造血干细胞移植与非移植治疗重型再生障碍性贫血的比较

背景：造血干细胞移植是公认的重型再生障碍性贫血最好的治疗办法。国内外已经开始进行了多种造血干细胞来源的移植,包括亲缘单倍体移植、非血缘移植,而联合间充质干细胞移植提高疗效的报道多为单独个案报道。目的：回顾性对比分析造血干细胞移植与非移植治疗重型再生障碍性贫血的疗效。方法：2008-04/2010-04住院的17例重型再生障碍性贫血患者,年龄3～53岁,8例患者接受造血干细胞移植,9例患者接受了非移植治疗。移植组的8例患者分别接受了亲缘HLA半相合（4例）、HLA相合（2例）,非血缘（2例）的造血干细胞移植,在所有移植的患者中有4例在造血干细胞输注的同时静脉输注体外培养扩增的间充质造血干细胞。非移植治疗组9例患者主要采用免疫抑制剂和促造血治疗。结果与结论：移植组除1例45岁患者接受过非移植方法治疗11个月无效,合并肾功能衰竭、肺部真菌感染时才行造血干细胞移植,死于移植合并症外,余7例患者移植后染色体及DNA指纹检测等说明造血干细胞移植完全供者植入,造血功能恢复快,中性粒细胞达到0.5×109L-1,血小板计数≥20×109L-1中位时间分别为12d和14d;其中接受间充质干细胞输注的4例患者平均中性粒细胞达到0.5×109L-1,血小板计数≥20×109L-1的中位时间均为11.6d。移植患者发生Ⅰ,Ⅱ度急性移植物抗宿主病4例,局限慢性移植物抗宿主病者4例,移植后生活质量良好,无需血制品输注,无严重感染和出血。而非移植组患者治疗后造血功能均未恢复正常,1例死于脑出血和感染,余患者生活质量低下,需要反复住院对症治疗,长期间断的血制品输注;治疗后出现多种严重的合并症。结果表明造血干细胞移植是高效的治疗重型再生障碍性贫血的方法,患者造血恢复快,移植物抗宿主病可以预防和控制,生活质量高,疗效明显优于非移植治疗。     

多种来源造血干细胞移植治疗重型再生障碍性贫血

背景：造血干细胞移植是年轻重型再生障碍性贫血患者首选方法,但在中国多数重型再生障碍性贫血患者无合适的供者,单倍体相合或非血缘造血干细胞移植国内外目前还处于探索阶段,联合间充质干细胞移植报道少见。目的：观察不同干细胞来源造血干细胞移植治疗重型再生障碍性贫血的疗效。方法：10例（3～52岁）重型再生障碍性贫血患者,分别接受了亲缘HLA相合（2例）,单倍体相合（5例）,非血缘（3例）的外周血和/或骨髓造血干细胞移植,其中5例患者同时联合了间充质干细胞共移植。预处理方案主要为环磷酰胺、氟达拉滨和抗人胸腺球蛋白,以霉酚酸酯、环孢素A加短疗程的甲氨蝶呤预防移植物抗宿主病,单倍体相合移植的患者在此基础上加马利兰和CD25单克隆抗体;同基因的例5患者预处理方案为抗人胸腺球蛋白＋甲基泼尼龙。输注间充质干细胞的量为（0.27～1.85）×106/kg。接受和未接受间充质干细胞组的患者回输的造血干细胞有核细胞分别为（7.4～17.38）×108/kg和（6.09～13.68）×108/kg。结果与结论：除1例单倍体相合患者移植未成功,＋36d死于并发症外,余患者移植后染色体及DNA指纹检测等说明造血干细胞移植完全供者植入。移植后中性粒细胞达到0.5×109L-1,血小板计数≥20×109L-1中位时间分别为12d和13d;其中造血功能恢复快慢的趋势是同基因移植〉外周血或/和骨髓＋间充质干细胞移植〉单纯外周血或/和骨髓干细胞移植,而亲缘HLA全相合的52岁患者造血恢复最慢。非血缘移植例1、6患者发生了Ⅰ度急性移植物抗宿主病,单倍体相合移植的例2和例10患者发生了Ⅱ度急性移植物抗宿主病后出现了局限性的慢性移植物抗宿主病,余下患者移植后生活质量良好,无慢性移植物抗宿主病;除未接受间充质干细胞的例3患者移植后出现严重感染外,其余患者移植后再未出现严重的感染和出血。结果提示造血干细胞是安全,高效治疗重型再生障碍性贫血的方法,联合应用间充质造血干细胞者患者造血恢复快,移植并发症少。     

