Immunisation with the BCG and DTPw vaccines induces different programs of trained immunity in mice

In addition to providing pathogen-specific immunity, vaccines can also confer nonspecific effects (NSEs) on mortality and morbidity unrelated to the targeted disease. Immunisation with live vaccines, such as the BCG vaccine, has generally been associated with significantly reduced all-cause infant mortality. In contrast, some inactivated vaccines, such as the diphtheria, tetanus, whole-cell pertussis (DTPw) vaccine, have been controversially associated with increased all-cause mortality especially in female infants in high-mortality settings. The NSEs associated with BCG have been attributed, in part, to the induction of trained immunity, an epigenetic and metabolic reprograming of innate immune cells, increasing their responsiveness to subsequent microbial encounters. Whether non-live vaccines such as DTPw induce trained immunity is currently poorly understood. Here, we report that immunisation of mice with DTPw induced a unique program of trained immunity in comparison to BCG immunised mice. Altered monocyte and DC cytokine responses were evident in DTPw immunised mice even months after vaccination. Furthermore, splenic cDCs from DTPw immunised mice had altered chromatin accessibility at loci involved in immunity and metabolism, suggesting that these changes were epigenetically mediated. Interestingly, changing the order in which the BCG and DTPw vaccines were co-administered to mice altered subsequent trained immune responses. Given these differences in trained immunity, we also assessed whether administration of these vaccines altered susceptibility to sepsis in two different mouse models. Immunisation with either BCG or a DTPw-containing vaccine prior to the induction of sepsis did not significantly alter survival. Further studies are now needed to more fully investigate the potential consequences of DTPw induced trained immunity in different contexts and to assess whether other non-live vaccines also induce similar changes.     

Cost-effective differentiation of hepatocyte-like cells from human pluripotent stem cells using small molecules

Significant efforts have been invested into the differentiation of stem cells into functional hepatocyte-like cells that can be used for cell therapy, disease modeling and drug screening. Most of these efforts have been concentrated on the use of growth factors to recapitulate developmental signals under in vitro conditions. Using small molecules instead of growth factors would provide an attractive alternative since small molecules are cell-permeable and cheaper than growth factors. We have developed a protocol for the differentiation of human embryonic stem cells into hepatocyte-like cells using a predominantly small molecule–based approach (SM-Hep). This 3 step differentiation strategy involves the use of optimized concentrations of LY294002 and bromo-indirubin-3’-oxime (BIO) for the generation of definitive endoderm; sodium butyrate and dimethyl sulfoxide (DMSO) for the generation of hepatoblasts and SB431542 for differentiation into hepatocyte-like cells. Activin A is the only growth factor required in this protocol. Our results showed that SM-Hep were morphologically and functionally similar or better compared to the hepatocytes derived from the growth-factor induced differentiation (GF-Hep) in terms of expression of hepatic markers, urea and albumin production and cytochrome P450 (CYP1A2 and CYP3A4) activities. Cell viability assays following treatment with paradigm hepatotoxicants Acetaminophen, Chlorpromazine, Diclofenac, Digoxin, Quinidine and Troglitazone showed that their sensitivity to these drugs was similar to human primary hepatocytes (PHHs). Using SM-Hep would result in 67% and 81% cost reduction compared to GF-Hep and PHHs respectively. Therefore, SM-Hep can serve as a robust and cost effective replacement for PHHs for drug screening and development.     

