HLA单倍体相合与全相合外周血造血干细胞移植后的急性移植物抗宿主病

背景：异基因外周血造血干细胞移植成为造血干细胞移植的主要方式,近年来HLA单倍体相合造血干细胞移植因供者来源广泛在临床应用较多,急性移植物抗宿主病仍是影响移植成功率的主要因素。 目的：观察亲缘HLA单倍体相合与全相合异基因外周血造血干细胞移植后急性移植物抗宿主病的发生特点,探讨降低急性移植物抗宿主病发生率的方法及单倍体造血干细胞移植应用于临床的意义。 方法：行异基因外周血造血干细胞移植的患者52例,其中HLA全相合组31例,单倍体组21例。HLA单倍体组采用改良马利兰/环磷酰胺+兔抗人胸腺T细胞免疫球蛋白预处理方案,HLA全相合组采用改良马利兰/环磷酰胺预处理方案。移植物抗宿主病的预防采用短程甲氨蝶呤+环孢素A+吗替麦考酚酯的方案。 结果与结论：52例患者均获得完全持久干细胞植入。其中,急性移植物抗宿主病发病率为48%(25/52),Ⅲ-Ⅳ度急性移植物抗宿主病发病率为23%(12/52);全相合组及单倍体组急性移植物抗宿主病累积发病率分别为39%(12/31)和62%(13/21)(P > 0.05);全相合组及单倍体组Ⅲ-Ⅳ度急性移植物抗宿主病累积发病率分别为10%(3/31)和43%(9/21)(P < 0.05);发生于移植后+30 d、+31 d-+60 d、+61 d-+100 d的急性移植物抗宿主病类型分布差异无显著性意义(P > 0.05);发生在移植后+30 d内的急性移植物抗宿主病发生率高于移植后   +31 d-+60 d和+61 d-+100 d;发生急性移植物抗宿主病组和无急性移植物抗宿主病组复发率、2年无病生存率差异无显著性意义(P > 0.05),全相合组与单倍体组相比复发率差异无显著性意义(P > 0.05),2年无病生存率前者高于后者(P < 0.05)。说明采用上述移植方案,单倍体组安全性与疗效接近全相合组;在缺乏HLA相合供者时,单倍体造血干细胞移植是治疗恶性血液病的重要方法。中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程全文链接：     

单倍体相合异基因造血干细胞移植治疗白血病

背景：对于无HLA全相合同胞供者的患者,采用单倍体相合造血干细胞移植面临移植物抗宿主病重、移植相关死亡率高的风险,但通过不同的移植模式,将有可能获取相近的疗效。 目的：观察亲缘HLA单倍体相合异基因造血干细胞移植治疗白血病的疗效,并与亲缘HLA全相合异基因造血干细胞移植相比较。 方法：45例白血病患者分为2组。单倍体组移植方式为外周血或联合骨髓干细胞移植,预处理方案为改良白消安与环磷酰胺或加抗胸腺细胞球蛋白,移植物抗宿主病的预防采用环孢素A+甲氨蝶呤+霉酚酸脂;全相合组移植方式为外周血干细胞移植,预处理方案为BuCY,移植物抗宿主病的预防采用环孢素A+甲氨蝶呤。 结果与结论：两组均获得造血重建时间差异无显著性意义。单倍体及全相合组急性移植物抗宿主病的累积发病率分别为73%对52%(P > 0.05);慢性移植物抗宿主病的累积发病率分别为56%对45%(P > 0.05);移植相关死亡率分别为36%对17%(P > 0.05);单倍体组无复发,全相合组复发2例;两组的预计3年累积无病生存率分别为61%对60%(P > 0.05)。结果提示,亲缘单倍体异基因造血干细胞移植的总体疗效与亲缘全相合异基因造血干细胞移植相似,但中重度急性移植物抗宿主病的发生率较后者为高。     