多种来源造血干细胞移植治疗重型再生障碍性贫血

背景:造血干细胞移植是年轻重型再生障碍性贫血患者首选方法,但在中国多数重型再生障碍性贫血患者无合适的供者,单倍体相合或非血缘造血干细胞移植国内外目前还处于探索阶段,联合间充质干细胞移植报道少见.目的:观察不同干细胞来源造血干细胞移植治疗重型再生障碍性贫血的疗效.方法:10例(3～52岁)重型再生障碍性贫血患者,分别接受了亲缘HLA相合(2例),单倍体相合(5例),非血缘(3例)的外周血和/或骨髓造血干细胞移植,其中5例患者同时联合了间充质干细胞共移植.预处理方案主要为环磷酰胺、氟达拉滨和抗人胸腺球蛋白,以霉酚酸酯、环孢素A加短疗程的甲氨蝶呤预防移植物抗宿主病,单倍体相合移植的患者在此基础上加马利兰和CD25单克隆抗体;同基因的例5患者预处理方案为抗人胸腺球蛋白+甲基泼尼龙.输注间充质干细胞的量为(0.27～1.85)×106/kg.接受和未接受间充质干细胞组的患者回输的造血干细胞有核细胞分别为(7.4～17.38)×108/kg和(6.09～13.68)×108/kg.结果与结论:除1例单倍体相合患者移植未成功,+36 d死于并发症外,余患者移植后染色体及DNA指纹检测等说明造血干细胞移植完全供者植入.移植后中性粒细胞达到0.5×109 L-1,血小板计数≥20×109 L-1中位时间分别为12 d和13 d;其中造血功能恢复快慢的趋势是同基因移植>外周血或/和骨髓+间充质干细胞移植>单纯外周血或/和骨髓干细胞移植,而亲缘HLA全相合的52岁患者造血恢复最慢.非血缘移植例1、6患者发生了Ⅰ度急性移植物抗宿主病,单倍体相合移植的例2和例10患者发生了Ⅱ度急性移植物抗宿主病后出现了局限性的慢性移植物抗宿主病,余下患者移植后生活质量良好,无慢性移植物抗宿主病;除未接受间充质干细胞的例3患者移植后出现严重感染外,其余患者移植后再未出现严重的感染和出血.结果提示造血干细胞是安全,高效治疗重型再生障碍性贫血的方法,联合应用间充质造血干细胞者患者造血恢复快,移植并发症少.     

