Spontaneous circulation of myeloid-lymphoid-initiating cells and SCID-repopulating cells in sickle cell crisis

The only curative therapy for sickle cell disease (SCD) is allogeneic hematopoietic stem cell (HSC) transplantation. Gene therapy approaches for autologous HSC transplantation are being developed. Although earlier engraftment is seen when cells from GCSF-mobilized blood are transplanted than when bone marrow is transplanted, administration of GCSF to patients with SCD can cause significant morbidity. We tested whether primitive hematopoietic progenitors are spontaneously mobilized in the blood of patients with SCD during acute crisis (AC-SCD patients). The frequency of myeloid-lymphoid-initiating cells (ML-ICs) and SCID-repopulating cells (SRCs) was significantly higher in blood from AC-SCD patients than in blood from patients with steady-state SCD or from normal donors. The presence of SRCs in peripheral blood was not associated with detection of long-term culture-initiating cells, consistent with the notion that SRCs are more primitive than long-term culture-initiating cells. As ML-ICs and SRCs were both detected in blood of AC-SCD patients only, these assays may both measure primitive progenitors. The frequency of ML-ICs also correlated with increases in stem cell factor, GCSF, and IL-8 levels in AC-SCD compared with steady-state SCD and normal-donor sera. Because significant numbers of ML-ICs and SRCs are mobilized in the blood without exogenous cytokine treatment during acute crisis of SCD, collection of peripheral blood progenitors during crisis may yield a source of autologous HSCs suitable for ex-vivo correction by gene therapy approaches and subsequent transplantation.     

亲缘异基因造血干细胞移植联合甲磺酸伊马替尼治疗Ph阳性白血病

背景：造血干细胞移植是可以治愈Ph＋白血病有效方法,甲磺酸伊马替尼是一种高度特异的酪氨酸激酶抑制剂,能抑制BCR/ABL酪氨酸激酶活性,在Ph＋白血病中的应用越来越多。目的：探讨甲磺酸伊马替尼联合亲缘异基因造血干细胞移植治疗Ph＋白血病的临床疗效。方法：回顾性分析2011年1月至2012年10月采用亲缘异基因造血干细胞移植联合甲磺酸伊马替尼治疗12例Ph＋白血病的疗效并文献复习。结果与结论：12例患者移植后均获得造血重建,移植后中性粒细胞和血小板植活的中位时间分别为15 d和18 d;发生Ⅱ度急性移植物抗宿主病7例,Ⅲ度急性移植物抗宿主病1例,局限型慢性移植物抗宿主病7例,广泛型慢性移植物抗宿主病3例;无白血病存活率为67%,移植相关死亡率为25%。行HLA匹配亲缘造血干细胞移植者的总体存活率为75.0%。平均无病生存8.5个月（7-17个月）,BCR/ABL转阴时间2-5个月。亲缘异基因造血干细胞移植前、后联合甲磺酸伊马替尼治疗Ph＋白血病,具有降低移植前白血病细胞负荷,抑制残留白血病细胞增殖,促进供者完全嵌合状态的转变,是一种安全有效的治疗方法。     

Allogenic hematopoietic stem cell transplantation in sickle cell disease

Sickle cell disease (SCD) is one of the most common monogenic disorders worldwide and affects approximately 100,000 people in the United States alone. SCD can cause numerous complications, including anemia, pain, stroke, and organ failure, which can lead to death. Although there are a few disease-modifying treatments available to patients with SCD, the only current curative option is a hematopoietic stem cell transplant (HSCT). In this review, we will discuss the different approaches to allogeneic HSCT in the treatment of SCD and the outcomes of these approaches.     

Gene therapy for hemoglobinopathies

Beta hemoglobinopathies such as sickle cell disease (SCD) and β-thalassemia (BT) are the most common monogenic diseases worldwide. Both diseases are associated with significant morbidity and mortality. Because patients require lifelong follow-up and care, it also poses a serious burden in health services. Blood transfusions and/or drug therapy ameliorate the signs and symptoms of the disorders but are not curative. Allogeneic hematopoietic cell transplantation (HCT) is currently the only cure but it has several limitations including the paucity of human leukocyte antigen-matched related donors and a high risk of adverse events. Recent advances in hematopoietic stem cell based-gene therapy has made autologous HCT (auto?HCT) a reality. Clinical trials are underway using different gene transfer vectors and cassettes. Data obtained so far with a short-term follow-up has been very encouraging. Patients with SCD engrafted, had sustained production of the transgene and a decreased number of vaso-occlusive crises. Patients with BT were able to decrease the amount of transfusions required or stop transfusions all together. Adverse events observed were mostly associated with the myeloablative conditioning regimen. Long term data on gene persistence and toxicities are still needed. This review focuses on the current state of auto?HCT with gene therapy for SCD and BT. Current clinical trials and their outcome results are summarized.     

