脐带血干细胞移植治疗非恶性血液病进展

异基因造血干细胞移植（allo-HSCT）是治愈多种非恶性病的有效方法。脐带血干细胞（UCB）具有免疫原性低、人类白细胞抗原不合耐受性好、移植物抗宿主反应发生率低以及获取相对快捷等特点,可作为非恶性血液疾病患者allo-HSCT的来源。本文简要综述脐血干细胞移植在原发性免疫缺陷病、遗传性骨髓衰竭、遗传代谢病以及自身免疫性疾病等非恶性血液疾病的治疗效果。     

蛛网膜下腔移植脐血干细胞治疗一氧化碳中毒后迟发性脑病的临床研究

目的观察蛛网膜下腔途径移植脐血干细胞治疗一氧化碳中毒后迟发性脑病（DEACMP）的安全性及治疗效果。方法26例DEACMP患者,按治疗方式分两组,其中12例经脐血干细胞移植治疗为治疗组,14例经高压氧治疗为对照组,对每例患者在治疗前和治疗后进行MMSE评分、ADL评分及颅脑CT检查。所有患者连续随访1年,观察预后及有无不良反应。采用两样本t检验、方差分析及卡方检验进行统计学分析。结果治疗组患者在干细胞移植术中均无特殊不适感,术中及术后24h内生命体征平稳,无发热,无穿刺点感染、出血等,术后门诊随访,均未出现移植相关并发症。1年后治疗组患者MMSE评分为25．08±4．10,高于对照组11．7±10．33（t=4．199,P=0．0003）;治疗组ADL评分为93．33±13．37,高于对照组41．07±38．39（t=4．478,P=0．0002）,差异均有统计学意义。治疗组CT检查结果好转率为83．33％,对照组好转率为30．00％两组比较差异有统计学意义（Х^2=4．402,P=0．0359）;治疗组临床痊愈率为50．00％,对照组为7．69％,差异有统计学意义（Х^2=4．055,P=0．0442）;治疗组临床有效率为100．00％,对照组为50．00％差异有统计学意义（Х^2=5．866,P=0．0154）。结论脐血干细胞移植治疗DEACMP疗效优于高压氧治疗,是一种安全有效的生物治疗方法,应得到重视和深入的研究。     

Human umbilical cord blood-derived stromal cells, a new resource in the suppression of acute graft-versus-host disease in haploidentical stem cell transplantation in sublethally irradiated mice

Human umbilical cord blood-derived stromal cells (hUCBDSCs), a novel population isolated from CD34(+) cells by our laboratory, exerted an immunosuppressive effect on xenogenic T cells. This study aimed to investigate whether hUCBDSCs play a critical role in the suppression of acute graft-versus-host disease (aGVHD). The hUCBDSCs were co-cultured with splenocytes (SPCs) of donor C57BL/6 mice. The aGVHD in the recipient (B6×BALB/c) F1 mice was induced by the infusion of bone marrow cells and SPCs from donor mice following sublethal irradiation. The shift in vivo for hUCBDSCs was detected. The proliferation and cell cycle of SPCs were tested by cell counting kit-8 and flow cytometry, respectively. The expression of CD49b natural killer (NK) cells and CD3 T cells was detected by flow cytometry in co-culture and post-transplantation. IL-4, and IFN-γ were detected by ELISA in the serum of co-culture and post-transplantation. The survival time, body weight, clinical score, and histopathological score were recorded for mice post-transplantation. The hUCBDSCs promoted the proliferation of SPCs and significantly increased the ratio of the S and G(2)/M phase (p < 0.05). The hUCBDSCs significantly increased the expression of CD49b NK cells and IL-4 protein and decreased the expression of CD3 T cells and IFN-γ protein both in vitro and in vivo. The survival time of mice with co-transplantation of hUCBDSCs was significantly prolonged, and decreased clinical and histopathological scores were also observed. The hUCBDSCs were continually detected in the target organs of GVHD. These results suggest that hUCBDSCs possess the capability of suppressing aGVHD, possibly via their influence on CD3 T cells, NK cells, and cytokines.     