异基因造血干细胞移植治疗24例重型再生障碍性贫血北大核心

背景:重型再生障碍性贫血病情重、病死率高,需快速恢复造血功能,目前异基因造血干细胞移植为一线治疗方案,同胞全相合异基因造血干细胞移植为首选,单倍体相合造血干细胞移植作为替代治疗方案也取得了较好的效果。目的:探讨异基因造血干细胞移植(包括同胞全相合造血干细胞移植及单倍体相合造血干细胞移植)治疗重型再生障碍性贫血的临床疗效。方法:回顾性分析2015年4月至2021年7月于徐州市中心医院接受异基因造血干细胞移植治疗24例重型再生障碍性贫血患者的临床资料,其中接受同胞全相合造血干细胞移植8例,接受单倍体相合造血干细胞移植16例。24例重型再生障碍性贫血患者预处理方案为氟达拉滨、环磷酰胺、抗淋巴细胞球蛋白方案。同胞全相合造血干细胞移植采用环孢素联合短程甲氨蝶呤预防移植物抗宿主病,单倍体相合造血干细胞移植在此基础上增加吗替麦考酚酯。结果与结论:①24例重型再生障碍性贫血患者中有2例患者预处理期间死于严重感染,其余22例均达造血重建;中性粒细胞植入中位时间为12.5(10-18)d,血小板植入中位时间为14.5(10-26)d;②22例植入成功患者发生急性移植物抗宿主病8例(36%),Ⅲ/Ⅳ度急性移植物抗宿主病2例,慢性移植物抗宿主病累计发生4例(18%),Ⅲ/Ⅳ度慢性移植物抗宿主病1例;③18例患者存活,6例患者死亡,5年预计总生存率为74%;④结果表明,异基因造血干细胞移植为重型再生障碍性贫血的有效治疗手段,同胞全合供者作为首选,无同胞全相合供者时可选择单倍体相合供者作为替代。     

父母供子女单倍型造血干细胞移植治疗恶性血液病

背景：单倍型造血干细胞移植是治疗恶性血液病的一种有效方法,合适的供者及快速查找到合适的供者有助于提高移植的成功率。 目的：比较父母供子女单倍型造血干细胞移植治疗恶性血液病的临床疗效。 方法：对郑州大学第一附属医院92例恶性血液病患者行父母为供者的单倍型造血干细胞移植治疗,分为父供子移植、父供女移植、母供子移植、母供女移植4组,对比4组患者移植物抗宿主病的发生率、复发率、2年无病生存率及总生存率等。 结果与结论：92例患者均完全植入并获得造血重建,4组急性移植物抗宿主病发生率、慢性移植物抗宿主病发生率和复发率差异无显著性意义(P > 0.05)。但4组Ⅲ、Ⅳ度急性移植物抗宿主病发生率、2年无病生存率、2年总生存率差异有显著性意义(P < 0.05)。其中父供子移植组、母供女移植组的Ⅲ、Ⅳ度急性移植物抗宿主病发生率低于父供女移植组和母供子移植组;同时父供子移植组和母供女移植组的2年无病生存率、2年总生存率高于父供女移植组和母供子移植组。可见父母供子女单倍型造血干细胞移植是安全可行的,供受者性别相同比供受者性别不同的疗效好。     