Advances in the Treatment of Sickle Cell Disease

Sickle cell disease (SCD) is a monogenic disorder that afflicts approximately 100,000 Americans and millions of people worldwide. It is characterized by hemolytic anemia, vaso-occlusive crises, relentless end-organ injury, and premature death. Currently, red blood cell transfusion and hydroxyurea are the major disease-modifying therapies available for SCD. Hematopoetic stem cell transplant is curative, but barriers to treatment are substantial and include a lack of suitable donors, immunologic transplant rejection, long-term adverse effects, prognostic uncertainty, and poor end-organ function, which is especially problematic for older patients. Gene therapy to correct the β^s point mutation is under investigation as another curative modality. Deeper insights into the pathophysiology of SCD have led to the development of novel agents that target cellular adhesion, inflammation, oxidant injury, platelets and/or coagulation, vascular tone, and hemoglobin polymerization. These agents are in preclinical and clinical trials. One such agent, L-glutamine, decreases red blood cell oxidant injury and is recently US Food and Drug Administration approved to prevent acute pain episodes of SCD in patients 5 years of age or older. The purpose of this review is to describe the currently established therapies, barriers to curative therapies, and novel therapeutic agents that can target sickle cell hemoglobin polymerization and/or its downstream sequelae. A PubMed search was conducted for articles published up to May 15, 2018, using the search terms sickle cell disease, novel treatments, hematopoietic stem cell transplantation, and gene therapy. Studies cited include case series, retrospective studies, prospective clinical trials, meta-analyses, online abstracts, and original reviews.     

Graft failure after allogeneic hematopoietic stem cell transplantation

Graft failure is a serious complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT) defined as either lack of initial engraftment of donor cells (primary graft failure) or loss of donor cells after initial engraftment (secondary graft failure). Successful transplantation depends on the formation of engrafment, in which donor cells are integrated into the recipient’s cell population.In this paper, we distinguish two different entities, graft failure (GF) and poor graft function (PGF), and review the current comprehensions of the interactions between the immune and hematopoietic compartments in these conditions. Factors associated with graft failure include histocompatibility locus antigen (HLA)-mismatched grafts, underlying disease, type of conditioning regimen and stem cell source employed, low stem cell dose, ex vivo T-cell depletion, major ABO incompatibility, female donor grafts for male recipients, disease status at transplantation.Although several approaches have been developed which aimed to prevent graft rejection, establish successful engraftment and treat graft failure, GF remains a major obstacle to the success of allo-HSCT.Allogeneic hematopoietic stem cell transplantation (allo-HSCT) still remains to be the curative treatment option for various non-malignant and malignant hematopoietic diseases. The outcome of allo-HSCT primarily depends on the engraftment of the graft. Graft failure (GF), is a life-threatening complication which needs the preferential therapeutic manipulation. In this paper, we focused on the definitions of graft failure / poor graft function and also we reviewed the current understanding of the pathophysiology, risk factors and treatment approaches for these entities.     

What is the role of apheresis technology in stem cell transplantation?

Since the demonstration that hematopoietic cells are present in circulating blood, peripheral blood stem cell transplantation (PBSCT) has become an area of interest. The invention of growth factors such as the granulocyte colony-stimulating factor (G-CSF) and the availability of apheresis techniques allowed the wide application of peripheral blood stem cells (PBSC) in both autologous and allogeneic hematopoietic stem cell transplantation settings. It has been since 1986 that clinically introduced, peripheral blood stem cells replaced bone marrow as a stem-cell source to nearly 100% in the autologous and to approximately 75% in the allogeneic transplantation setting. During this period of time, remarkable development occurred in both stem cell mobilizing agents (i.e. CXCR4 antagonists) and apheresis techniques. Currently, apheresis technology is being increasingly used in not only for collection of PBSC or blood product support, but also for treatment and/or prevention of several transplantations related complications. Apheresis technology also allows to manipulate stem cells and thus provides opportunity to curative treatment of certain diseases.     

