体外诱导的皮肤源性神经干细胞在大鼠受损伤脊髓内的存活、分化和迁移

目的探讨经体外诱导的皮肤源性神经干细胞能否在大鼠脊髓半横断损伤处存活、迁移和分化.方法应用转染绿色荧光蛋白基因新生大鼠的皮肤在体外经分离细胞、培养、诱导增殖以及用免疫细胞化学染色鉴定神经干细胞等过程,将诱导产生的皮肤源性神经干细胞移植入大鼠脊髓半横断损伤处,30 d和60 d后用免疫细胞化学染色法观察移植细胞的存活、迁移和分化.结果皮肤分离细胞在培养10 d时,呈悬浮生长的细胞已增殖成若干细胞球,并呈nestin免疫细胞化学阳性染色,表明是神经干细胞球.在体内可观察到脊髓损伤处有许多带有绿色荧光的移植皮肤源性神经干细胞,有些还迁移到较远的宿主脊髓组织内.存活的移植细胞有些呈现nestin阳性、MAP2阳性及GFAP阳性.结论经体外诱导的皮肤源性神经干细胞能够在受损伤的大鼠脊髓内存活、迁移并分化为神经元样细胞和星形胶质样细胞.     

体外诱导人骨髓间充质干细胞分化为多巴胺能神经元

骨髓间充质干细胞(BMSCs)是存在于骨髓中的非造血干细胞,在体外一定条件下可向神经细胞分化。本实验通过密度梯度离心获取人骨髓中的单个核细胞,贴壁培养纯化BMSCs,并用脑源性神经营养因子(BDNF)、forskolin(FSK)和多巴胺(DA)联合对BMSCs进行诱导,电子显微镜观察诱导后细胞是否具有成熟神经元的超微结构特点;免疫细胞化学和RT-PCR检测DA能神经元分化过程中的标志物酪氨酸羟化酶(TH)的表达以及转录因子Nurr1、Ptx3、和Lmx1b的表达。结果显示:诱导2周后,电镜下可见细胞浆中有大量密集的呈扁平囊状的粗面内质网及其间的一些游离核糖体,以及神经丝。RT-PCR结果显示NSE(neuron specific enolase)、Nurr1、Ptx3、Lmx1b和TH的mRNA均有表达;免疫细胞化学表明诱导2周后TH阳性细胞的表达较诱导3d后明显提高。上述结果表明BDNF、FSK和DA可以在体外诱导人BMSCs定向分化为DA能神经元。     

毛囊培养上清液诱导大鼠骨髓间充质干细胞分化的研究

目的探讨毛囊培养上清液诱导体外培养的大鼠骨髓间充质干细胞(MSCs)向毛囊干细胞横向分化的潜能。方法采用完全贴壁法分离培养大鼠MSCs,取第3代MSCs,用免疫细胞化学染色技术鉴定CD44和CD29。用毛囊培养上清液为条件培养液诱导MSCs,倒置相差显微镜观察细胞形态学变化,对诱导后的细胞进行角蛋白15的免疫细胞化学染色和免疫荧光细胞化学染色,逆转录-聚合酶链反应(RT-PCR)进一步鉴定诱导后细胞角蛋白15的表达。结果体外培养的MSCs,CD44、CD29表达阳性。经毛囊上清液诱导后,免疫细胞化学、免疫荧光细胞化学染色鉴定,部分细胞角蛋白15表达阳性;同时RT-PCR也检测到keratin 15 mRNA的表达。结论体外培养的骨髓间充质干细胞经毛囊培养上清液诱导可以分化为毛囊干细胞样的细胞。     

