基底硬度对肝细胞与肝癌细胞迁移行为的影响

目的通过比较不同硬度基底对肝细胞和肝癌细胞迁移特征的影响,研究肿瘤细胞迁移行为变化的成因。方法运用免疫荧光染色、形态学分析法和Transwell侵袭实验,观察不同硬度基底上HCCLM3和L02细胞的形态特征及对细胞运动能力进行检测和定量分析。结果 (1)相对于极软(0.5 kPa)和极硬(玻璃)基底,HCCLM3和L02细胞在较软基底(4 kPa)上具有较高的迁移速率和迁移净距离,且L02细胞表现出高的迁移效率。(2)HC-CLM3和L02细胞在不同硬度基底上均方位移趋势一致,较软基底上L02细胞具有较高的方向持续能力。(3)0.5和1 mg/mL三维胶原基质中,HCCLM3细胞穿透基底膜的个数分别显著多于L02细胞穿透基底膜的个数;加入40μg/mL水解酶抑制剂GM6001后,HCCLM3细胞穿透基底膜的个数显著增加,而L02细胞穿透基底膜的个数显著减少。结论 (1)二维较软基底上,L02细胞因有较高的方向持续能力而表现出高的迁移效率。(2)三维胶原基质中,HCCLM3细胞以不同迁移模式适应周围环境,从而表现出更大的侵袭能力。     

肝癌细胞"重叠生长"局部成因初探

探索肝癌细胞"重叠生长"形成过程及其成因.运用显微形态学观察、计算机图像处理技术和统计学分析,以及细胞力学和生化检测等研究手段对肝癌细胞原位生长信息进行量化表征.结果发现:(1)肝癌细胞变形调节能力较正常肝细胞强;(2)对"重叠生长"斑进行负压吸吮时,斑片从基底脱落,其下方未见铺展细胞;(3)肝癌细胞株HepG2的整合素表达明显高于正常肝细胞株L02;(4)纤维连接蛋白(Fibronectin, Fn)对肝癌细胞表达整合素β1有下调作用,Fn裱衬基底后,细胞黏附力和形态稳定性增高,圆细胞产生与聚集减少.由此得出(1)所谓"重叠生长层"实际上是由大量圆细胞聚集排列构成;(2)圆细胞产生与整合素β1表达异常及其对细胞黏附特性的影响相关;(3)肝癌细胞"重叠层"的形成与细胞频发形变诱导的圆细胞聚集相关.     

不同基底硬度对人肝癌细胞黏附、铺展和迁移的影响

目的研究不同基底硬度对肝癌细胞黏附、铺展和迁移行为的影响及对细胞骨架装配方式和细胞表面黏附蛋白整合素β1表达的调控,探讨基底的力学特性在肝癌细胞恶性转移过程中的作用。方法通过调节丙聚酰胺和双丙烯酰胺的比率制备不同硬度的聚丙烯酰胺基底,并在基底表面裱衬2.5μg/mL纤维连接蛋白为细胞提供黏附位点;用显微观察并记录不同硬度基底上细胞黏附、铺展和迁移的变化,并用Image J软件定量分析;分别运用免疫荧光和流式细胞仪的方法检测不同基底硬度对肝癌细胞骨架装配和细胞表面整合素β1表达的影响。结果硬基底利于肝癌细胞的黏附和铺展并缩短细胞的铺展时间。过软(1.1 kPa)或过硬(玻璃)的基底都不利于肝癌细胞的迁移,肝癌细胞在中间硬度的基底上(10.7 kPa)迁移速率最高。硬基底促进细胞骨架的装配和整合素β1表达。结论基底硬度通过调节细胞骨架装配和整合素的表达从而影响肝癌细胞的黏附、铺展和迁移。     