Umbilical cord blood as a hematopoietic stem cell source in transplantation for pediatric sickle cell disease: current challenges and strategies

Allogeneic hematopoietic stem cell transplant (HSCT) is the only established cure for sickle cell disease (SCD), a hemolytic disorder that arises due to a point mutation in the hemoglobin A gene. The result is an abnormal sickle hemoglobin (HbS) replacing hemoglobin A. Of the spectrum of sickle hemoglobinoapthies, homozygous (HbSS) and HbSβ⁰ thalassemia manifest severe forms of disease characterized by chronic endothelial injury/vasculopathy, ischemic pain, and vital organ damage that commence in childhood and escalate with age resulting in impaired quality of life, increased healthcare burden, and early mortality. HSCT has demonstrated durable disease control and regression of symptoms. Human leukocyte antigen (HLA) matched sibling donor (MSD) transplantation can achieve disease-free survival of > 90%. However, < 18% of SCD patients in the United States have a MSD. Familial mismatched and unrelated donors from registries provide alternate stem cell sources. Umbilical cord blood (UCB) from family or cord blood banks expand donor sources and are attractive due to donor-independent ease of use and availability. These naïve cells tolerate greater degrees of HLA-mismatch. The primary challenge with UCB is optimizing cell dose toward successful engraftment and timely immune reconstitution while minimizing graft-versus-host disease (GVHD). This review summarizes evidence that UCB remains a promising stem cell source where modern methods of graft expansion, conditioning, GVHD prophylaxis, and infection control can overcome these challenges and retain the value of this intervention.     

13例原发性系统性淀粉样变性患者行自体外周血造血干细胞采集的护理体会

目的探讨原发性系统性淀粉样变性（AL）患者行自体外周血造血干细胞采集中的护理要点。方法 13例AL患者在本科干细胞移植病房行自体外周血造血干细胞采集,所有患者均经肾活检明确诊断,采用单用粒细胞刺激因子（G-CSF）方案采集干细胞,人均采集2次。结果所有患者均成功采集足够干细胞,主要并发症为低钙血症、低钾血症及血小板减低。采集CD34＋细胞数（2.00~8.36）×106/kg,平均（4.02±2.01）×106/kg。结论对于严格选择的AL患者,自体外周血干细胞移植（AHSCT）治疗是一种有效的治疗手段,采集足量的造血干细胞是成功行干细胞移植的重要前提。     

低强度预处理异基因造血干细胞移植治疗骨髓增生异常综合征研究进展

异基因造血干细胞移植（allo—HSCT）是治疗骨髓增生异常综合征（MDS）的有效手段，MDS发病率随年龄增加而增加，尽管近年来传统清髓性移植治疗MDS取得可喜的成绩，但对于年龄大于60岁的MDS患者，allo—HSCT预后差，低强度预处理异基因造血干细胞移植（RIC allo—HSCT）使老年MDS患者进行allo—HSCT成为可能，利用供者淋巴细胞的移植物抗肿瘤作用显著降低移植相关器官毒性及非复发死亡率．本文就RIC—HSCT治疗MDS的问题诸如RIC allo—HSCT治疗MDS可行性，MDS病例选择，RIC allo—HSCT的时机干细胞来源，RIC预处理方案．疗效及预后评价．GVHD与移植物抗MDS效应等的研究进展做一综述及展望。     

Transfer of hematopoietic stem cells encoding autoantigen prevents autoimmune diabetes

Bone marrow or hematopoietic stem cell transplantation is a potential treatment for autoimmune disease. The clinical application of this approach is, however, limited by the risks associated with allogeneic transplantation. In contrast, syngeneic transplantation would be safe and have wide clinical application. Because T cell tolerance can be induced by presenting antigen on resting antigen-presenting cells (APCs), we reasoned that hematopoietic stem cells engineered to express autoantigen in resting APCs could be used to prevent autoimmune disease. Proinsulin is a major autoantigen associated with pancreatic beta cell destruction in humans with type 1 diabetes (T1D) and in autoimmune NOD mice. Here, we demonstrate that syngeneic transplantation of hematopoietic stem cells encoding proinsulin transgenically targeted to APCs totally prevents the development of spontaneous autoimmune diabetes in NOD mice. This antigen-specific immunotherapeutic strategy could be applied to prevent T1D and other autoimmune diseases in humans.     

