SIBLING DONOR CORD BLOOD BANKING FOR CHILDREN WITH SICKLE CELL DISEASE

Although hematopoietic stem cell transplantation has curative potential for selected patients with sickle cell disease (SCD), most patients who are eligible for transplantation do not have a suitable donor. Cord blood (CB) from a sibling could provide an alternative stem cell source that, while not as well established as marrow, may offer certain advantages for selected families. These potential advantages include low risk to the infant donor, the possibility that mismatched CB units from sibling donors may be acceptable for transplantation, prompt availability of a stored CB unit for transplant, and decreased risk of clinically significant graft-versus-host disease. When families with SCD (or other transplant-treatable condition) conceive a sibling, no comprehensive research resource exists to assist the family in collecting the new infant's CB. With support from the National Heart Lung and Blood Institute, we are developing a noncommercial research-based CB Banking Program specifically for medically indicated sibling donations. In preliminary experience, we have collected CB from 52 SCD families across 19 states. Of these, 2 CB units have thus far been used for transplantation and 9 others are HLA-identical. We conclude that a CB bank focusing on sibling-donations may be feasible, but further study is required to determine whether such a bank can collect CB units of sufficient quantity and quality to support controlled trials of sibling CB transplantation. Families with a specific medical need, such as those already caring for a child with SCD, should consider collecting sibling CB as part of comprehensive care if the opportunity becomes available.     

New approaches to hematopoietic cell transplantation for hematological diseases in children

Hematopoietic cell transplantation (HCT) has been used for more 30 years for the treatment of selected malignant and nonmalignant diseases. Traditionally, HCT for hematological disorders has relied on myeloablative conditioning before HLA-identical sibling bone marrow transplantation to correct the underlying hematological defect. Most children with hematological diseases who are referred to HCT have features that portend significant morbidity and early mortality. Among SAA patients who have HLA-identical sibling donors, younger patients with profound pancytopenia might be considered early for HCT. For others who lack sibling donors, patients who receive HCT from alternate sources have generally failed one or more courses of intensive immunosuppressive therapy and remain transfusion-dependent, some with hemosiderosis, red cell alloimmunization, and platelet transfusion refractoriness [44,46,48]. Currently, HCT for SCD is generally restricted to those who have experienced a significant sickle-related complication such as stroke, recurrent acute chest syndrome, or recurrent painful episodes [7,13]. In contrast, most reserve HCT in thalassemia for younger, Lucarelli class I, good-risk patients who have HLA-identical sibling donors, and veer away from older, high-risk thalassemics for whom transplantation is a riskier clinical intervention. For groups such as young adults with thalassemia major, HCT might become more widely applicable if its toxicity was reduced. Several approaches undergoing development include reduced-intensity conditioning and attempts to prevent GVHD. New methods to reduce the intensity and toxicity of conditioning as well as to use highly purified stem cells with the reduction in graft versus host disease may allow for the use of matched unrelated donors or haploidentical donors. This would serve to provide potentially more children who could benefit from stem cell transplantation with donors. These advances will hopefully lead to benefits for the majority of children who lack HLA-identical donors.     

Hyperacute graft-vs.-host disease after related HLA-identical umbilical cord blood transplantation

haGVHD has been described following bone marrow and peripheral blood stem cell transplantation and in a single case who received unrelated HLA mismatched CB. An unusual case of haGVHD following HLA 6/6-matched sibling CBT in a child with AML is presented. The development of haGVHD in a fully matched CBT and without precipitating factors may suggest the role of still undefined and perhaps individual contributory factors.     

Analysis and characterization of hematopoietic progenitor cells from fetal bone marrow, adult bone marrow, peripheral blood, and cord blood.