大鼠骨髓间充质干细胞在海马神经元培养基中的定向分化

目的:观察大鼠骨髓间充质干细胞(BMSCs)在大鼠海马神经元条件培养液中向神经元的分化.方法:以回收的海马神经元Neurobasal加B27作为条件培养基,DMEM加bFGF作为无血清培养基,普通Neurobasal加B27作为神经元基础培养基分别诱导第5代BMSCs 12 h和24 h;免疫细胞化学显色方法鉴定各组神经元样细胞,计数和比较各组阳性细胞阳性率.结果:经海马神经元条件培养基诱导,大鼠BMSCs能够分化为神经元样细胞,免疫细胞化学显色呈微管相关蛋白-Ⅱ(MAP-Ⅱ)和神经元特异性烯醇化酶(NSE)阳性;且阳性比例明显高于其他实验组,差异有统计学意义.结论:BMSCs在海马神经元条件培养基中可以分化为神经元样细胞,其分化效果优于传统DMEM加bFGF无血清培养基和神经元基础培养基.     

大鼠骨髓间质干细胞用肾上腺素类激素诱导为神经细胞的研究

目的:体外诱导大鼠骨髓间质干细胞(MSC)分化为神经细胞。方法:SD大鼠股骨骨髓细胞体外扩增。用肾上腺素、去甲肾上腺素和异丙肾上腺素注射液分别加入无血清L-DMEM诱导MSC分化为神经细胞。免疫细胞化学鉴定有神经元烯醇化酶(NSE)、神经干细胞标志物巢蛋白(nestin)和胶质纤维酸性蛋白(GFAP)表达。结果:大鼠骨髓间质干细胞在体外扩增5-22代,对照组不加任何诱导剂,有53%的神经样细胞。加入肾上腺素、去甲肾上腺素和异丙肾上腺素诱导1-5h,约70%MSC形态转变为典型的神经样细胞。免疫细胞化学显示诱导出的神经样细胞NSE、nestin、GFAP表达阳性。继续培养5d后对照组神经样细胞逐渐凋亡。肾上腺素类各组虽存活6d,但细胞正常形态改变,部分细胞死亡漂浮。一瓶MSC在正常培养至第7代时,自发出现约50%的神经细胞,传至第13代,有约60%的神经细胞(66.5%±6.4%)。结论:骨髓本身可能存在着神经干细胞。大鼠骨髓间质干细胞用肾上腺素类诱导可分化为多种形态的神经细胞。     

大鼠骨髓间充质干细胞分化为神经干细胞

为了观察骨髓间充质干细胞(BMSCs)分化为神经干细胞(NSCs)的能力,本研究通过贴壁法培养大鼠BMSCs,体外培养扩增纯化后,在细胞传代时用含有表皮生长因子(EGF)、碱性成纤维细胞生长因子(bFGF)、N2、B27的DMEM/F12的培养液制成细胞悬液,并进行诱导,观察诱导后细胞的形态及生长情况,用免疫荧光检测形成的细胞球的巢蛋白(nestin)的表达情况;形成的细胞球在含10%血清的培养液中进一步分化。结果显示:BMSCs在含EGF、bFGF、N2、B27的培养液中,逐渐形成nestin表达阳性的细胞球,在含血清的培养液中能分化为神经元样细胞、星形胶质样细胞及少突胶质样细胞。本研究结果提示经纯化的BMSCs能分化为NSCs,并具有进一步分化的能力。     

卵泡抑素诱导骨髓间充质干细胞分化为神经元样细胞

本实验观察了卵泡抑素(follistatin)对骨髓间充质干细胞(BMSCs)向神经细胞分化的影响。利用Percoll密度梯度离心法及贴壁筛选法分离培养和扩增成人的BMSCs,通过流式细胞术分析鉴定BMSCs的纯度,用follistatin诱导第三代生长良好的MSCs向神经元转化,观察分化过程中细胞形态的变化,利用RT-PCR方法检测诱导前后BMSCs的神经元特异性烯醇化酶(NSE)和神经干细胞标记物巢蛋白(Nestin)的表达情况。结果显示:流式分析获得了纯度较高的BMSCs,细胞表达CD29、CD44、CD106和CD166,不表达CD34和CD45。诱导10d后,细胞呈现双极、多极和锥体形的典型神经元细胞形态,并且在mRNA水平证明诱导分化后的细胞与对照组比较NSE和Nestin的表达增加(P<0.05)。上述结果表明follistatin可以在体外诱导人的BMSCs分化为神经样细胞。     