异基因造血干细胞移植治疗重型再生障碍性贫血

背景:近年来随着造血干细胞移植技术的提高和免疫抑制剂的使用,重型再生障碍性贫血的治疗效果有了明显改善,尤其是亲缘间HLA配型全相合异基因造血干细胞移植,取得了较高的治愈率。目的:观察异基因造血干细胞移植治疗重型再生障碍性贫血的疗效。方法:自2009至2011年采用异基因造血干细胞移植治疗重型再生障碍性贫血患者20例,HLA配型全相合12例,不全相合8例。移植预处理采用氟达拉滨+兔抗人胸腺细胞免疫球蛋白+环磷酰胺。除1例为非血缘外周血干细胞移植外,其他患者干细胞来源为动员后的骨髓和外周血干细胞联合移植。HLA全相合移植物抗宿主病预防采用环孢素联合短程甲氨蝶呤,不全相合患者采用环孢素、短程甲氨蝶呤联合吗替麦考酚酸酯。结果与结论:移植后中性粒细胞恢复>0.5×109L-1平均为12.5 d,血小板恢复>20×109 L-1平均为+18 d。20例患者随访24-60个月,总生存率75%(15例),治愈率70%(14例),死亡5例;12例全相合患者中83%治愈(10例),8例不全相合患者治疗有效率62%(5例),治愈率50%(4例)。20例患者中发生急性及慢性移植物抗宿主病5例,治疗中并发败血症4例,侵袭性真菌感染3例。结果可见异基因干细胞移植是治疗重型再生障碍性贫血的有效方法之一,尤以HLA全相合效果良好,移植后恢复快,移植物抗宿主病发生率低。     

单倍体相合造血干细胞移植治疗儿童重型再生障碍性贫血

背景：目前治疗儿童再生障碍性贫血的主要方法为强化免疫抑制治疗或干细胞移植,后者由于供者来源少而受到限制,HLA单倍体相合的异基因造血干细胞在白血病治疗中常见应用,在再生障碍性贫血治疗中较少应用。目的：探讨单倍体相合的造血干细胞移植联合胎盘来源的间充质干细胞移植治疗重型儿童再生障碍性贫血的疗效。方法：患儿,女,7岁,确诊重型再生障碍性贫血1年半,2012-07-09接受HLA单倍体相合的异基因骨髓及外周血单个核细胞联合胎盘来源间充质干细胞移植,供者为母亲。预处理采用氟达拉滨联合环磷酰胺和抗胸腺细胞球蛋白方案。结果与结论：移植后＋9 d中性粒细胞〉0.5×109 L-1,＋12 d完成造血重建,＋100 d查STR提示植入完成。移植后＋8个月停用免疫抑制药物,未发生急、慢性移植物抗宿主病。患儿随访18个月,无病生存。结果表明,HLA单倍体相合的造血干细胞联合胎盘来源间充质细胞移植治疗儿童重型再生障碍性贫血是一种安全有效、值得探索的方法。     

单倍体相合造血干细胞联合脐带血间充质干细胞移植治疗急性重型再生障碍性贫血的疗效观察

本研究探讨单倍体相合造血干细胞移植联合脐带血间充质干细胞治疗重型再生障碍性贫血(SAA)的方法和疗效。对5例SAA的患者进行了单倍体相合造血干细胞移植。移植物选择单倍体相合供者骨髓或外周造血干细胞加脐带血间充质干细胞。观察移植后临床造血重建时间及近期并发症。结果显示,所有SAA患者移植后均获得造血重建,白细胞计数大于2×109/L的平均时间是13.8天,血小板计数大于20×109/L的平均时间是17.8天,第30天行患者外周血STR-PCR检测显示为完全供者的基因型。除1例发生癫痫失去联系外,其余4例均无病存活至今,仍在继续随访中。总之,单倍体相合造血干细胞联合脐带血间充质干细胞移植是治疗急性SAA有效可行的方法,但还须大样本的研究。     