Hematopoietic stem cell transplantation has been increasingly used to replace a defective hematopoietic system and to treat various genetic defects as well as malignant diseases. However, the limitations of conventional bone marrow transplantation have stimulated an intense interest in exploring the use of alternative sources of hematopoietic stem cells, including peripheral blood mononuclear cells (PBMC) and cord blood (CB). A major investigative effort of our laboratory has been focused on evaluating fetal bone marrow (FBM) for transplantation. The current study compares and characterizes the functional and phenotypic characteristics of FBM, CB, adult bone marrow (ABM), and PBMC by clonogenicity assays, immunogenicity, and the quantification of progenitor cells. There was a striking difference in the proportion of CD34+ cells in FBM, ABM, PBMC, and CB (24.6%, 2.1%, 0.5%, and 2.0%, respectively). The clonogenic potential, as measured by colony forming unit in culture (CFU-C) assay, was significantly higher in FBM when compared with ABM, PBMC, and CB (202.5, 73.5, 40.8, and 65.5 colonies/10(5) cells, respectively). There was a significant decrease in proliferative responsiveness in mixed lymphocyte reaction (MLR) assay of FBM and CB compared with ABM and PBMC. These observations indicate that each source of hematopoietic stem cells has different intrinsic properties closely correlated with ontogenetic age that is a vital determinant for phenotypic characteristics, lineage commitments, immunogenicity, and proliferative potentials.     

HLA全相合同胞骨髓移植术后早期并发自身免疫性溶血性贫血1例报告并文献复习

目的 报道1例重型地中海贫血（TM）患儿行HLA全相合同胞骨髓造血干细胞移植（HSCT）术后早期并发自身免疫性溶血性贫血（AIHA）的临床特点、治疗及随访,提高对该并发症的认识.方法 回顾性分析深圳市儿童医院血液肿瘤科1例TM患儿的临床资料,复习国内外相关文献.结果 重型β-TM患儿行HLA全相合同胞骨髓HSCT术后15 d出现血红蛋白进行性下降,伴乳酸脱氢酶及间接胆红素升高,间接抗人球蛋白试验阴性,直接抗人球蛋白试验IgG阳性、C3d阴性,应用糖皮质激素联合其他免疫抑制剂的治疗效果明显.结论 HSCT术后并发AIHA的主要发生机制可能有多重因素,加强HSCT术后AIHA发病机制的研究,将有利于该并发症的防治和改善预后.     

非血缘相关骨髓移植治疗重型地中海贫血的临床研究

目的为进一步拓展供髓源,探讨非血缘相关骨髓移植治疗重型地中海贫血(简称地贫)的可行性。方法9例地贫患儿进行了非血缘骨髓移植,其基因突变类型为地贫纯合子或双重杂合子,均确诊为重型β地贫。HLA高分辨配型全相合2例,1个亚型不合5例,2个亚型不合2例,6例红细胞血型不合。预处理为白消安16mg/kg,分4天口服;环磷酰胺200mg/kg,分4天静滴;抗人胸腺细胞免疫球蛋白30mg/kg,分3天静滴和氟达拉宾125mg/m2,分3天静滴。环孢素A和氨甲蝶呤预防移植物抗宿主病(graftversushostdisease,GVHD)。结果9例患儿均出现明显的过敏反应,1例有一过性低血压,皮肤急性GVHD7例,肝脏GVHD1例,肠道GVHD2例,慢性GVHD1例,高血压脑病1例,间质性肺炎2例。1例急性肺出血死亡。外周血中性粒细胞>0.5×109/L的时间为12～26天,WBC恢复正常的时间为23～110天,PLT于61～142天>50×109/L,Hb则于23～116天升至100g/L,最后一次输血时间为13～62天。PCR扩增短串联重复序列检测证实:8例患儿获得完全供体植入,1例未植入。随访6～24个月,7例原重型β地贫基因已消失,5例血型不合者已转成供者相同血型;7例患儿术后无需输血,Hb维持在110g/L以上。结论本组9例重型地贫的非血缘骨髓移植为国内首次尝试,初步证明非血缘骨髓移植根治重型地贫较安全可靠,为解决本病移植治疗的供髓源提供了新途径。     

Successful cord blood transplantation for sickle cell anemia from a sibling who is human leukocyte antigen-identical: implications for comprehensive care

We report the successful transplantation of umbilical cord blood stem cells from a sibling who is human leukocyte antigen-matched to a child with sickle cell anemia. Conditioning was with busulfan, cyclophosphamide, and antithymocyte globulin. Time to neutrophil count >500/microL was 23 days and to platelet count >50,000/microL was 49 days. Full donor engraftment was achieved without graft-versus-host disease. This case demonstrates the potential usefulness of harvesting cord blood from full siblings of patients with sickle cell disease. Routine collection of umbilical cord blood from siblings should be considered for patients with sickle cell disease, and may increase acceptance and use of transplantation by families.     