人骨髓间充质干细胞体外定向诱导分化为神经元样细胞

背景:文献报道体外诱导骨髓间充质细胞定向分化为神经元样细胞多应用神经生长因子类多肽制剂,选择纯化学诱导剂尚不多见。目的:建立人骨髓间充质干细胞分离培养体系,体外定向诱导人骨髓间充质干细胞分化为神经元样细胞。方法:密度梯度离心、贴壁培养法和消化时间控制相结合分离纯化人骨髓间充质干细胞并鉴定,采用β-巯基乙醇和二甲基亚砜诱导分化为神经元样细胞,观察细胞形态,通过尼氏染色、NSE和NF-200免疫细胞化学染色对已分化的神经元样细胞进行鉴定和分化率分析。结果与结论:分离得到的骨髓间充质干细胞为成纤维样细胞,可见多个核仁,β-巯基乙醇和二甲基亚砜诱导后,间充质干细胞分化为神经元样细胞,伸出较长轴突样和树突样突起且有分支,诱导后的神经元样细胞胞质中存在着深蓝色颗粒状的尼氏小体,NSE、NF-200免疫荧光细胞化学染色均呈阳性,阳性率分别为(85.6±6.7)%和(73.2±5.6)%。结果证实采用密度梯度离心、贴壁培养法和消化时间控制相结合能够成功分离和培养人骨髓间充质干细胞,人骨髓间充质干细胞能够在诱导剂β-巯基乙醇和二甲基亚砜的诱导下体外诱导分化为神经元样细胞。     

黄连素诱导大鼠骨髓间质干细胞分化为神经元样细胞

目的:黄连素体外定向诱导SD大鼠骨髓间质干细胞分化为神经元样细胞。方法:用全骨髓细胞悬液体外扩增和纯化骨髓间质干细胞。选用第5代以后骨髓间质干细胞进行诱导分化,用含10 μg/L碱性细胞生长因子(bFGF)的完全培养液预诱导24 h,后更换含黄连素的无血清DMEM诱导骨髓间质干细胞分化为神经元样细胞。免疫组化鉴定神经元烯醇酶(NSE)、神经丝蛋白(NF)、胶质纤维酸性蛋白(GFAP)的表达。结果:大鼠骨髓间质干细胞体外扩增第5代后细胞形态达到均一,成梭形。加黄连素诱导1h-8 h,间质干细胞胞体逐渐增大并伸出细长突起,形似神经细胞。免疫组化显示诱导的神经元样细胞NSE、NF表达阳性,GFAP阴性。结论:黄连素可诱导骨髓间质干细胞分化为神经元样细胞。     

骨髓间质干细胞定向分化的实验研究

为了探讨体外定向诱导人骨髓间质干细胞(MSC)分化为神经元样细胞的机制,本研究将分离的人MSC进行体外扩增培养,并观察脑心舒定向诱导MSC分化为类神经元样细胞的效应。在光镜下观察细胞形态,用免疫细胞化学法检测神经细胞特异性抗原标志。结果显示人MSC可通过贴壁法成功分离并可在体外大量扩增。脑心舒诱导120min后大部分MSC转变为神经元样细胞,出现胞体和突起,免疫细胞化学染色NSE、nestin呈阳性和GFAP阴性。上述结果提示人骨髓间质干细胞可在体外诱导分化为神经元样细胞。     

Human dendritic cell subsets display distinct interactions with the pathogenic mould Aspergillus fumigatus