超顺磁性氧化铁标记大鼠骨髓基质细胞经门静脉移植MRI活体示踪的研究

目的观察1．5T场强MRI联合动物专用线圈是否可以活体示踪经门静脉移植的纳米级超顺磁性氧化铁颗粒标记的骨髓基质细胞（bone marrow stromal cells BMSCs），为介人性门静脉骨髓基质细胞移植治疗终末期肝脏疾病的研究提供进一步的依据。方法供体大鼠5只，梯度密度离心分离BMSCs，纳米级超顺磁性氧化铁颗粒和脂质体转染BMSCs，体外经普鲁士蓝染色和HE染色确定细胞标记率。受体大鼠15只，分为5组，分别为对照组和纳米级超顺磁性氧化铁颗粒标记的骨髓基质细胞经门静脉移植人正常大鼠肝脏后2h、3d、7d及2周组。1．5T场强MRI联合动物专用线圈行T1W、T2W和T2＊序列扫描，观察肝脏信号改变情况，与对照组比较，并且与组织切片对照。结果纳米级超顺磁性氧化铁颗粒和脂质体转染BMSCs，细胞标记率〉95％。经门静脉移植人正常大鼠肝脏后，T2＊序列扫描显示经标记的BMSCs在肝内显示弥漫性的结节性低信号影，移植后2h到2周均可见到细胞在受体肝脏内存在，组织学切片显示信号缺失部位与铁颗粒标记细胞相一致。结论纳米级超顺磁性铁氧体颗粒标记的大鼠BMSCs经门静脉移植后可以通过1、5T场强行MRI活体示踪，为临床干细胞移植的应用提供可行的示踪方法。     

转TrkC基因神经干细胞移植对脊髓损伤的治疗作用

目的 研究转酪氨酸激酶C（tyrosine kinase C，TrkC）基因神经干细胞（neural stem cells，NSCs）移植治疗脊髓损伤的作用。方法 60只SD大鼠随机分成正常对照组（A组）、脊髓半切组（B组）、NSCs移植组（C组）、NSCs移植＋神经营养素（NT）-3局部使用（D）组、转TrkC基WNSCs移植组（E组）和转TrkC基因NSCs移植＋NT-3局部使用组（F组），每组10只。脊髓损伤后第9天进行细胞移植。各组大鼠在细胞移植后2个月，行体感诱发电位（SEP）和运动诱发电位（MEP）检查以及脊髓运动功能（BBB）评分。结果 细胞移植后2个月SEP和MEP发生潜伏期和峰峰波幅以及右后肢BBB评分的恢复均以下组最佳，与其他各组比较，差异有统计学意义（P＜ 0．05，0．01）。结论在局部给予的NT-3作用下，转TrkC基因NSCs能较好地促进损伤脊髓功能的恢复。     

用心肌灌注显像靶心图定量分析评价AMI患者骨髓干细胞移植术疗效

目的 探讨靶心图上心肌灌注缺损区定量分析方法的可靠性、重复性及应用价值。方法 16例急性心肌梗死（AMI）行自体骨髓单个核细胞移植治疗的住院患者，于治疗前、治疗后45和90d行^99Tc^m-MIBI静息心肌灌注显像。在靶心图上勾画缺损区（在左心室靶心图中放射性计数低于40％的区域），并进行定量分析。结果 （1）不同操作者所得ROI结果之间的差异无统计学意义（t=0．52，P〉0．05）。（2）治疗后45d心肌灌注缺损区面积较治疗前缩小34．32％，差异有统计学意义（t=2．83，P〈0．05）；治疗后90d心肌灌注缺损区面积较治疗后45d缩小14．77％，差异有统计学意义（t=2．51，P〈0．05）。示自体骨髓单个核细胞移植对缺血心肌的恢复有一定疗效，能够缩小梗死面积，且自体骨髓单个核细胞冠状动脉内移植治疗AMI的疗效在移植后早期（45d内）即有体现。（3）面积百分比是观察心肌灌注变化的重要定量指标。结论 该方法对心肌病变范围及严重程度能准确定量；对评价AMI骨髓于细胞移植术疗效有一定的价值。     