减低剂量预处理方案在亲缘HLA单倍体相合造血干细胞移植中的应用

背景：近年来减低剂量预处理异基因造血干细胞移植已被证明是安全有效的治疗手段,在同胞全相合和无关供者中应用逐年增多,它特别适合老年人或年轻人合并器官功能障碍的患者,然而由于找到HLA配型相合供体的概率不高,使得同胞全相合和无关供者减低剂量预处理异基因造血干细胞移植开展受限,而HLA不相合/单倍体供体则可以迅速找到,但减低剂量预处理的单倍体造血干细胞移植应用的报道还较少,国内尚未见报道,因此对减低剂量预处理的单倍体造血干细胞移植的开展情况进行综述非常重要。 目的：综述减低剂量预处理在亲缘HLA单倍体造血干细胞移植中的应用现状。 方法：以“减低剂量预处理方案、非清髓性预处理方案、HLA单倍体相合、造血干细胞移植和No-nmyeloablative  conditioning,Reduced-intensity conditioning,HLA-haploidentical,Hematopoietic stem cell transplantation”为检索词,应用计算机检索1997至2014年万方数据库、CNKI和PubMed数据库、外文医学信息资源检索平台检索关于减低剂量预处理在亲缘HLA单倍体造血干细胞移植中应用的相关文献,根据纳入标准和排除标准,最终选取25篇文献进行分析,全部为英文。 结果与结论：减低剂量预处理异基因造血干细胞移植在HLA同胞全相合及无关供者中开展的较多且效果愈来愈好。减低剂量预处理的单倍体造血干细胞移植开展的较晚且报道较少,其植入、感染、移植相关死亡、移植物抗宿主病、长期无病生存率和总生存率等各个研究的结果差异较大,早期结果稍差,而近期总体情况有明显改善。目前看减低剂量预处理的单倍体造血干细胞移植是可行的,尤其对于找不到同胞相合及无关全相合供者的患者来说,HLA单倍体相合的血缘关系亲属成为最有潜力的干细胞来源。减低剂量预处理的单倍体造血干细胞移植保留较强的移植物抗白血病效应,且寻找供者容易,有足够的细胞后续治疗如供者淋巴细胞输注,同时通过发挥移植物抗白血病效应,可有效清除患者体内的肿瘤细胞,为处在疾病进展期或经历多次治疗失败的患者,尤其是老年患者、合并器官功能障碍及并发症患者,提供有效的挽救治疗手段。但由于开展的时间较短,今后在应用中该如何选择最佳方案、最佳时机以及减低移植物抗宿主病、移植相关死亡率及复发率等尚需进一步深入的研究。中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程全文链接：     

父母供者外周血单倍体干细胞移植治疗儿童复发难治急性白血病

背景:儿童复发难治急性白血病单纯化学治疗效果极差,异基因造血干细胞移植是治愈该类疾病的惟一有效方法。研究显示单倍体移植与同胞相合及非亲缘全相合造血干细胞移植的治疗效果接近,甚至优于后者,且父母作为供者单倍体造血干细胞移植依从性好,能够保证移植干细胞数量及预防原发病复发,明显提高了患者移植成功率及长期无白血病生存率。目的:回顾分析父母供者单倍体外周血造血干细胞移植治疗儿童复发难治急性白血病的疗效。方法:入选35例父母供者外周血单倍体造血干细胞移植治疗儿童复发难治急性白血病。均采用"改良1,4-丁二醇二甲磺酸酯/环磷酰胺+胸腺细胞免疫球蛋白"预处理方案和环孢素、吗替麦考酚酯及甲氨蝶呤三联短程预防移植物抗宿主病。结果与结论:35例父母供者外周血单倍体造血干细胞移植治疗儿童复发难治急性白血病均植入成功。135例患儿回输单个核细胞中位数为5.82(3.23-8.45)×108/kg,其中CD34+细胞中位数为4.52(2.37-11.51)×106/kg。2干细胞回输后100 d内,移植相关死亡率为14.3%。33-Ⅱ度急性移植物抗宿主病发生率为34.3%,Ⅲ-Ⅳ度急性移植物抗宿主病发生率为37.1%,慢性移植物抗宿主病总发生率为42.9%。42年无白血病生存率为42.9%,2年总生存率为51.4%,2年原发病复发率为34.3%,中位生存时间为24个月。提示对于无人类白细胞抗原相合同胞供者及不能及时寻找到非血缘人类白细胞抗原相合供者的儿童复发难治急性白血病,父母供者外周血单倍体造血干细胞移植是一种高效可行的治疗方法。     