Human umbilical cord blood serum can replace fetal bovine serum in the culture of mesenchymal stem cells

The potential of mesenchymal stem cells (MSC) to differentiate into different cell types has opened up the possibility of using these cells clinically to treat a variety of disorders. In this study we describe the use of human umbilical cord blood serum (CBS) as a replacement for fetal bovine serum (FBS) for culturing MSC from different sources. MSC from human and swine bone marrow and human umbilical cord blood were cultured in the presence of DMEM/F12 containing either FBS or CBS. Human MSC cultured in presence of FBS or CBS showed typical fibroblast-like morphology, which is characteristic of MSC. 99% of the cells cultured in FBS had a CD73+/CD105+/CD45- phenotype compared to 96% of cells cultured in CBS. Cells cultured in CBS had a significantly higher cell count as compared to cells cultured in FBS. Swine Bone Marrow MSC cultured in the presence of FBS and CBS were morphologically and phenotypically similar. Human umbilical cord blood serum supports the growth of MSC. While no significant differences were observed in the MSC numbers in swine cells cultured in the presence of FBS or CBS, human cells showed a greater proliferation potential in the presence of CBS as compared to FBS. Therefore, CBS can be used as an effective substitute to FBS for developing clinically useful protocols for culturing MSC.     

单倍体相合造血干细胞移植联合脐带间充质干细胞输注治疗儿童重型再生障碍性贫血的临床观察及安全性分析

目的观察单倍体相合造血干细胞移植（hi-HSCT）联合脐带间充质干细胞（hUC-MSC）输注治疗儿童重型再生障碍性贫血（SAA）的临床效果及安全性。 方法整理海军总医院儿科2010年2月至2014年1月收治的11例接受hi-HSCT联合hUC-MSC输注治疗的SAA患儿的临床资料,进行回顾性分析。对其治疗情况、并发症发生情况及生存情况进行观察,总结该治疗方案的临床效果与安全性,以及治疗体会。 结果患儿全部获得造血重建,移植后1个月复查嵌合体均为70% ~ 100%供者嵌合。白细胞植入时间8 ~ 21 d,中位时间为12 d;血小板植入时间10 ~ 24 d,中位时间为15 d。11例患儿中,2例发生Ⅰ度急性移植物抗宿主病（GVHD）,1例发生Ⅲ度急性GVHD,均经相关治疗后好转;1例发生局限性慢性GVHD,经相关治疗后好转;2例发生广泛性慢性GVHD,发生率为18.18%。患儿移植期间均发生不同程度的恶心、呕吐、纳差和发热等症状,给予对症支持治疗后好转。8例（72.73%）发生口腔黏膜炎,2例（18.18%）发生肺部感染,9例（81.82%）发生病毒感染,2例（18.18%）发生腹泻,均经综合治疗后好转。11例患儿随访时间12 ~ 29个月,中位随访时间16个月,截止末次随访时1例因广泛性慢性GVHD接受持续治疗,2例接受免疫抑制剂减量治疗,其余4例均停用免疫抑制剂;1例患儿因家属自行停用环孢素A发生排异死亡。 结论hi-HSCT联合hUC-MSC输注治疗儿童SAA具有良好临床疗效,值得进一步关注。     

A framework to gauge the epidemic potential of plant pathogens in environmental reservoirs: the example of kiwifruit canker

New economically important diseases on crops and forest trees emerge recurrently. An understanding of where new pathogenic lines come from and how they evolve is fundamental for the deployment of accurate surveillance methods. We used kiwifruit bacterial canker as a model to assess the importance of potential reservoirs of new pathogenic lineages. The current kiwifruit canker epidemic is at least the fourth outbreak of the disease on kiwifruit caused by Pseudomonas syringae in the mere 50 years in which this crop has been cultivated worldwide, with each outbreak being caused by different genetic lines of the bacterium. Here, we ask whether strains in natural (non‐agricultural) environments could cause future epidemics of canker on kiwifruit. To answer this question, we evaluated the pathogenicity, endophytic colonization capacity and competitiveness on kiwifruit of P. syringae strains genetically similar to epidemic strains and originally isolated from aquatic and subalpine habitats. All environmental strains possessing an operon involved in the degradation of aromatic compounds via the catechol pathway grew endophytically and caused symptoms in kiwifruit vascular tissue. Environmental and epidemic strains showed a wide host range, revealing their potential as future pathogens of a variety of hosts. Environmental strains co‐existed endophytically with CFBP 7286, an epidemic strain, and shared about 20 virulence genes, but were missing six virulence genes found in all epidemic strains. By identifying the specific gene content in genetic backgrounds similar to known epidemic strains, we developed criteria to assess the epidemic potential and to survey for such strains as a means of forecasting and managing disease emergence.     