The mould Aspergillus fumigatus is primarily an opportunistic pathogen of immunocompromised patients. Once fungal spores have been inhaled they encounter cells of the innate immune system, which include dendritic cells (DCs). DCs are the key antigen-presenting cells of the immune system and distinct subtypes, which differ in terms of origin, morphology and function.This study has systematically compared the interactions between A. fumigatus and myeloid DCs (mDCs), plasmacytoid DCs (pDCs) and monocyte-derived DCs (moDCs). Analyses were performed by time-lapse video microscopy, scanning electron microscopy, plating assays, flow cytometry, 25-plex ELISA and transwell assays.The three subsets of DCs displayed distinct responses to the fungus with mDCs and moDCs showing the greatest similarities. mDCs and moDCs both produced rough convolutions and occasionally phagocytic cups upon exposure to A. fumigatus whereas pDCs maintained a smooth appearance. Both mDCs and moDCs phagocytosed conidia and germ tubes, while pDCs did not phagocytose any fungi. Analysis of cytokine release and maturation markers revealed specific differences in pro- and anti-inflammatory patterns between the different DC subsets.These distinct characteristics between the DC subsets highlight their differences and suggest specific roles of moDCs, mDCs and pDCs during their interaction with A. fumigatus in vivo.     

造影红细胞对剪切流中肿瘤细胞黏附的影响

目的研究造影红细胞对剪切流环境中白细胞介导肿瘤细胞在内皮细胞上黏附的影响。方法在平行平板流动腔中加入20%比容的造影红细胞,分析不同剪切率(62.5、100、200 s-1)下内皮细胞上黏附白细胞数目、肿瘤细胞与黏附白细胞的碰撞事件以及稳定黏附肿瘤细胞数目的变化。结果造影红细胞促进白细胞在内皮细胞上黏附,增加肿瘤细胞与黏附白细胞的碰撞频率,并最终促进肿瘤细胞在内皮细胞上的黏附,且这一现象在高剪切率(200 s-1)下更为明显;但造影红细胞对肿瘤细胞的黏附效率并无显著影响。结论剪切流中造影红细胞的存在对肿瘤细胞在内皮细胞上的黏附起到促进作用,研究结果为探索癌症治疗方法提供理论基础。     

人类胚胎生殖细胞体外分化为心肌细胞的研究

胚胎生殖（EG）细胞是来源于胚胎原始生殖细胞（PGCs）的多潜能干细胞。采用无饲养层细胞、无细胞因子等的基础培养液（DMEM＋20％NBS＋0．1mM 2Me）培养EG细胞，部分在基础培养液添加10μmol／LRA＋0．75％DMSO或10μmol／L 5-氮胞苷（5-AZA）诱导人类EG细胞向心肌细胞分化，以检测其是否具有向心肌细胞自发分化的能力。9例（8．49％，9／106）胎儿EG细胞在体外分化得到20个节律性心脏跳动样细胞团，其搏动节律为20～120次／min，体外维持节律性搏动最短2d，最长至15d，呈PAS，Myoglobin，α-actin阳性；对K^＋、Ca^＋、肾上腺素等具有与在体心脏相似的反应性；透射电镜观察具有心肌细胞样结构。添加DMSO和RA或5-AZA诱导未得到跳动样心肌细胞，但可提高心肌α-actin免疫组织化学染色阳性率；表明人类胚胎生殖细胞具有向心肌细胞分化的潜能。     

Immunomodulatory effect of DC/CIK combined with chemotherapy in multiple myeloma and the clinical efficacy