干细胞移植治疗重型再生障碍性贫血：研究应用与进展

文题释义：获得性再生障碍性贫血：是一种免疫介导的骨髓衰竭性疾病,主要表现为骨髓有核细胞增生低下、一系或多系血细胞减少及其所致的贫血、出血和感染。获得性再生障碍性贫血的发病机制尚未完全阐明,目前认为T淋巴细胞异常活化、功能亢进造成骨髓造血功能衰竭在获得性再生障碍性贫血发病机制中占主要地位。 人类白细胞抗原：即HLA,是人类主要组织相容性复合体的表达产物,HLA的研究最初是在器官移植研究推动下开展起来的,因此HLA又称移植抗原。在遗传学中,主要组织相容性复合体是作为一个单位孟德尔式传递的。因此,同胞之间可有HLA相同、半相同和不同3种情况。 背景：异基因造血干细胞移植仍然是获得性重型再生障碍性贫血患者的唯一治愈方法,如何选择适合移植的重型再生障碍性贫血患者进行治疗成为近年的研究热点。 目的：从HLA全相合无关供者造血干细胞移植、非血缘脐血移植和单倍体相合造血干细胞移植3个方面进行综述,阐述异基因造血干细胞移植的研究进展。 方法：检索2000至2018年期间收录在PubMed、中国知网期刊全文数据库及万方数据库中异基因造血干细胞移植治疗重型再生障碍性贫血的相关文献,检索词为“unrelated donor,haploidentical,unrelated cord blood,severe aplastic anemia”及“无关供者,单倍体相合,无血缘脐血,重型再生障碍性贫血”。 结果与结论：①HLA全相合同胞供者造血干细胞移植是治疗重型再生障碍性贫血的一线治疗方案,但鉴于HLA相合同胞供者不易寻找,HLA全相合无关供者造血干细胞移植作为重要的替代治疗手段,目前疗效已接近HLA全相合同胞供者造血干细胞移植,但移植物抗宿主病、严重感染的发生率仍高于HLA全相合同胞供者造血干细胞移植,在选择HLA全相合无关供者造血干细胞移植治疗时仍然需要多因素综合考虑;②脐血造血干细胞来源丰富且配型成功率高,使得非血缘脐血移植的应用变得普遍,预冻存总有核细胞量>3.9×10⁷/kg时非血缘脐血植入概率较高,但鉴于非血缘脐血植入延迟、免疫功能重建延迟等因素,临床治疗重型再生障碍性贫血时只有在其他移植方式不可行且第1个疗程免疫抑制治疗失败后才应考虑非血缘脐血移植;③单倍体相合造血干细胞移植具有供者易获得且依从性好等优点,疗效接近全相合移植,现已成为一种重要的替代移植选择;巴利昔单抗和(或)抗胸腺细胞球蛋白的使用有望降低移植物抗宿主病的发生率以拓展单倍体相合造血干细胞移植的临床应用范围。 ORCID: 0000-0003-3509-920X(丁宇斌) 中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程     

单倍体相合造血干细胞移植治疗高危白血病

背景：异基因造血干细胞移植是治疗高危白血病的主要方法,单倍体相合的造血干细胞移植扩展了移植的应用范围。 目的：观察“改良Bu/Cy+ATG”为预处理方案的单倍体相合造血干细胞移植治疗高危白血病的疗效。 方法：对19例高危白血病患者,均采用“改良Bu/Cy+ATG”预处理方案,采用外周血造血干细胞移植5例,外周血+骨髓造血干细胞移植14例。应用甲氨蝶呤,环孢素A,吗替麦考酚酯预防移植物抗宿主病。 结果与结论：①短期疗效：中性粒细胞恢复的中位时间为12(8~20) d;血小板恢复的中位时间为13(10~31) d;移植后100 d内,移植相关死亡率为(15.8±8.4)%。②移植物抗宿主病发生情况：Ⅰ~Ⅳ度急性移植物抗宿主病总发生率(63.1±11.1)%,慢性移植物抗宿主病发生率(54.54±15.0)%。③远期疗效：2年无病生存率为(28.2±15.5)%,2年总体生存率为(46.9±16.5)%。结果提示,高危白血病无人类白细胞抗原相合血缘供者及无人类白细胞抗原相合非血缘供者,而又急需进行挽救性移植时,“改良Bu/Cy+ATG”为预处理方案的单倍体相合造血干细胞移植是一种可行的选择。     