减低剂量的脐血造血干细胞移植/输注治疗重型再生障碍性贫血21例临床研究

目的观察HLA基因位点不相合的非亲缘脐血造血干细胞移植（简称脐血移植）治疗重型再生障碍性贫血（SAA）的疗效。方法采用3~6个HLA基因位点相合的非亲缘脐血移植/输注治疗重型SAA患者21例。从血缘关系及HLA基因位点、SAA分型、患者体重4个方面进行研究。预处理方案：环磷酰胺50mg·kg^-1·d^-1×2d＋抗人淋巴细胞球蛋白15mg·kg^-1·d^-1/抗胸腺细胞球蛋白3mg·kg^-1·d^-1×5d。应用环孢素A预防移植物抗宿主病（GVHD）。结果5组患者均能达到造血快速重建,总的完全造血重建率达80.98%。根据SAA分型,21例患者中SAA-Ⅰ型16例,15例达到完全造血重建,1例死亡。SAA-Ⅱ型5例,2例完全造血重建,2例部分重建,1例死亡。体重〈60kg的SAA患者13例,11例完全造血重建,2例部分造血重建。体重大于60kg的SAA患者8例,6例完全造血重建,2例死亡。结论脐血移植/输注治疗SAA是一种有效的治疗方法,特别适合于SAA-Ⅰ型的低体重儿童,其配型要求无需十分严格,大体重儿童或成年人应用双份脐血同样可以达到很好的治疗效果。     

第二次单倍体造血干细胞移植治疗首次移植失败再生障碍性贫血并发淋巴瘤1例

背景：急性重型再生障碍性贫血第一次异基因造血干细胞移植失败对患儿是严重致命的,若同时合并有继发性淋巴瘤等多种并发症,治疗就更为棘手,目前无成功方法可借鉴。目的：探讨第二次HLA单倍体造血干细胞移植治疗首次移植失败且并发淋巴瘤的急性重型再生障碍性贫血患儿的有效性和安全性。方法：回顾性分析1例急性重型再障患儿的二次造血干细胞移植的临床资料：患儿男,3岁,2011年11月25日行第一次非血缘异基因外周血干细胞移植（供受者HLA为8/10相合,血型主要不合）,移植后粒细胞和血小板造血分别在11 d和14 d恢复,移植后30 d DNA移植植入鉴定和染色体检测均示移植成功植入,术后35 d出现皮肤Ⅰ度移植物抗宿主病,激素治疗后消失,术后54 d因出现自身免疫性溶血性贫血及纯红细胞再生障碍性贫血,给予大剂量丙种球蛋白冲击、激素及促红素等治疗好转,激素逐渐减量,EBV拷贝数逐渐升高,术后3个月患者出现发热、双侧颈部可触及数个肿大淋巴结,行B超引导下右侧颈部淋巴结穿刺活检,考虑移植后淋巴增殖性疾病,病理示：弥漫大B细胞淋巴瘤,治疗上减停免疫抑制剂,应用美罗华及CHOP方案化疗,淋巴结缩小,且EBV拷贝数下降,体温正常。移植术后5个月复查血象和骨髓象提示继发性植入失败,进而于2012年5月15日行第二次单倍体相合造血干细胞移植。供者为患儿的父亲,预处理方案为清髓性预处理方案：氟达拉滨＋环磷酰胺＋马利兰＋米托蒽醌＋抗CD52单克隆抗体。回输骨髓造血干细胞的同时输注脐带间充质干细胞。移植物抗宿主病预防：环孢素A＋短程的甲氨喋呤＋CD25单克隆抗体联合霉酚酸酯。回输的有核细胞分别为13.52×108/kg,CD34＋细胞数为2.45×106/kg,无关供者脐带来源间充质干细胞的量为1×106/kg。随访时间为移植后24个月。结果与结论：移植后中?     

脂肪源性间充质干细胞联合造血干细胞共移植治疗顽固性重型再生障碍性贫血2例

选取2002-08/2007-1 2在河南省血液病研究所收治的2例顽固性重型再生障碍性贫血患儿,脂肪源性间充质干细胞分别来源于HLA半相合患儿母亲,外周血造血干细胞来源于HLA全相合的患儿同胞哥哥或妹妹.患儿1接受外周血造血干细胞与脂肪源性间充质干细胞(1×106/kg)恶共移植,输注的单个核细胞数4.5×108/kg,其中CD34+细胞和CD3+细胞分别为4.41×106/kg及0.11×105/kg;患儿2接受外周血造血干细胞与半相合脂肪源性间充质干细胞(1×106/kg)共移植,输注的单个核细胞数6.5×108/kg,其中CD34+细胞和CD3+细胞分别为4.62×106/kg及0.12×105/kg.结果两例患儿均移植成功,随访2年来患儿状态良好、未给予其他任何治疗,无输血依赖性.     