种子细胞双相接种技术促进组织工程骨体外成熟的研究

目的 比较观察双相接种法和静置接种法构建组织工程骨对种子细胞增殖、分化和成骨表达的影响。方法 取健康志愿者骨髓，密度梯度离心法分离骨髓间充质干细胞并进行体外扩增、诱导分化，然后应用双相接种法和静置接种法与脱钙骨基质（DBM）复合构建组织工程骨，体外培养3周，用倒置显微镜、扫描电镜观察细胞密度、形态及基质分泌情况，并在不同时相点测定组织块中DNA含量、碱性磷酸酶（ALP）活性及钙含量变化。结果 倒置显微镜下双相接种法构建的组织块可见大量具有一定折光性的梭形细胞存在于胶原基质中。扫描电镜见双相接种法构建的组织块切面较平坦，孔隙较小，细胞包埋在胶原中，而静置接种法构建的组织块可见细胞、细胞外基质较少。在体外培养过程中，双相接种法组织块中细胞的DNA含量、ALP活性均高于静置接种法，钙含量在培养2周后高于静置接种法。结论 双相接种法是一种高效的组织工程骨构建方法，有利于提高接种效率和促进组织工程骨的体外成熟。     

ABO血型不合的异基因造血干细胞移植--2例报告附文献复习

探讨ABO血型不合的异基因造血干细胞移植 (Allo -HSCT)的造血问题。方法 :对 2例患者分别进行异基因外周血造血干细胞移植 (Allo -PBSCT)及脐血造血干细胞移植 (CBSCT) ,用血细胞分离机或 6 %羟乙基淀粉去除移植物中的红细胞 ,定期检测受者血型 ,根据情况输注血细胞。结果 :2例患者全部获得造血重建 ,未出现溶血反应。结论 :ABO血型不合可以进行Allo -HSCT ,去除供者移植物中的红细胞能有效地防止急性溶血反应的发生 ,定期检测受者血型 ,及时调整输血方案有重要的临床意义。     

Reelin expression is upregulated following ocular tissue injury

Purpose Reelin is important in the guidance of neuronal stem cells in the central nervous system during normal development. We wished to determine whether reelin is expressed in the retina and cornea after injury. Methods Mice underwent laceration of their retina as well as corneal epithelial debridement. The mice were sacrificed at 3 days, and eyes were fixed and stained for reelin expression and reelin messenger ribonucleic acid (mRNA). Results In normal eyes, reelin was expressed only at very low levels in the ganglion cell layer of the retina and the endothelial cell layer of the cornea. In injured eyes, there was marked expression in reelin immunoreactivity in the retina and cornea. Reelin gene expression was seen in the retina and cornea. Conclusions Reelin is expressed during normal retinogenesis. This study shows that reelin is also upregulated following injury to the retina and cornea. The expression of reelin following injury suggests that reelin may play an important role in regulating stem cell trafficking in neuronal and nonneuronal tissues following injury similar to its role in normal organogenesis. For consideration of publication in Graefe’s Archive for Clinical and Experimental Ophthalmology.     

神经干细胞移植延缓失神经肌萎的作用机制

Objective To study the effect and mechanism of transplanting spinal fetal neural stem cells (NSCs) into the peripheral nerve for delaying muscle denervation atrophy. Methods Spinal. fetal NSCs were separated from spinal cord of enceinte 10 to 12 days SD rats, cultured and purified. After three passages, the formed NSC spheres were blew into single cell suspension ( 106/μl×5 μl) and transplanted into the distal part of the transected tibial nerve. 5 μl of cell culture medium was injected into the distal tibial nerve in the control group. Three and 5 months after the transplantation, the distal part of the tibial nerve and the triceps suraes were harvested and identified with specific markers, by means of indirect immunofluorescent staining to evaluate survival and differentiation of transplanted NSCs in the nerve, and to observe the neuromuscular junctions.Results Compare to the control group, atrophy of the triceps suraes muscle was less severe 3 and 5 months after NSCs transplantation. Postsynaptic membrane was also better preserved in NSCs transplanted group. Five months after NSCs transplantation, new synapses (neuromuscular junction) formed in the denervated muscle.Conclusion NSCs transplantation can delay atrophy denervated muscles. NSCs transplantation can not only maintain the structure of postsynaptic membrane, but also form new synapse with the denervated muscle.