ABO血型不合外周血造血干细胞移植10例

背景：ABO血型不合供受者之间进行外周血造血干细胞移植,面临受者血型的转变、移植后输血的选择等问题。 目的：观察ABO血型不合外周血造血干细胞移植治疗血液病的临床疗效和近远期并发症。 方法：回顾性分析了2005/2008武警总医院收治的10例ABO血型不合异基因外周血同胞供者造血干细胞移植患者的资料。总结植入效果,血型转变,移植物抗宿主病以及不良反应。 结果与结论：9例患者恢复造血功能,血型转变为完全供者型,1例患者白细胞血小板恢复,但红细胞植入延迟。所有患者在输注移植物时未出现短暂的血红蛋白尿,无严重急性溶血和迟发型溶血的发生,1例出现严重的移植物抗宿主病。可见ABO血型不合外周血造血干细胞移植对移植疗效无明显影响,红细胞植入延迟的预防和处理十分重要。     

异基因外周血造血干细胞移植治疗白血病*

背景：异基因外周血造血干细胞移植是治疗白血病的有效手段。 目的：比较血缘与非血缘供者异基因外周血造血干细胞移植治疗白血病的造血重建、免疫重建、感染、移植物抗宿主病及疗效。 方法：选择接受异基因外周血造血干细胞移植治疗的白血病患者45例,其中30例患者接受血缘供者造血干细胞移植(血缘组),15例患者接受非血缘供者造血干细胞移植(非血缘组)。 结果与结论：①造血重建：血缘组白细胞和血小板重建时间均快于非血缘组(P < 0.05)。在移植后30~40 d植活证据指标测定提示异体造血干细胞在受者体内完全植活。②T细胞重建：两组移植后各时间点T细胞重建差异无显著性意义。③感染发生率：两组移植后早期感染发生率,急、慢性移植物抗宿主病发生率差异无显著性意义(P > 0.05)。④白血病复发：两组移植后复发率差异无显著性意义(P > 0.05)。⑤无病生存：两组移植后2年无病生存率差异无显著性意义(P > 0.05)。表明血缘供者异基因外周血造血干细胞移植后的造血重建较非血缘供者迅速,但两者间移植后T细胞重建、感染发生率、移植物抗宿主病及无病生存并无差异。      

Role of Antithymocyte Globulin and Granulocyte-Colony Stimulating Factor-Mobilized Bone Marrow in Allogeneic Transplantation for Patients with Hematologic Malignancies

The main obstacle for allogeneic transplantation is delayed hematologic reconstitution and serious graft-versus-host disease (GVHD). The results of 128 patients with hematologic malignancies undergoing HLA-identical (n = 52) or HLA-haploidentical/mismatched (n = 76) hematopoietic stem cell transplantation (HSCT) performed during the same time period were compared. Patients with HLA-identical HSCT received unmanipulated granulocyte-colony stimulating factor-mobilized peripheral blood stem cells (G-PBSCs). Forty-six patients with HLA-haploidentical related HSCT received antithymocyte globulin (ATG) in conditioning regimens followed by the transplantation of the combination of unmanipulated G-PBSCs and granulocyte-colony stimulating factor-mobilized bone marrow (G-BM) and 30 patients with HLA-mismatched unrelated HSCT received ATG in conditioning regimens followed by the transplantation of unmanipulated G-PBSCs. All patients got successful hematopoietic engraftment. The cumulative incidences of grades I to II acute GVHD (aGVHD) on day 100 in the identical, haploidentical related and mismatched unrelated cohorts were 21.2%, 43.5%, and 53.3%, respectively. The cumulative incidences of chronic GVHD (cGVHD) in the identical, mismatched unrelated, and haploidentical related cohorts were 34.6%, 33.3%, and 10.9%, respectively. The 2-year relapse and treatment-related mortality (TRM) rates were 19.2%, 23.9%, 23.3%, and 9.6%, 8.7%, 10% for patients who underwent identical, HLA-haploidentical related, and mismatched unrelated transplantation, respectively. The 2-year probabilities of leukemia-free survival and overall survival were 72.2%, 70.6%, 68.1%, and 76.5%, 77.8%, 70.0% after identical, haploidentical related and mismatched unrelated transplantations, respectively. Multivariate analyses showed that only advanced disease stage and a diagnosis of disease had increased risk of relapse, treatment failure, and overall mortality. In conclusion, it is a feasible approach with acceptable outcomes for patients undergoing HLA-haploidentical related HSCT by the combination of G-PBSCs and G-BM with conditioning regimens including ATG.     