Review/overview of pain in sickle cell disease

Sickle cell disease (SCD) is a highly complex inherited disorder of hemoglobin structure. Although the molecular lesion is a single-point mutation, the sickle gene is pleiotropic in nature causing multiple phenotypic expressions that constitute the various complications of the disease. Its manifestations could be acute, chronic, nociceptive, neuropathic that could occur singly or in various combinations. Pain continues to be the major factor of SCD phenotypic complications and the most common cause of admissions to the Emergency Department and/or the hospital. Although progress has been made in understanding the pathophysiology of SCD as well as in developing curative therapies such as hematopoietic stem cell transplantation and gene therapy, effective pain management continues to lag behind. Palliative therapies continue to be the major approach to the management of SCD and its complications. The advent of hydroxyurea made partial success in preventing the frequency of vaso-occlusive crises and l-glutamine awaits post-trial confirmation of benefits. The search for additional pharmacotherapeutic agents that could be used singly or in combination with hydroxyurea and/or l-glutamine awaits their dawn hopefully in the near future. The purpose of this review is to describe the various manifestations of SCD, their pathophysiology and their current management. Recent impressive advances in understanding the pathophysiology of pain promise the determination of agents that could replace or minimize the use of opioids.     

异基因造血干细胞移植治疗进展期慢性髓系白血病疗效及预后的初步分析

加速期和急变期慢性髓系白血病(CML)患者预后较差,异基因造血干细胞移植(allo-HSCT)是这一类患者唯一具有治愈可能的治疗方法。本研究探讨allo-HSCT治疗进展期CML的疗效及预后。对1998年9月至2008年1月28例接受allo-HSCT的患者从疗效、移植前基础特点与预后、移植前治疗策略与预后、移植后事件与预后等方面进行了回顾性分析。结果表明:28例患者中10例活存并持续缓解,3年总活存率和无病活存率分别34.9%和35.7%;18例死亡。单因素分析发现,克隆演进和原始细胞比例是预后不良的基线危险因素,二者结合可以预测预后。移植前应用伊马替尼并取得完全血液学缓解并不能改善预后。对移植后事件的预后分析发现,并发重度移植物抗宿主病是预后不良的危险因素。结论:对于接受allo-HSCT治疗的进展期CML病例,克隆演进和原始细胞比例是具有预后意义,移植前应用伊马替尼并不能改善预后。     

DEFECTS IN HEMATOPOIETIC DIFFERENTIATION IN NZB AND NZC MICE

Hematopoietic stem cell activity in inbred NZB and NZC mice has been determined by transplantation and endogenous spleen colony assays. Whereas NZB mice show normal colony-forming unit (CFU) activity in the transplantation assay, they show markedly elevated endogenous CFU. NZC mice also show this markedly elevated endogenous CFU activity, but in the transplantation assay show only about 5–10% of normal CFU counts. When NZC stem cells are tested for CFU activity in irradiated recipients of the H-2^d type, almost normal colony numbers occur. NZB stem cells however also cannot form colonies in NZC mice. These results suggest that NZC mice have a defect in the micro-environment of the spleen which renders them incapable of allowing transplanted CFU to form colonies. Genetic analysis of both the NZC defect as a CFU recipient, and the elevated endogenous count in NZB and NZC, shows that both are controlled by single recessive genes which are not linked to either coat color, agouti, H-2 or Ig loci. Of even more relevance is the finding that these hematopoietic abnormalities are not linked to the genes involved in controlling autoantibody formation to red cells in the NZB mice. These mice therefore appear to show two distinct hematopoietic abnormalities, the analysis of which may be of considerable value in understanding the detailed events of hematopoietic stem cell differentiation.     

猕猴单倍体相合非清髓造血干细胞联合间充质干细胞移植的实验研究

目的 用非清髓预处理建立猕猴单倍体相合造血干细胞移植(HSCT)模型，研究间充质干细胞(MSC)在单倍体相合移植中的作用。方法采用健康、单倍体相合的猕猴亲子配对，受非清髓性预处理用氟达拉滨 环磷酰胺 ^60Co(200cGy)全身照射 兔抗人胸腺细胞球蛋白，移植物抗宿主病(GVHD)预防用环孢菌素A、霉酚酸酯、抗CD25单抗。实验分为单纯造血干细胞(HSC)移植组和HSC联合MSC移植组；检测供受体嵌合水平，观察造血恢复、GVHD等情况。结果单倍体相合的子代猕猴采用非清髓预处理方案，可获稳定植入?比较了单纯非清髓HSC移植组和HSC联合MSC移植组的造血恢复，发现造血恢复时间主要与嵌合状态有关；MSC可促进植入；相同条件下，HSC联合MSC移植组更容易形成供受混合嵌合；GVHD的发生率低。结论成功建立了猕猴非清髓性单倍体相合HSCT的模型，非清髓HSCT联合MSC可能在单倍体相合移植中有较好效果。     

Is there a “gold” standard treatment for patients with isolated myeloid sarcoma?