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。     

Ethical considerations of using a single minor donor for three bone marrow harvests for three HLA‐matched siblings with primary immunodeficiency

Allogeneic hematopoietic stem cell transplantation is curative for primary immunodeficiencies. Bone marrow from an unaffected human leukocyte antigen (HLA)‐identical sibling donor is the ideal graft source. For minor donors, meaningful consent or assent may not be feasible, and permission from parents or legal guardians is considered acceptable. Adverse events, albeit extremely small, can be associated with bone marrow harvest in pediatric donors. Donor safety concerns potentially increase with multiple bone marrow harvests. Very little is known about multiple bone marrow harvests from pediatric donors. We describe the ethical considerations and clinical decision‐making in an unusual clinical situation where three patients with the same primary immunodeficiency were HLA identical to one another and their younger sibling, who underwent bone marrow harvests three times between 1.3 and 4 years of age, resulting in successful transplantation for all three patients. We hope that this experience will provide guidance to providers and families in a similar situation.     

单倍体造血干细胞移植治疗儿童重型β-地中海贫血

目的：目前仅有30％左右的重型β-地中海贫血患者能找到HLA全相合的同胞供者,使造血干细胞移植治疗该病受到限制。该研究通过探讨单倍体造血干细胞移植治疗儿童重型β-地中海贫血的疗效,希望能够拓展供者源。方法：采用单倍体脐血或骨髓对10例重型β-地中海贫血患儿进行11例次移植。使用以羟基脲、氟达拉滨、白消安、环磷酰胺、抗胸腺细胞球蛋白为基础的预处理方案。结果：6例患者获长期稳定植入并脱离红细胞输注;2例短暂植入后排斥,其中1例恢复地中海贫血状态,另1例在移植早期死亡;1例行2次移植均未植入并出现移植后再障;1例未植入,出现再障,1年后恢复地中海贫血状态。8例植入者均发生急性移植物抗宿主病,仅1例发展为皮肤局限性慢性移植物抗宿主病。随访57.1（2.5～85.1）月,总体生存率90%,无病生存率为60%。结论：单倍体造血干细胞移植治疗儿童重型β-地中海贫血能长期重建造血,在无HLA相合同胞供体时,可以作为造血干细胞移植治疗的一种选择。［中国当代儿科杂志,2009,11（7）：546-548］     

Diagnosis and management of childhood aplastic anaemia

Aplastic anaemia (AA) is a rare and heterogeneous disorder. AA results in pancytopenia and a hypocellular bone marrow in the absence of an abnormal infiltrate, major dysplasia or marrow fibrosis. In children, most cases are idiopathic and caused by T lymphocyte-mediated destruction of haemopoietic stem and progenitor cells (HSPC's). Inherited bone marrow failure syndromes (IBMFS) account for around 20% of cases and have to be excluded. This can be challenging but has specific implications for management. Haemopoietic stem cell transplantation (HSCT) is the only definitive curative treatment for AA. For patients less than 35 years old with severe aplastic anaemia (SAA), a matched sibling donor (MSD) haematopoietic stem cell transplant is the treatment of choice. For those lacking such a donor, immunosuppressive therapy (IST) with antithymocyte globulin (ATG) and ciclosporin has historically been initial treatment. Improved outcomes following matched unrelated donors (MUD) transplantation has led to UK guidelines recommending upfront MUD HSCT in children and young adults where a suitable donor can be quickly identified. Recent advances in the treatment of patients with AA have shown that horse ATG with cyclosporine remains the current standard IST. The thrombopoietin receptor agonist eltrombopag has significant activity as a single agent and in combination with IST as initial treatment and in refractory patients. For patients with IBMFS, transplantation remains the only curative procedure.     

HLA‐matched family hematopoetic stem cell transplantation in children with beta thalassemia major: The experience of the Turkish Pediatric Bone Marrow Transplantation Group