Haploidentical Transplantation with Post-Transplant Cyclophosphamide versus Unrelated Donor Hematopoietic Stem Cell Transplantation: A Systematic Review and Meta-Analysis

Hematopoietic stem cell transplantation (HSCT) is the standard treatment for patients with high-risk hematologic malignancies. Only approximately 25% of siblings are HLA-matched, and thus alternative donors—unrelated or haploidentical—are usually the only options available. This meta-analysis aimed to compare haploidentical HSCT with post-transplantation cyclophosphamide and unrelated donor (URD) HSCT. We searched the PubMed and Cochrane databases for pertinent studies indexed between 2008 and 2018. Twenty observational studies (with a total of 1783 haploidentical HSCT recipients and 6077 URD HSCT recipients) were included. Results for overall survival, graft-versus-host disease (GVHD), nonrelapse mortality (NRM), and relapse incidence were pooled. Measures of association used were hazard ratios and risk differences. The median age was 51 years for haploidentical transplant recipients and 52 years for URD transplant recipients. Peripheral blood stem cell (PBSC) grafts were more frequent in the URD transplant recipients (85%) than in the haploidentical transplant recipients (31%). Overall survival was not different between the 2 groups. NRM was lower for haploidentical transplantation. All forms of GVHD (acute grades II-IV and III-IV and moderate, severe, and extensive chronic) were lower with haploidentical donor HSCT. The risk of chronic GVHD was fairly proportional to the differential use of PBSC grafts across studies, however. All included studies were retrospective, representing the major limitation of this meta-analysis. In conclusion, haploidentical HSCT for hematologic malignancies achieved the same overall survival as URD HSCT, with a lower incidence of GVHD and NRM. The increased frequency of PBSC use in the unrelated donor group could partially explain the higher cGVHD rate. Haploidentical transplantation with post-transplantation cyclophosphamide should strongly be considered as the first option for adult patients with hematologic malignancies who do not have matched sibling donors in experienced centers. This systematic review has been registered at PROSPERO (65790).     

The transplantation of hematopoietic stem cells after non-myeloablative conditioning: a cellular therapeutic approach to hematologic and genetic diseases

Originally, allogeneic hematopoietic stem cell transplantation (HSCT) was viewed as a form of rescue from the marrow lethal effects of high doses of chemo-radiotherapy used to both eradicate malignancy and to provide sufficient immunosuppression to ensure allogeneic engraftment. Clear evience of a therapeutic graft-versus-tumor (GVT) effect mediated by allogeneic affector cells (T cells) has prompted the exploration of HSCT regimens that rely solely upon host immunosuppression (non-myeloblative) to facilitate allogenic donor engraftment. The engrafted donor effector cells are then used to accomplish the task of eradicating host malignant cells. The non-myeloblative regimen developed in Seattle uses 2 Gy total body irradiation (TBI) before transplant followed by postgrafting cyclosporine (CSP) and mycophenolate mofetil (MMF). This regimen resulted in initial mixed donor-host chimerism in all patients with hematologic malignancies and genetic disorders who received HLA-matched sibling allografts. The 17% incidence of graft rejection was reduced to 3% with the addition of fludarabine, 30 mg/m²/day on d-4,-3, and-2. The non-myeloblative combination of fludarabine/TBI has also been successful at achieving high engraftment rates in recipients of 10 of 10 HLA antigen matched unrelated donor HSCTs in patients with hematologic malignancies. By reducing acute toxicities relative to conventional HSCT, most patients have received their pre- and post-HSCT therapy almost exclusively as outpatients. Acute and chronic GVHD occur after non-myeloablative HSCT, but the incidence and severity appear less compared to conventional HSCT. As in conventional transplants, immune dysregulation from GVHD and its treatment and delayed reconstitution of immune function continue to present risks to patients who have otherwise undergone successful non-myeloablative HSCT. Cellular therapeutic effects have been nobserved after non-myeloblative HSCT such as correction of inherited genetic disorders, and eradication of hematologic malignant diseases and renal cell carcinoma via GVT responses.     