Isolated myeloid sarcoma is an extramedullary tumor of immature myeloid cells defined by the absence of leukemia history, myelodisplastic syndrome, or myeloproliferative neoplasma with a negative bone marrow biopsy. Myeloid sarcoma is a very rare condition, and few cases have been reported. We reviewed data of 12 patients with isolated myeloid sarcoma managed at a single center to determine the possible prognostic factors affecting patient survival, such as age, sex, type, localization, and treatment options. Patients were mostly men (n = 8), with a median age of 39 years. Patients were initially treated with chemotherapy (n = 7) or surgery (n = 5). In three patients, hematopoietic stem cell transplantation was performed. During the follow-up period, nine patients died. The median overall survival was 13 months, while event-free survival was 8 months. Regarding initial treatment strategy, no significant difference in overall survival was observed. Both chemotherapy and hematopoietic stem cell transplantation independently improved event-free survival. In addition, patients who received chemotherapy combined with hematopoietic stem cell transplantation had significantly longer event-free survival than those treated with chemotherapy alone. Age < 40 years together with chemotherapy/hematopoietic stem cell transplantation significant affected event-free survival. Based on our results, the treatment of myeloid sarcoma requires a systemic rather than a localized approach with surgery or radiotherapy. While prospective evaluations are needed, chemotherapy with allogenic hematopoietic stem cell transplantation should be considered as the optimal therapy for isolated myeloid sarcoma.     

HLA不全相合造血干细胞联合脐血移植治疗急性白血病的临床观察

目的观察HLA不全相合造血干细胞联合脐血移植治疗急性白血病的有效性及安全性。方法 2008年6月～2010年12月本科20名急性白血病患者接受HLA不全相合造血干细胞联合脐血移植,和同期进行的HLA不全相合造血干细胞移植的51名急性白血病患者,进行造血重建、植入,移植相关并发症和疗效方面的比较。结果联合移植组平均输入脐血有核细胞数2.96×107/kg,CD34+细胞2.99×105/kg;1名患者未植入,ANC≥0.5×109/L的平均时间为12.6±2.50 d,Plt≥20×109/L的平均时间为17.2±3.70 d和对照组均无显著差异(P0.05);植入检查均为完全供者型;联合移植组Ⅲ～Ⅳ度的严重aGVHD的发生率为5.0%显著低于对照组的11.7%(P0.05);1年OS联合移植组为80%优于对照组的72.5%(P0.05);两组间cGVHD发生率、复发率和感染并发症的比较无统计学意义(P0.05)。结论 HLA不全相合造血干细胞联合脐血移植降低严重aGVHD的发生率,提高长期生存率,是对HLA不全相合造血干细胞移植方法的改良,临床应用安全有效。     

造血干细胞移植与自身免疫性疾病

目的：认识造血干细胞移植治疗自身免疫性疾病的历史发展及其机制，讨论治疗过程中关于疗效和安全性的相关问题。 方法：检索Pubmed数据库和中国期刊全文数据库文献，然后对资料进行初审，并查看每篇文献后的引文。纳入标准：文章所述内容为造血干细胞移植治疗自身免疫性疾病的机制和应用研究：以近5年且发表在较权威杂志者优先。排除标准：重复研究或Meta分析类文章。 结果：①造血干细胞移植最早用于治疗血液恶性肿瘤，随着临床医学的发展，其适应证逐步扩展至血液系统疾病、自身免疫性疾病、实体瘤和基因缺陷疾病等。②目前认为造血干细胞移植治疗自身免疫性疾病的作用，主要是建立在大剂量免疫抑制剂对原有免疫系统的清除作用基础上造血干细胞移植后的免疫重建。③造血干细胞移植治疗自身免疫性疾病的疗效与安全性各不相同，与病种、病例的选择、预处理方案有关。 结论：①造血干细胞移植治疗自身免疫性疾病尚未确定可获得长期安全稳定临床效应的最佳移植方案。总体认为造血干细胞移植近期疗效显著，而远期疗效尚需多中心、多病例的临床研究和观察，以进一步探讨其安全性和有效性。②只有在真正实现移植后的免疫重建，控制移植后复发，最终才能达到通过造血干细胞移植治愈自身免疫性疾病。