To investigate the clinical efficacy of adoptive immunotherapy using dendritic cells (DC) and cytokine-induced killer (CIK) cells combined with chemotherapy in multiple myeloma. The immunomodulatory effect of the therapy was discussed by detecting the levels of peripheral blood T cell subsets and CD4⁺CD25⁺ regulatory cells (Treg). Fifty MM patients were randomly divided into two groups: 24 cases in the simple chemotherapy group and 26 cases in the combined therapy group (chemotherapy plus DC/CIK immunotherapy). The therapeutic efficacy and the proportions of peripheral blood T cell subsets and Treg cells were compared between the two groups. The cellular immunity indicators were also compared, including IL-2, IFN-γ, IL-4, IL-10, AgNORs ratio and TGF-β. After 3 weeks of treatment, the life quality and clinical efficacy of the combined therapy group were superior to those of the simple chemotherapy group (P<0.05). CD3⁺CD8⁺ ratio, CD4⁺CD25⁺ ratio, CD4⁺CD25⁺/CD4⁺ ratio, CD4⁺CD25⁺FoxP3⁺/CD4⁺CD25⁺ ratio, IL-4, IL-10 and TGF-β levels of the combined therapy group were obviously lower than those of the simple chemotherapy group (P<0.05). The CD3⁺CD4⁺/CD3⁺CD8⁺ ratio, AgNOR ratio, IL-2 and IFN-γ level and positive rate of NKG2D in the combined therapy group were significantly higher than those of the simple chemotherapy group (P<0.05). These results indicated better immunomodulatory effect of the combined therapy. DC/CIK immunotherapy combined with chemotherapy has a good clinical efficacy and prospect for MM, reversing the Th1 to Th2 shift and increasing the anti-tumor capacity of the immune system.     

Regulatory and Effector Helper T-Cell Profile after Nerve Xenografting in the Toll-Like Receptor-Deficient Mice

Introduction: The balance between regulatory T cells (Tregs) and effector T help cells (Th cells) is critical for the control of adaptive immune response during nerve transplantation. However, whether the homeostasis of immune regulation between Tregs and Th cells requires toll-like receptor (TLR) signaling is unclear. The aim of this study is to profile the distribution of spleen Tregs and Th cells in a mouse model of nerve xenografting in the TLR2 and NF-κB gene knockout mice.Methods: The sciatic nerve was taken from a SD rat or an allogeneic mouse and transplanted to a right back leg of recipient C57BL/6, TLR2^-/-, or NF-κB^-/- mice by subcutaneous transplantation. After 7 days, the T lymphocytes were then isolated from spleen, stained with phenotyping kits, and analyzed by flow cytometry.Results: The results showed that Tregs were decreased after nerve xenografting in the recipient C57BL/6 mouse. In addition, nerve xenografting also increased the Th1 and Th17 but not the Th2 cell populations. In contrast, amelioration of the Tregs elimination was found in TLR2^-/- and NF-κB^-/- mice after transplantation of the nerve xenograft. Moreover, the mice lacking TLR2 or NF-κB showed attenuation of the increase in Th1 and Th17 cells after nerve xenografting.Conclusions: TLR signaling is involved in T cell population regulation during tissue transplantation. Knock-out of TLR2 and NF-κB prevented Tregs elimination and inhibited Th1- and Th17-driven immune response after nerve xenografting. This study highlighted the potential of inhibiting TLR signaling to modulate T cell-mediated immune regulation to facilitate tolerance to nerve transplantation.     

Regulatory T cells and T helper 17 cells in viral infection

CD4⁺ T cells are the central element of the adaptive immune responses and protect the body from a variety of pathogens. Starting from naive cells, CD4⁺ T cells can differentiate into various effector cell subsets with specialized functions including T helper (Th) 1, Th2, Th17, regulatory T (Treg) and T follicular helper (Tfh) cells. Among them, Tregs and Th17 cells show a strong plasticity allowing the functional adaptation to various physiological and pathological environments during immune responses. Although they are derived from the same precursor cells and their differentiation pathways are interrelated, the terminally differentiated cells have totally opposite functions. Studies have shown that Tregs and Th17 cells have rather complex interplays in viral infection: Th17 cells may contribute to immune activation and disease progression while Tregs may inhibit this process and play a key role in the maintenance of immune homoeostasis, possibly at the cost of compromised viral control. In this review, we take respiratory syncytial virus (RSV), hepatitis B virus (HBV)/hepatitis C virus (HCV) and human immunodeficiency virus (HIV) infections as examples to discuss these interplays and their impacts on disease progression in viral infection.     