Mismatched Related and Unrelated Donors for Allogeneic Hematopoietic Cell Transplantation for Adults with Hematologic Malignancies

Two parallel phase II trials in adults with hematologic malignancies demonstrated comparable survival after reduced-intensity conditioning and transplantation of either 2 HLA-mismatched umbilical cord blood (UCB) units or bone marrow from HLA-haploidentical relatives. Donor choice is often subject to physician practice and institutional preference. Despite clear preliminary evidence of equipoise between HLA-haploidentical related donor and double unrelated donor UCB transplantation, the actual prospect of being randomized between these 2 very different donor sources is daunting to patients and their treating physicians alike. Under these circumstances, it is challenging to conduct a phase III randomized trial in which patients are assigned to the UCB or haploidentical bone marrow arms. Therefore, we aimed to provide an evidence-based review and recommendations for selecting donors for adults without an HLA-matched sibling or an HLA-matched adult unrelated donor.     

Incidence of invasive fungal disease after unmanipulated haploidentical stem cell transplantation was significantly higher than that after HLA-matched sibling transplantation

The aim of this study was to determine the incidence, clinical features and outcome of invasive fungal disease (IFD) after either unmanipulated haploidentical haematopoietic stem cell transplantation (HSCT) or human leukocyte antigen (HLA)-matched sibling HSCT. This was a head-to-head comparative study performed at a single centre. Patients were admitted between 2007 and 2010, and IFD was evaluated according to the revised EORTC/MSG criteria, with only proven and probable cases included. Of the 1042 consecutive patients enrolled, 390 received the HLA-matched HSCT and 652 received unmanipulated haploidentical HSCT. A total of 61 (5.8%) patients had IFD, including 15 proven cases and 46 probable cases. The incidence of IFD after unmanipulated haploidentical HSCT was significantly higher than that after HLA-matched transplantation (7.1% vs. 3.3%, respectively; p 0.007). IFD occurred later in patients receiving HLA-matched transplantation compared with patients receiving unmanipulated haploidentical HSCT (141.5 vs. 23 days, respectively; p 0.04). In multivariate analysis, acute graft-versus-host disease (GVHD) grades III to IV (HR = 2.214, 95% CI, 1.139–4.304; p 0.019), extensive chronic GVHD (HR = 2.413, 95% CI, 1.377–4.228; p 0.002) and haploidentical transplantation (HR = 2.648, 95% CI, 1.111–6.310; p 0.028) were identified as significant risk factors associated with IFD. The response to antifungal therapy and the IFD-attributable mortality were similar between the two types of transplantation. In conclusion, patients who received unmanipulated haploidentical HSCT had a higher risk of IFD than those patients who received HLA-matched HSCT, but the prognosis of IFD was not associated with the HLA type.     

Current Use of Total Body Irradiation in Haploidentical Allogeneic Hematopoietic Stem Cell Transplantation

Total body irradiation (TBI) is included in the conditioning regimen for allogeneic hematopoietic stem cell transplantation (HSCT), with unique advantages such as uniform distribution over the whole body and decreased exposure to cytotoxic chemotherapeutic agents. For individuals who lack matched sibling or matched unrelated donors, the use of haploidentical donors has been increasing despite challenges such as graft rejection and graft-versus-host disease (GVHD). Although a limited number of studies have been performed to assess the clinical role of TBI in haploidentical HSCT, TBI-based conditioning showed comparable results in terms of survival outcomes, rate of relapse, and GVHD in diverse hematologic malignancies such as leukemia, lymphoma, and multiple myeloma. Advances in supportive care, along with recent technical improvements such as restriction of maximum tolerated dose, appropriate fractionation, and organ shielding, help to overcome diverse adverse events related to TBI. Post-transplantation cyclophosphamide was used in most studies to reduce the risk of GVHD. Additionally, it was found that post-transplantation rituximab may improve outcomes in TBI-based haploidentical HSCT, especially in patients with B-cell lymphoma. Along with the advances of techniques and strategies, the expansion of age restriction would be another important issue for TBI-based haploidentical HSCT considering the current tendency toward increasing age limitation and lack of matched donors. This review article summarizes the current use and future perspectives of TBI in haploidentical HSCT.     