非血缘HLA相合供者造血干细胞移植治疗重型再生障碍性贫血的临床分析

本研究旨在评价HLA不全相合的亲属供者或HLA相合非血缘供者造血干细胞移植在治疗重型再生障碍性贫血(SAA)的疗效和安全性。在2005年11月至2011年5月期间采用非血缘供者或者单倍体相合供者造血干细胞移植治疗SAA患者20例,其中亲缘HLA不合单倍体相合供者14例,非血缘HLA相合供者6例。预处理采用氟达拉滨(FLU)、环磷酰胺(CTX)和抗胸腺细胞球蛋白(ATG)方案,移植物抗宿主病(GVHD)预防方案为经典的环孢素A(CsA)联合短程甲氨蝶呤(MTX)及霉酚酸酯(MMF)。对单倍体相合供者采集经G-CSF动员的骨髓及外周血干细胞联合应用;非血缘供者单纯采集外周血干细胞。结果表明:所有患者均获供者型造血重建,粒细胞植活中位时间14(11-20)d,血小板植活中位时间17(13-31)d,2例取得完全供者植入后2个月发生排斥,其中1例进行母亲单倍体相合供者二次移植,达到完全供者持久植入;移植后发生Ⅱ度急性GVHD 4例,慢性GVHD发生7例,其中1例为慢性广泛性GVHD;14例无病生存,所有存活患者最少随访时间在8个月以上,中位随访时间为48个月,血象完全恢复,Kaplan-Meier计算的累积无病生存率为68.9%。结论:采用FLU、CTX和抗淋巴细胞免疫球蛋白进行预处理,用HLA不全相合的亲属供者或HLA相合非血缘供者造血干细胞移植治疗SAA,植入率高,感染发生率降低,获得良好的长期生存疗效。     

New approaches to expand hematopoietic stem and progenitor cells

INTRODUCTION: Hematopoietic stem cells (HSCs) are defined by their capacity to self-renew and to differentiate into all blood cell lineages, and are currently the foundation of HSC transplantation therapy. A variety of methods have recently been explored to find a way to expand hematopoietic stem and progenitor cells (HSCs/PCs) ex vivo in order to improve the efficiency and outcome of HSC transplantation. AREAS COVERED: Recent studies of HSCs/PCs have led to the development of new ways to detect and purify HSCs/PCs and have also revealed several intrinsic and extrinsic factors that control the molecular signals fundamental to self-renewal and differentiation of HSCs. These findings have provided new approaches for expanding HSCs/PCs ex vivo utilizing protein factors and small-molecule compounds (SMCs) and have also demonstrated promising outcomes in clinical trials. EXPERT OPINION: Although further technical innovation is still needed, elucidation of the whole picture of signaling pathways critical to HSCs/PCs and manipulation of such pathways by SMCs could establish efficient, cost-effective, riskless and robust methods for ex vivo expansion of HSCs/PCs. With these efforts, more sophisticated HSC transplantation would be possible in the near future.     

Breaking dogmata to help patients: non-myeloablative haematopoietic stem cell transplantation

Various dogmata have been broken as a consequence of the evolution of knowledge in the area of allogeneic haematopoietic stem cell (HSC) transplantation. The following is now clear: for the successful engraftment of allogeneic HSC, bone marrow ablation of the recipient is not required; HSCs create their own space through graft-versus-host reactions; several malignancies can be eradicated by the graft-versus-tumour effect; HSC allografting can be conducted on an out-patient basis; HSC allografting can be done in aged or debilitated individuals; HSC allografting can be achieved without transfusion of blood products; and the costs of the allografting procedures can be substantially diminished. Despite the fact that HSC allografting with reduced intensity conditioning may be related to several disadvantages, such as mixed chimaerism and relapse of the malignancy, breaking these dogmata has resulted in availability of HSC allografting to a larger number of individuals worldwide, thus offering true curative therapeutic options to patients who otherwise would not qualify to be given these opportunities.     

