chimerism after allogeneic stem cell transplantation in children

The aim of this study was to investigate the extent and the clinical implications of mixed chimerism in megakaryocytes after stem cell transplantation (SCT). Polymerase chain reaction analyzing allele length polymorphisms was used to determine the origin of immunomagnetically isolated megakaryocytes and leukocyte subpopulations after SCT in 13 children. Eleven were unselected consecutive cases while two were included due to known leukocyte mixed chimerism. Recipient DNA was detected in the megakaryocytes in six out of the 11 cases at levels between 1 and 100%. Coinciding mixed chimerism in the leukocyte populations was detected in two of the 11 cases. Of the two selected cases with known leukocyte mixed chimerism, two boys with aplastic anemia and Wiskott-Aldrich syndrome had 1-5 and 70% recipient megakaryocytes, respectively. Although the four relapses or deaths, within the 13 months of observation, were restricted to patients with multilineage or isolated megakaryocyte (n = 1) mixed chimerism, it was not possible to link any other apparent clinical problems, except a prolonged thrombocytopenia in one case, to the mixed chimerism in this limited study group.     

Early mixed T‐cell chimerism is predictive of pediatric AML or MDS relapse after hematopoietic stem cell transplant

Patients with acute myeloid leukemia (AML) who relapse after hematopoietic stem cell transplantation (HCT) have dismal outcomes. Our ability to predict those at risk for relapse is limited. We examined chimerism trends post‐HCT in 63 children who underwent HCT for AML or myelodysplastic syndrome (MDS). Mixed T‐cell chimerism at engraftment and absence of chronic graft versus host disease (cGVHD) were associated with relapse (P = 0.04 and P = 0.02, respectively). Mixed T‐cell chimerism at engraftment was predictive in patients without cGVHD (P = 0.03). Patients with engraftment mixed T‐cell chimerism may warrant closer disease monitoring and consideration for early intervention.     

Chimerism of allogeneic mesenchymal cells in bone marrow,liver, and spleen after mesenchymal stem cells infusion

Although an infusion of culture‐expanded MSCs is applied in clinic to improve results of HSCs transplantation and for a treatment of musculoskeletal disorders, homing, and engraftment potential of culture‐expanded MSC in humans is still obscure. We report two female patients who received allogeneic BM transplantation as a treatment of hematological diseases and a transplantation of MSCs from third‐party male donors. Both patients died within one yr of infectious complications. Specimens of paraffin‐embedded blocks of tissues from transplanted patients were taken. The aim of the study was to estimate possible homing and engraftment of allogeneic BM‐derived MSCs in some tissues/organs of recipient. Sensitive real‐time quantitative PCR analysis was applied with SRY gene as a target. MSC chimerism was found in BM, liver, and spleen of both patients. We conclude that sensitive RQ‐PCR analysis is acceptable for low‐level chimerism evaluation even in paraffin‐embedded tissue specimens.     

Successful unrelated mismatched cord blood transplantation in an infant with severe combined immunodeficiency and Mycobacterium bovis bacillus Calmette-Guèrin disease

The case reported here of an infant who presented with Pneumocystis carinii pneumonia, CD4+ lymphopenia, and hypogammaglobulinemia attributable to severe combined immunodeficiency (SCID). This report discussed treatment of Mycobacterium bovis bacillus Calmette-Guèrin disease with unrelated cord blood transplantation in addition to antituberculous therapy, by adoptively transferring donor immunity with induction of mixed chimerism. Because of the unique nature of umbilical cord blood hematopoietic cells, engraftment without conditioning may be possible in SCID patients without fully matched donors.     

Higher doses of CD34+ PBPC are associated with a rapid acquisition of full donor chimerism and lower risk of relapse after allogeneic transplantation in pediatric patients with hematological malignancies

We conducted a retrospective study assessing the predictive value of early full donor chimerism status for relapse after allogeneic peripheral blood progenitor cell transplantation in 40 children aged between 1 and 16 years (median 8) with leukemia. The only variable that had a significant influence on chimerism status in either univariate or multivariate analysis was the number of CD34 cells infused. We found that the patients who were in complete donor chimerism by day +30 had a lower probability of relapse than those who were not (14% ± 6% versus 54% ± 15%; HR, 5.24; 95% confidence interval, 2.10-43.63; P = 0.003). Mixed chimerism by day +30, absence of chronic GvHD, and advanced disease at transplantation were significant risk factors for relapse in our patients. Children who presented early complete chimerism had a probability of developing chronic graft versus host disease significantly higher than patients with mixed chimerism (P = 0.04). Therefore, the analysis of chimerism kinetic in children undergoing peripheral blood progenitor cell transplantation would permit an early identification of patients at risk of relapse and patients with high risk of developing chronic graft versus host disease.     

Early mixed chimerism‐based preemptive immunotherapy in children undergoing allogeneic hematopoietic stem cell transplantation for acute leukemia

This retrospective analysis comprises 10‐year experience with early posttransplant mixed chimerism‐based preemptive intervention. Out of 104 patients, 51 received preemptive immunotherapy. Their outcomes were similar to patients achieving full donor chimerism spontaneously. Among patients receiving intervention, 5‐year event‐free survival was identical in patients with and without pretransplant residual disease, respectively (68% [95% confidence interval (CI) 38–98%] vs. 69% [95% CI 54–85%] log–rank = 0.4). In patients who received preemptive immunotherapy, chimerism status and residual disease prior to transplant were no longer predictors of poor outcome; however, 41% of the patients with residual disease prior to transplant relapsed early and did not benefit from this strategy.     

Unrelated donor cord blood transplantation for childhood severe aplastic anemia after a modified conditioning

Treatment of severe aplastic anemia (SAA) patients who lack human leukocyte antigen (HLA)-matched donors and failed immunosuppressive therapy (IST) is challenging. Recently, umbilical cord blood transplantation (CBT) after non-myeloablative therapy has been reported in adult but not in childhood SAA. However, most cases resulted in mixed donor chimerism and incomplete hematological recovery. We reported an 11-yr-old girl with recurred SAA 5 yr after IST who underwent unrelated donor CBT after a modified regimen. This patient had renal and cardiac dysfunction, and lacked suitable bone marrow donors. The 3.9 x 10(7)/kg CB cells from an HLA one-locus mismatched unrelated donor were infused after conditioning with total body irradiation (5 Gy), melphalan (120 mg/m(2)), and fludarabin (120 mg/m(2)). Hematological recovery was favorable in complete chimerism. A major complication was only skin graft-versus-host disease (grade I). CB could be an alternate stem cell source for childhood SAA after modified preparative regimen.