Extracorporeal photopheresis as first-line strategy in the treatment of acute graft-versus-host disease after hematopoietic stem cell transplantation: A single-center experience

Background aims: Corticosteroids are the standard first-line treatment for acute graft-versus-host disease (aGVHD), but they are associated with many complications, and less than half of patients have a sustained response.Methods: To improve outcomes, we performed a retrospective study to analyze the efficacy of the addition of extracorporeal photopheresis (ECP) to low-dose corticosteroids in 37 adult patients (median age, 57 years) with skin-predominant aGVHD (grade I, n = 17; grade II, n = 18; and grade III, n = 2). All patients received ECP in combination with 1 mg/kg prednisone (n = 26) or topical steroids (n = 11).Results: Overall response rate was 81% after a median of three ECP procedures (range, 2–8), including 22 complete responses (CR, 59%) and eight very good partial responses (VGPR, 22%). The 11 patients treated with topical corticosteroids achieved CR. Furthermore, 16 (62%) patients reached prednisone withdrawal at a median of 100 days (range, 42–174 days) after its initiation. Eighteen patients developed chronic GVHD (cGVHD); 11 of them (who were in CR of aGVHD) had a new-onset cGVHD, and seven experienced progressive cGVHD (five non-responding and two VGPR patients). A second-line immunosuppressive treatment was initiated in only five (14%) non-responding patients. With a median follow-up of 31 months (range, 6–57 months) 2-year overall survival and non-relapse mortality were 74% and 11%, respectively.Conclusions: Overall, the combination of low-dose corticosteroids and ECP appear to be safe and effective for first-line treatment of skin predominant aGVHD.     

Biofilms as a microbial hazard in the food industry: A scoping review

Biofilms pose a serious public health hazard with a significant economic impact on the food industry. The present scoping review is designed to analyse the literature published during 2001–2020 on biofilm formation of microbes, their detection methods, and association with antimicrobial resistance (if any). The peer-reviewed articles retrieved from 04 electronic databases were assessed using PRISMA-ScR guidelines. From the 978 preliminary search results, a total of 88 publications were included in the study. On analysis, the commonly isolated pathogens were Listeria monocytogenes, Staphylococcus aureus, Salmonella spp., Escherichia coli, Bacillus spp., Vibrio spp., Campylobacter jejuni and Clostridium perfringens. The biofilm-forming ability of microbes was found to be influenced by various factors such as attachment surfaces, temperature, presence of other species, nutrient availability etc. A total of 18 studies characterized the biofilm-forming genes, particularly for S. aureus, Salmonella spp., and E. coli. In most studies, polystyrene plate and/or stainless-steel coupons were used for biofilm formation, and the detection was carried out by crystal violet assays and/or by plate counting method. The strain-specific significant differences in biofilm formation were observed in many studies, and few studies carried out analysis of multi-species biofilms. The association between biofilm formation and antimicrobial resistance was not clearly defined. Further, viable but non-culturable form of the foodborne pathogens is posing an unseen (by conventional cultivation techniques) but potent threat to the food safety. The present review recommends the need for carrying out systematic surveys and risk analysis of biofilms in food chain to highlight the evidence-based public health concerns, especially in regions where microbiological food hazards are quite prevalent.     

Delta-like 1 serves as a new target and contributor to liver fibrosis down-regulated by mesenchymal stem cell transplantation

Chronic liver injury always progresses to fibrosis and eventually to cirrhosis, a massive health care burden worldwide. Delta-like 1 (Dlk1) is well known as an inhibitor of adipocyte differentiation. However, whether it is involved in liver fibrosis remains unclear. Here, we provide the first evidence that Dlk1 is a critical contributor to liver fibrosis through promoting activation of hepatic stellate cells (HSCs) during chronic liver injury. We found that upon liver injury, Dlk1 was dramatically induced and initially expressed in hepatocytes and then into the HSCs by a paracrine manner. It leads to the activation of HSCs, which is considered to be a pivotal event in liver fibrogenesis. Two forms (～50 and ～25 kDa) of the Dlk1 protein were detected by Western blot analysis. In vitro administration of Dlk1 significantly promoted HSC activation, whereas in vivo knockdown of Dlk1 dramatically inhibited HSC activation and the subsequent fibrosis. The large soluble form (～50 kDa) of Dlk1 was shown to contribute to HSC activation. We were encouraged to find the Dlk1-promoted HSC activation and liver fibrosis can be depressed by transplantation of bone marrow-mesenchymal stem cells (BM-MSCs). Furthermore, we demonstrated that FGF2 was up-regulated in BM-MSCs under injury stimulation, and it probably participated in the inhibition of Dlk1 by BM-MSCs. Our findings provide a novel role of Dlk1 in liver fibrosis leading to a better understanding of the molecular basis in fibrosis and cirrhosis and also give insights into the cellular and molecular mechanisms of MSC biology in liver repair.     