Regeneration of dental pulp following pulpectomy by fractionated stem/progenitor cells from bone marrow and adipose tissue

Pulp stem/progenitor cells can induce complete pulp regeneration. However, due to the limited availability of pulp tissue with age, there is a need to examine other sources for fractions of side population (SP) cells. In the present investigation bone marrow and adipose tissues of the same individual were evaluated as alternate sources. Pulp CD31⁻ SP cells have higher migration activity and higher expression of angiogenic/neurotrophic factors than bone marrow and adipose CD31⁻ SP cells. Adipose tissue CD31⁻ SP cell transplantation yielded the same amount of regenerated tissue as pulp derived cells. However, bone marrow CD31⁻ SP cell transplantation yielded significantly less regenerated tissue in pulpectomized root canals in dogs. The rate of matrix formation was much higher in adipose CD31⁻ SP cell transplantation compared to pulp CD31⁻ SP cell transplantation on day 28. Microarray analysis demonstrated similar qualitative and quantitative patterns of mRNA expression characteristic of pulp in the regenerated tissues from all three cell sources. Expression of many angiogenic/neurotrophic factors in the transplanted cells demonstrated trophic effects. Our results demonstrate that bone marrow and adipose CD31⁻ SP cells might be suitable alternative cell sources for pulp regeneration.     

角膜上皮细胞的免疫学特性

目的：探讨角膜上皮细胞刺激淋巴细胞增生的能力和共同刺激通路分子在角膜上皮细胞的表达。方法：体外共同培养人角膜上皮细胞和外周血单个核细胞，免疫组织化学染色方法测定HLAⅡ类抗原、CD40、CD154、CD80和CD86的表达．同时对比角膜移植排斥反应的移植片。荧光辅助细胞筛选、分析、测定CD69的上调。结果：HLAⅡ类抗原在角膜上皮细胞表达，γ-干扰素能够升高共同刺激通路分子CD40和CD80的表达；而且HLAⅡ类抗原和CD40均在角膜移植排斥反应的移植片上被检测出。T淋巴细胞在共同培养系统中被上皮细胞激活。结论：人角膜上皮细胞参与角膜移植排斥反应过程，移植免疫排斥反应被上皮细胞所诱导和初始化，但最终反应作用于内皮细胞。     

雌激素通过调节MSC分泌细胞因子影响其对DC成熟与功能的抑制

目的:本研究试图检测不同浓度17β雌二醇(F2)存在的情况下人胎肺间充质干细胞(MSC)增殖和表型的变化,并分析这种状态的MSC对树突状细胞(DC)成熟和功能影响及其可能的机制.方法:分离培养人胎肺MSC,加入不同浓度E2,在24小时后对MSC进行细胞计数、测定其增殖和贴壁能力,并用流式细胞仪分析MSC表面标志,RT-PCR测定MSC中细胞因子(IL-6、TGF-β和VEGF)mRNA的表达情况.进一步探讨了E2处理24小时后的MSC对DC成熟和功能的影响.结果:分离得到的MSC纯度达到95%以上;E2影响MSC的增殖和贴壁能力,但不影响MSC表面标记的表达;MSC与DC共培养后DC表面CD86、MHCⅡ和CD80的表达均有所降低,而当DC与经E2预处理过的MSC共培后,DC表面MHCⅡ、CD80和CD86的表达回升;高浓度E2作用MSC 24小时后,MSC表达的TGF-β与对照组相比减少,而IL-6和VEGF与对照组相比增加.结论:E2可能通过调节MSC分泌细胞因子的水平,改变MSC对DC的免疫抑制作用.     

Adoptive T cell therapy: Boosting the immune system to fight cancer

Cellular therapies have shown increasing promise as a cancer treatment. Encouraging results against hematologic malignancies are paving the way to move into solid tumors. In this review, we will focus on T-cell therapies starting from tumor infiltrating lymphocytes (TILs) to optimized T-cell receptor-modified (TCR) cells and chimeric antigen receptor-modified T cells (CAR-Ts). We will discuss the positive preclinical and clinical findings of these approaches, along with some of the persisting barriers that need to be overcome to improve outcomes.