Yesilipek MA, Ertem M, Cetin M, Öniz H, Kansoy S, Tanyeli A, Anak S, Kurekci E, Hazar V. HLA‐matched family hematopoetic stem cell transplantation in children with beta thalassemia major: The experience of the Turkish Pediatric Bone Marrow Transplantation Group. Abstract: From January 1991 to June 2009, 245 children with beta thalassemia major who underwent their first allogeneic HSCT in Turkey and who were followed for a minimum of one yr post‐transplantation were enrolled this study. The median age of the patients was 6.6 yr old (range, 1–22 yr). The distribution of Pesaro risk class I, II, and III categories was 41, 130, and 63 children, respectively. The median serum ferritin level was 2203 ng/mL. Eighty‐eight patients received bone marrow (BM) stem cells; 137, peripheral blood (PB) stem cells; and 20, cord blood (CB) stem cells. The donors were HLA‐matched siblings or parents. Median engraftment times were shorter in PBSCT patients compared with the BMT group (p < 0.001). Grade II‐IV acute GvHD was observed in 33 children (13.5%), while cGvHD was observed in 28 patients (12.5%), eight of whom had the extensive form. Thalassemic reconstitution was observed in 43 (17%) of the transplant patients. Post‐transplant aplasia occurred in three patients, and the TRM rate was 7.75%. Seventeen patients were lost after 100 days. The thalassemia‐free survival and OS rates were 68% (95% CI, 61.8–74.2) and 85.0% (95% CI, 80.2–89.8), respectively. We believe that this study is important because it is the first multicenter national data for children with beta thalassemia major receiving HSCT.     

CHILDHOOD LIPOSARCOMA: A Single-Institutional Twenty-Year Experience

Allogeneic bone marrow transplantation has proved to be a radical form of cure in patients with beta-thalassemia major who have a human leukocyte antigen identical donor. Although malignant neoplasms are serious late complications of bone marrow transplantation, very few reports describing the development of malignant tumors after allografting for thalassemia appeared in the literature. A case is presented here of extraosseous Ewing's sarcoma that developed 8 years after allogeneic bone marrow transplantation performed for beta-thalassemia major. The phenotypic features of the patient's family fullfill the criteria for Li-Fraumeni syndrome. The patient was treated with chemotherapy and radiotherapy and died with recurrent disease. To the authors' knowledge, this is the first case of extraosseous Ewing's sarcoma after bone marrow transplantation for thalassemia. The possible contribution of transplantation procedure and the genetic factors as well as the primary genetic hemoglobinopathy to the development of this malignant tumor are discussed.     

A case with extraosseous Ewing's sarcoma: a late effect related to bone marrow transplantation for thalassemia or a component of a familial cancer syndrome?

Allogeneic bone marrow transplantation has proved to be a radical form of cure in patients with beta-thalassemia major who have a human leukocyte antigen identical donor. Although malignant neoplasms are serious late complications of bone marrow transplantation, very few reports describing the development of malignant tumors after allografting for thalassemia appeared in the literature. A case is presented here of extraosseous Ewing's sarcoma that developed 8 years after allogeneic bone marrow transplantation performed for beta-thalassemia major. The phenotypic features of the patient's family fullfill the criteria for Li-Fraumeni syndrome. The patient was treated with chemotherapy and radiotherapy and died with recurrent disease. To the authors' knowledge, this is the first case of extraosseous Ewing's sarcoma after bone marrow transplantation for thalassemia. The possible contribution of transplantation procedure and the genetic factors as well as the primary genetic hemoglobinopathy to the development of this malignant tumor are discussed.     

造血干细胞移植治疗儿童白血病若干问题

该文涉及各类儿童造血干细胞移植(HSCT),如骨髓移植(BMT)、外周血造血干细胞移植(PBSCT)和脐血移植(UCBT)治疗白血病的优缺点及HSCT在儿童白血病治疗中的地位。绝大多数儿童白血病可通过正规联合化疗根治,仅少数(约20%)高危、难治及复发的白血病是异基因HSCT的适应证,无适合的同胞供体时,可选择HLA全相合非血缘相关BMT或PBSCT,UD-UCBT更适合于儿童患者。     

Allogeneic bone marrow transplantation for thalassemia in Taiwan: factors associated with graft failure

Fourteen thalassemia patients (aged 1.6-13.5 years; median age of 6 years) underwent allogeneic bone marrow transplantation (BMT) between March 1984 and May 1987. The preconditioning regimens consisted of oral busulfan, intravenous cyclophosphamide, with or without irradiation. Two of the patients, who received maternal transplants, failed to engraft but experienced autologous recovery. Of the 12 patients who received sibling marrow, two experienced autologous recovery and one developed marrow chimerism. Five patients died of complications of bone marrow transplantation: two died of intracranial hemorrhage, two died of sepsis, and one succumbed to acute graft-versus-host disease associated with cytomegalovirus infection. Six patients engrafted and have been followed for 1-4 years (median of 2.6 years) without intoward events. The overall survival rate was 64% (nine out of 14) with follow-up of 1-4 years. These results demonstrate that bone marrow transplantation can cure thalassemia but infection, graft-versus-host disease, and hemorrhage were major causes of morbidity and mortality in this group of patients. Other factors of importance include the unfavorable influence of engraftment of prior multiple transfusions and sex-mismatched transplantation. In patients who fail to engraft, autologous recovery usually occurs within 2 months of transplantation.     