The time is now: moving toward virus-specific T cells after allogeneic hematopoietic stem cell transplantation as the standard of care

Adoptive immunotherapy—in particular, T-cell therapy—has recently emerged as a useful strategy with the potential to overcome many of the limitations of antiviral drugs for the treatment of viral complications after hematopietic stem cell transplantation. In this review, we briefly summarize the current methods for virus-specific T-cell isolation or selection and we report results from clinical trials that have used these techniques, focusing specifically on the strategies aimed to broaden the application of this technology.     

Poly(lactic-co-glycolic acid) nanosphere as a vehicle for gene delivery to human cord blood-derived mesenchymal stem cells: comparison with polyethylenimine

Polyethylenimine (PEI) is one of the most extensively studied non-viral vectors but its cytotoxicity limits its clinical value. PLGA nanospheres are biocompatible and can facilitate sustained release of plasmid DNA. This study compares the cytotoxicity and long-term transgene expression between PLGA nanosphere and PEI. PLGA nanospheres were significantly less cytotoxic than PEI at various concentrations. PLGA nanospheres induced significantly higher transgene expression in vitro for a longer duration (21 days) than PEI. We conclude that PLGA nanospheres have potential as gene delivery vehicles for use in gene therapy for diseases in which a long-term therapeutic gene expression regimen is necessary.     

Efficacy and safety of autologous stem cell transplantation for decompensated liver cirrhosis: A retrospective cohort study

AIM To evaluate the long-term efficacy and safety of autologous stem cell transplantation(SCT) for decompensated liver cirrhosis.METHODS Consecutive patients with decompensated liver cirrhosis were included and assigned into the SCT group and non-transplantation(non-SCT) group according to whether they received SCT treatment. Patients werefollowed up for ten years. The long-term survival rate and incidence of hepatocellular carcinoma(HCC) were compared between groups.     

Disruption of the viral polymerase complex assembly as a novel approach to attenuate influenza A virus

To develop a novel attenuation strategy applicable to all influenza A viruses, we targeted the highly conserved protein-protein interaction of the viral polymerase subunits PA and PB1. We postulated that impaired binding between PA and PB1 would negatively affect trimeric polymerase complex formation, leading to reduced viral replication efficiency in vivo. As proof of concept, we introduced single or multiple amino acid substitutions into the protein-protein-binding domains of either PB1 or PA, or both, to decrease binding affinity and polymerase activity substantially. As expected, upon generation of recombinant influenza A viruses (SC35M strain) containing these mutations, many pseudo-revertants appeared that partially restored PA-PB1 binding and polymerase activity. These polymerase assembly mutants displayed drastic attenuation in cell culture and mice. The attenuation of the polymerase assembly mutants was maintained in IFNα/β receptor knock-out mice. As exemplified using a H5N1 polymerase assembly mutant, this attenuation strategy can be also applied to other highly pathogenic influenza A virus strains. Thus, we provide proof of principle that targeted mutation of the highly conserved interaction domains of PA and PB1 represents a novel strategy to attenuate influenza A viruses.     