miR-101-3p通过靶向抑制斯坦尼钙调节蛋白1(STC1)促进巨噬细胞对人肝癌细胞的吞噬作用

目的 探究miR-101-3p能否促进THP-1巨噬细胞对HCCLM3人肝癌细胞的吞噬作用及其机制。方法 通过慢病毒包装、感染和抗性筛选，获得绿色荧光蛋白(GFP)标记并过表达miR-101-3p的HCCLM3人肝癌细胞稳转系(HCCLM3^GFP-miR-101-3p),同时使用佛波酯(PMA)诱导THP-1细胞贴壁分化为M0型巨噬细胞。将两者共培养24 h后收集细胞，运用荧光激活细胞分选法(FACS)检测巨噬细胞吞噬效率。实时定量PCR检测斯坦尼钙调节蛋白1(STC1)、钙网蛋白(CRT)的mRNA表达水平，免疫荧光染色法检测CRT的表达和分布，Western blot法检测STC1、 CRT的蛋白表达水平，双荧光素酶报告基因实验分析miR-101-3p与靶基因的靶向调控关系。结果 过表达miR-101-3p促进THP-1巨噬细胞对HCCLM3肝癌细胞的吞噬作用，miR-101-3p通过靶向STC1进而上调HCCLM3细胞膜表面CRT的表达。结论 miR-101-3p通过靶向抑制STC1进而促进HCCLM3细胞膜表面CRT的表达，增强巨噬细胞对肝癌细胞的吞噬作用...     

mfn2基因转染对非酒精性脂肪肝细胞线粒体功能的影响

目的:研究线粒体融合蛋白基因2(mfn2)对非酒精性脂肪肝细胞线粒功能的影响。方法:利用脂质体lipofectamine2000将mfn2基因荧光表达载体(pEGFP-mfn2)转染肝细胞株L02,并采用油酸诱导L02建立非酒精性脂肪性肝细胞模型,RT-PCR及Western blotting检测细胞mfn2mRNA和蛋白的表达;荧光素酶ADP/ATP发光法检测各组细胞内ATP水平,荧光探针DCFH-DA测定细胞活性氧(ROS)生成水平;JC-1标记细胞线粒体,流式细胞仪检测线粒体跨膜电位(Δψm)的变化。结果:转染mfn2基因的L02可以稳定高表达mfn2mRNA及蛋白,转染后L02内ATP浓度及线粒体跨膜电位显著升高(P0.05),而ROS生成水平则显著下降(P0.05);经油酸诱导肝细胞脂肪变性后,L02mfn2表达受抑制,各组细胞内ATP浓度及线粒体跨膜电位均显著下降(P0.01),而ROS生成水平较前均显著升高(P0.01),但转染组细胞内ATP下降水平以及线粒体跨膜电位下降幅度均显著低于未转染组,而未转染组ROS升高程度则显著高于转染组(P0.01)。结论:外源性mfn2基因转染可以抑制油酸诱导的肝细胞内ATP浓度和线粒体跨膜电位的下降以及ROS生成的增加。     

基底硬度与细胞因子TGF-β1协同作用对肝细胞表型的影响

目的通过建立与肝组织生理和病理硬度相当的体外培养模型,探讨基底硬度和TGF-β1协同作用对肝细胞表型变化的影响。方法采用免疫荧光显微观测技术及Western Blotting等试验方法,研究肝细胞在不同硬度梯度的聚丙烯酰胺基底膜上的细胞形态调整、运动变化特征、骨架构象以及整合素、E-钙粘素、白蛋白和alpha-平滑肌动蛋白表达的差别,并通过图像分析软件对上述结果进行定量分析。结果 3.6 kPa基底膜上单个分散细胞运动变形活跃,但群体细胞极化变小,肌动蛋白沿皮质下呈环状排列,E-钙粘素和白蛋白表达高,整合素和alpha-平滑肌动蛋白的表达水平较低,加药组与对照组变化趋势一致;30 kPa基底膜上细胞运动变形欠活跃,加药组与对照组相比,E-钙粘素和白蛋白表达均下调,alpha-平滑肌动蛋白表达上调;30 kPa与3.6 kPa对照组相比、30 kPa与3.6 kPa加药组相比,E-钙粘素及白蛋白表达均下调(P<0.05),alpha-平滑肌肌动蛋白的表达上调(P<0.05)。10 kPa基底膜上对照组和加药组与30 kPa和3.6 kPa对照组和加药组相比,均无显著性差异。结论基底硬度增加可诱导肝细胞表型转化,并促进TGF-β1对肝细胞代谢行为的影响。     