Breaking dogmata to help patients: non-myeloablative haematopoietic stem cell transplantation

Various dogmata have been broken as a consequence of the evolution of knowledge in the area of allogeneic haematopoietic stem cell (HSC) transplantation. The following is now clear: for the successful engraftment of allogeneic HSC, bone marrow ablation of the recipient is not required; HSCs create their own space through graft-versus-host reactions; several malignancies can be eradicated by the graft-versus-tumour effect; HSC allografting can be conducted on an out-patient basis; HSC allografting can be done in aged or debilitated individuals; HSC allografting can be achieved without transfusion of blood products; and the costs of the allografting procedures can be substantially diminished. Despite the fact that HSC allografting with reduced intensity conditioning may be related to several disadvantages, such as mixed chimaerism and relapse of the malignancy, breaking these dogmata has resulted in availability of HSC allografting to a larger number of individuals worldwide, thus offering true curative therapeutic options to patients who otherwise would not qualify to be given these opportunities.     

Clonal analysis reveals multiple functional defects of aged murine hematopoietic stem cells

Hematopoietic stem cell (HSC) populations change with aging, but the extent to which this is caused by qualitative versus quantitative alterations in HSC subtypes is unclear. Using clonal assays, in this study we show that the aging HSC compartment undergoes both quantitative and qualitative changes. We observed a variable increase of HSC pool size with age, accompanied by the accumulation of predominantly myeloid-biased HSCs that regenerate substantially fewer mature progeny than young myeloid-biased HSCs and exhibit reduced self-renewal activity as measured by long-term secondary transplantation. Old HSCs had a twofold reduction in marrow-homing efficiency and a similar decrease in functional frequency as measured using long-term transplantation assays. Similarly, old HSCs had a twofold reduced seeding efficiency and a significantly delayed proliferative response compared with young HSCs in long-term stromal cell co-cultures but were indistinguishable in suspension cultures. We show that these functional defects are characteristics of most or all old HSCs and are not indicative of a nonfunctional subset of cells that express HSC markers. Furthermore, we demonstrate that cells with functional properties of old HSCs can be generated directly from young HSCs by extended serial transplantation, which is consistent with the possibility that they arise through a process of cellular aging.     

Purified hematopoietic stem cell engraftment of rare niches corrects severe lymphoid deficiencies without host conditioning

In the absence of irradiation or other cytoreductive conditioning, endogenous hematopoietic stem cells (HSCs) are thought to fill the unique niches within the bone marrow that allow maintenance of full hematopoietic potential and thus prevent productive engraftment of transplanted donor HSCs. By transplantation of purified exogenous HSCs into unconditioned congenic histocompatible strains of mice, we show that approximately 0.1-1.0% of these HSC niches are available for engraftment at any given point and find no evidence that endogenous HSCs can be displaced from the niches they occupy. We demonstrate that productive engraftment of HSCs within these empty niches is inhibited by host CD4+ T cells that recognize very subtle minor histocompatibility differences. Strikingly, transplantation of purified HSCs into a panel of severe combined immunodeficient (SCID) mice leads to a rapid and complete rescue of lymphoid deficiencies through engraftment of these very rare niches and expansion of donor lymphoid progenitors. We further demonstrate that transient antibody-mediated depletion of CD4+ T cells allows short-term HSC engraftment and regeneration of B cells in a mouse model of B(-) non-SCID. These experiments provide a general mechanism by which transplanted HSCs can correct hematopoietic deficiencies without any host conditioning or with only highly specific and transient lymphoablation.     