Anticarcinogenic impact of extracellular vesicles (exosomes) from cord blood stem cells in malignant melanoma: A potential biological treatment

Incidence of Malignant Melanoma has become the 5th in the UK. To date, the major anticancer therapeutics include cell therapy, immunotherapy, gene therapy and nanotechnology-based strategies. Recently, extracellular vesicles, especially exosomes, have been highlighted for their therapeutic benefits in numerous chronic diseases. Exosomes display multifunctional properties, including inhibition of cancer cell proliferation and initiation of apoptosis. In the present in vitro study, the antitumour effect of cord blood stem cell (CBSC)-derived exosomes was confirmed by the CCK-8 assay (p < 0.05) on CHL-1 melanoma cells and improve the repair mechanism on lymphocytes from melanoma patients. Importantly, no significant effect was observed in healthy lymphocytes when treated with the exosome concentrations at 24, 48 and 72 h. Comet assay results (OTM and %Tail DNA) demonstrated that the optimal exosome concentration showed a significant impact (p < 0.05) in lymphocytes from melanoma patients whilst causing no significant DNA damage in lymphocytes of healthy volunteers was 300 μg/ml. Similarly, the Comet assay results depicted significant DNA damage in a melanoma cell line (CHL-1 cells) treated with CBSC-derived exosomes, both the cytotoxicity of CHL-1 cells treated with CBSC-derived exosomes exhibited a significant time-dependent decrease in cell survival. Sequencing analysis of CBSC exosomes showed the presence of the let-7 family of miRNAs, including let-7a-5p, let-7b-5p, let-7c-5p, let-7d-3p, let-7d-5p and two novel miRNAs. The potency of CBSC exosomes in inhibiting cancer progression in lymphocytes from melanoma patients and CHL-1 cells whilst causing no harm to the healthy lymphocytes makes it a potential candidate as an anticancer therapy.     

Refractory disseminated fusariosis by Fusarium verticillioides in a patient with acute myeloid leukaemia relapsed after allogeneic hematopoietic stem cell transplantation: A case report and literature review

BackgroundFusarium species are among the leading fungal pathogens to cause invasive mould infections in patients with hematopoietic malignancy. The Fusarium species most frequently involved in human infections are Fusarium solani, Fusarium oxysporum and Fusarium verticillioides. However, identification is a cumbersome and time-consuming task. Fusarium is resistant in vitro to many of the antifungal agents and the management of fusariosis is not well defined.ObjectivesTo emphasise the difficulty of identifying Fusarium spp. by conventional methods and the need of new rapid molecular tests to achieve earlier diagnosis and appropriate therapy.MethodsA disseminated Fusarium infection due to F. verticillioides was documented in a neutropenic refractory patient with acute myeloid leukaemia, relapsed after allogeneic hematopoietic stem cell transplantation.ResultsThe patient died despite liposomal amphotericin B and voriconazole combination and “in vitro” susceptibility of agents employed. Morphological and molecular identification of F. verticillioides was obtained only after the death of the patient.ConclusionsThis case highlights the poor outcome of an invasive fungal disease caused by Fusarium in aplastic patients. Identification of members of Fusarium genus remains restricted to selected laboratories and should be introduced into routine mycological diagnostics. In immunocompromised patients, diagnosis of fusariosis is directly related to prompt diagnosis and to patient's status. Current diagnosis methods and therapeutic options are discussed.     

WJSC 6th Anniversary Special Issues（1）:Hematopoietic stem cell transplantation Allogeneic hematopoietic cell transplant for acute myeloid leukemia:Current state in 2013 and future directions

Acute myeloid leukemia(AML)represents a heterogeneous group of high-grade myeloid neoplasms of the elderly with variable outcomes.Though remissioninduction is an important first step in the management of AML,additional treatment strategies are essential to ensure long-term disease-free survival.Recent pivotal advances in understanding the genetics and molecular biology of AML have allowed for a risk-adapted approach in its management based on relapse-risk.Allogeneic hematopoietic cell transplantation(allo-HCT)represents an effective therapeutic strategy in AML providing the possibility of cure with potent graft-versus-leukemia reactions,with a demonstrable survival advantage in younger patients with intermediate-or poor-risk cytogenetics.Herein we review the published data regarding the role of allo-HCT in adults with AML.We searched MEDLINE/PubMed and EMBASE/Ovid.In addition,we searched reference lists of relevant articles,conference proceedings and ongoing trial databases.We discuss the role of allo-HCT in AML patients stratified by cytogenetic-and molecular-risk in first complete remission,as well as allo-HCT as an option in relapsed/refractory AML.Besides the conventional sibling and unrelated donor allografts,we review the available data and recent advances for alternative donor sources such as haploidentical grafts and umbilical cord blood.We also discuss conditioning regimens,including reduced intensity conditioning which has broadened the applicability of allo-HCT.Finally we explore recent advances and future possibilities and directions of allo-HCT in AML.Practical therapeutic recommendations have been made where possible based on available data and expert opinion.