Successful report of reduced-intensity stem cell transplantation from unrelated umbilical cord blood in a girl with chronic active Epstein-Barr virus infection

We describe an 8-year-old girl with chronic active Epstein-Barr virus (EBV) infection (CAEBV) who was treated successfully by reduced-intensity stem cell transplantation (RIST) from unrelated cord blood (CB). She had been suffering from fever, abdominal pain, and interstitial lymphadenopathy, and CAEBV was diagnosed. After chemotherapy that included etoposide, the amount of EBV decreased transiently below the detection level. However, the disease due to CAEBV worsened despite the chemotherapy, and she finally needed chemotherapy every week. Therefore, instead of conventional myeloablative transplantation, we performed CB transplantation with reduced-intensity conditioning regimens consisting of low-dose total body irradiation, fludarabine, and etoposide. CB, for which human leukocyte antigen (HLA) was 2-loci mismatched on the DR loci from an unrelated donor, was infused after conditioning. Although grade III acute graft-versus-host disease (GVHD) in the gut and chronic GVHD in the lung developed, the symptoms of GVHD disappeared with immunosuppressive therapy. After 15 months, the patient remained a complete chimera, with undetectable levels of EBV in peripheral blood and bone marrow. We conclude that RIST from unrelated CB can be indicated for some cases of CAEBV who are refractory to chemotherapy and have no HLA-matched related and unrelated donors as the source of bone marrow or peripheral blood stem cells.     

Stem cell transplantation for hemoglobinopathies

Hereditary anemias caused by beta-thalassemia and sickle cell disease are the most common genetic diseases worldwide. Supportive therapies such as chronic lifelong transfusions, iron chelation for thalassemia, and transfusions or hydroxyurea for sickle cell anemia have significantly ameliorated clinical manifestations of these diseases but cannot eliminate disease and treatment-related complications that result in end-organ damage. Allogeneic hematopoietic stem cell transplantation is the only cure for patients with hemoglobinopathies. Results of transplants have steadily improved over the last few decades due to effective control of transplant-related complications and development of new preparative regimens. Our understandings of mixed chimerism in patients with hemoglobinopathies provide a rationale for the use of less intensive conditioning regimens and gene therapy in these disorders. Although the role of stem cell transplantation for thalassemia major is well defined, few transplants have been carried out in sickle cell disease, and, in light of recent advances, the role of stem cell transplantation in this disease should be revised. This review summarizes the current status of stem cell transplantation for hemoglobinopathies.     

Rare complications after second hematopoietic stem cell transplantation for thalassemia major

We describe an 11-year-old girl with thalassemia major who underwent a second hematopoietic stem cell transplantation from a matched related donor and who subsequently developed posttransplant lymphoproliferative disorder complicated by severe ascending paralysis resembling Guillian-Barré syndrome. Six months later she developed a massive pericardial effusion. She received a multimodal treatment for these complications and currently, 18 months after transplantation, she is in a good clinical condition, is transfusion independent, with no evidence of graft-versus-host disease and off all treatment. This case highlights the dilemma surrounding second hematopoietic stem cell transplantations in hemoglobinopathies and the need for a careful, well informed, and collaborative decision-making process by patients, families, and medical professionals.     

Bone marrow transplantation: it's not just about blood anymore!

Abstract: Bone marrow transplantation is established as effective cell therapy for hematopoietic disorders. With the recognition that bone marrow also contains mesenchymal stem cells, with the potential to differentiate to a wide variety of mesenchymal tissues, bone marrow transplantation, in theory, may be used to treat many nonhematopoietic disorders as well. Here, we present an overview of the developments of clinically oriented marrow mesenchymal stem cell biology and it's early applications as adjunct cell therapy in conventional stem cell transplantation, and most importantly as stem cell therapy for nonhematopoietic disorders.