Long-Term Outcome and Evaluation of Organ Function in Pediatric Patients Undergoing Haploidentical and Matched Related Hematopoietic Cell Transplantation for Sickle Cell Disease

HLA-matched related donor (MRD) hematopoietic stem cell transplantation (HSCT) is a well-established therapy for patients with sickle cell disease (SCD); however, experience using alternative donors, including haploidentical donors, in HSCT for SCD is limited. We report the long-term outcomes of 22 pediatric patients who underwent related donor HSCT for SCD at St. Jude Children's Research Hospital, either a myeloablative sibling MRD HSCT (n = 14) or reduced-intensity parental haploidentical donor HSCT (n = 8). The median patient age was 11.0 ± 3.9 years in the MRD graft recipients and 9.0 ± 5.0 years in the haploidentical donor graft recipients. The median follow-up was 9.0 ± 2.3 years, with an overall survival (OS) of 93% and a recurrence/graft failure rate of 0%, for the MRD cohort and 7.4 ± 2.4 years, with an OS of 75%, disease-free survival of 38%, and disease recurrence of 38%, for the haploidentical donor cohort. We report the long-term hematologic response and organ function in patients undergoing MRD or haploidentical donor HSCT for severe SCD. Our data demonstrate long-term hematologic improvements after HSCT with sustained engraftment, and confirm that HSCT offers long-term protection from common complications of SCD, including stroke, pulmonary hypertension, acute chest, and nephropathy, regardless of donor source.     

Allogeneic hematopoietic stem cell transplant using mismatched/haploidentical donors.

Haploidentical hematopoietic stem cell transplantation (HSCT) provides an opportunity for nearly all patients to benefit from HSCT when a human leukocyte antigen (HLA) genotypically matched sibling is not available. Initial results with the use of mismatched allografts led to limited enthusiasm because of graft-versus-host disease (GVHD) and infectious complications, resulting in an unacceptable treatment-related morbidity and mortality. Recent advances with effective T cell depletion, the use of a "megadose" of stem cells, earlier detection of severe infections, combined with better antimicrobial therapy and reduced-intensity conditioning (RIC) has significantly decreased the early transplant-related mortality and GVHD, whereas enabling prompt engraftment, hence advancing the therapeutic benefit of haploidentical transplantation. However, the cardinal problems related to delayed immune reconstitution allowing posttransplant infectious complications and relapse remain, limiting the efficacy of haploidentical HSCT. Preliminary data has demonstrated the potential for use of adoptive cellular immunity and selective allodepletion in rapidly reconstituting immunity without GVHD. The encouraging reports from haploidentical transplant using noninherited maternal antigen (NIMA)-mismatched or natural killer (NK) alloreactive donors may greatly increase the donor availability and open the way to more appropriate donor selection in HLA-haploidentical HSCT. Future challenges remain in determining the safest approach for haploidentical transplant to be performed with minimal risk of GVHD, whereas preserving effective graft-versus-leukemia activity and promoting prompt immune reconstitution.     

Immune Reconstitution after Haploidentical Hematopoietic Stem Cell Transplantation

Haploidentical hematopoietic stem cell transplantation (HSCT) offers the benefits of rapid and nearly universal donor availability and has been accepted worldwide as an alternative treatment for patients with hematologic malignancies who do not have a completely HLA-matched sibling or who require urgent transplantation. Unfortunately, serious infections and leukemia relapse resulting from slow immune reconstitution remain the 2 most frequent causes of mortality in patients undergoing haploidentical HSCT, particularly in those receiving extensively T cell–depleted megadose CD34⁺ allografts. This review summarizes advances in immune recovery after haploidentical HSCT, focusing on the immune subsets likely to have the greatest impact on clinical outcomes. The progress made in accelerating immune reconstitution using different strategies after haploidentical HSCT is also discussed. It is our belief that a predictive immune subset–guided strategy to improve immune recovery might represent a future clinical direction.