Telomere shortening accompanies increased cell cycle activity during serial transplantation of hematopoietic stem cells

Reactivation of telomerase and maintenance of telomere length can lead to the prevention of replicative senescence in some human somatic cells grown in vitro. To investigate whether telomere shortening might also play a role in the limitation of hematopoietic stem cell (HSC) division capacity in vivo, we analyzed telomere length during serial transplantation of murine HSCs. Southern blot analysis of telomere length in donor bone marrow cells revealed extensive shortening ( approximately 7 kb) after just two rounds of HSC transplantation. The number of cycling HSCs increased after transplantation and remained elevated for at least 4 mo, while the frequency of HSCs in the bone marrow was completely regenerated by 2 mo after transplantation. Direct analysis of telomeres in HSCs by fluorescent in situ hybridization during serial transplantation also revealed a reduction in telomere size. Together, these data show that telomeres shorten during division of HSCs in vivo, and are consistent with the hypothesis that telomere shortening may limit the replicative capacity of HSCs.     

肝干细胞移植在肝病治疗中的应用

背景:目前,肝移植存在供体短缺、手术损伤、手术并发症发生率高以及费用高昂等问题,而肝干细胞移植为终末期肝病的治疗提供了崭新的思路.目的:介绍肝干细胞的来源与分类、肝干细胞移植治疗终末期肝病的研究现状及面临的问题,并展望了其临床应用前景.方法:应用计算机检索中国期刊全文数据库(CNKI:1999/2009)和Medline database数据库(1999/2009)相关文献,检索词分别为"肝干细胞,肝脏疾病,移植"和"hepatic stem cells,liver disease,transplantation",语言分别设定为中文和英文,共检索到87篇文章,阅读文题和摘要进行筛选,选择具有原创性,论点论据可靠且分析全面的与肝干细胞移植临床应用密切相关的文章,排除重复研究及质量较差的文献,最后纳入30篇进行总结综述.结果与结论:肝干细胞可分为肝源性和非肝源性.肝源性肝干细胞包括肝卵圆细胞、成熟肝细胞和间充质干细胞等,非肝源性肝干细胞主要来源于胚胎干细胞、骨髓造血干细胞和胰腺干细胞等.目前肝干细胞治疗肿病的研究尚处在初期阶段,从肝干细胞的发现到分离、纯化、全面鉴定、体外培养、定向分化及临床试验等,仍存在许多难题需要研究解决.不过作为一种新兴的种子细胞来源,肝干细胞不但可替换受损组织,而且可刺激受体组织再生以达到自身修复的目的,所以相比现在临床常用的原位肝移植和生物人工肝而言,肝干细胞在治疗各种原因引起的肝脏疾病中都具有十分广阔的前景.     

New approaches to expand hematopoietic stem and progenitor cells

Introduction: Hematopoietic stem cells (HSCs) are defined by their capacity to self-renew and to differentiate into all blood cell lineages, and are currently the foundation of HSC transplantation therapy. A variety of methods have recently been explored to find a way to expand hematopoietic stem and progenitor cells (HSCs/PCs) ex vivo in order to improve the efficiency and outcome of HSC transplantation.

Areas covered: Recent studies of HSCs/PCs have led to the development of new ways to detect and purify HSCs/PCs and have also revealed several intrinsic and extrinsic factors that control the molecular signals fundamental to self-renewal and differentiation of HSCs. These findings have provided new approaches for expanding HSCs/PCs ex vivo utilizing protein factors and small-molecule compounds (SMCs) and have also demonstrated promising outcomes in clinical trials.

Expert opinion: Although further technical innovation is still needed, elucidation of the whole picture of signaling pathways critical to HSCs/PCs and manipulation of such pathways by SMCs could establish efficient, cost-effective, riskless and robust methods for ex vivo expansion of HSCs/PCs. With these efforts, more sophisticated HSC transplantation would be possible in the near future.