整合素分布变化与肝癌细胞迁移取向调节的相关性

目的采用机械拉伸方法并通过裱衬纤连蛋白(胞外基质成份)调节整合素受配体结合,探索整合素再分布变化对肝癌细胞黏附运动行为的影响,以及骨架重排对整合素再分布变化的影响。方法运用免疫荧光染色、激光共聚焦显微技术和定量形态学分析法,观察整合素分布变化和细胞骨架装配调整,及对细胞运动变形能力进行检测和定量分析。结果 (1)不同形态细胞的整合素表达和分布特征不同,铺展细胞β1整合素表达高于未铺展的圆细胞,分布峰值为基底面,而圆细胞游离面的整合素分布反较基底面多。(2)机械拉伸5h后不同形态细胞β1整合素表达均升高,分布带增宽;卸载1h整合素表达下调,出现弥散分布倾向,其中以圆细胞最为明显。(3)裱衬FN后β1整合素表达增加,不同形态细胞整合素分布均向基底转移,并使肝癌细胞净迁移距离减小。(4)机械拉伸5h后60%的细胞长轴取向集中在70°～110°之间,细胞骨架倾向垂直于拉伸方向排列,卸载1h细胞骨架明显解聚。结论肝癌细胞整合素分布变化受胞内骨架调整和胞外配体数量的影响,单个圆细胞的整合素分布特征与其较强的转移浸润能力相关。     

五味子乙素对肝癌细胞凋亡、侵袭及血管新生的调节作用

目的:本文旨在研究五味子乙素对肝癌细胞HCCLM3凋亡、侵袭及血管新生的影响。方法:MTT检测细胞存活力。流式细胞术分析细胞凋亡。Transwell检测细胞侵袭。蛋白印迹检测Bcl 2相关蛋白X(Bax)、B细胞淋巴瘤(Bcl-2)、基质金属蛋白酶2(MMP-2)、MMP-9、血管内皮细胞生长因子X(VEGF-A)、表皮生长因子(EGF)和成纤维细胞生长因子(b FGF)表达。结果:低浓度(20μmol/L)五味子乙素对HCCLM3细胞存活力无明显影响。高浓度(20μmol/L)五味子乙素会降低细胞存活力。与DMSO组相比,五味子乙素(10和20μmol/L)组细胞凋亡率明显升高,Bax表达增强,Bcl-2表达降低(P0. 05)。而且,五味子乙素(5、10、20μmol/L)组细胞侵袭及MMP-2和MMP-9表达明显低于DMSO组(P0. 05)。与DMSO组相比,五味子乙素(5、10、20μmol/L)组VEGF-A,EGF和b FGF表达明显下降(P0. 05)。结论:五味子乙素可诱导肝癌细胞HCCLM3凋亡,降低细胞侵袭及血管新生。     

CD133和CD34在肝细胞癌血管生成拟态形成中的表达及意义

背景：在恶性肿瘤中血管生成拟态的形成过程与肿瘤干细胞有密切联系。 目的：分析肝癌干细胞标志物CD133和CD34在肝细胞癌血管生成拟态形成中的表达及意义。 方法：建立肝癌细胞HCC97H、SMMC7721和正常肝细胞L02三维培养体系,结合激光捕获显微切割技术分离形成血管生成拟态的肝癌细胞,分别利用RT-PCR和Western blot技术检测CD133和CD34表达水平。 结果与结论：三维培养条件下,肝癌细胞HCC97H细胞形成血管生成拟态,肝癌细胞SMMC7721以及正常肝细胞L02未形成血管生成拟态。形成血管生成拟态的肝癌细胞HCC97H中CD133、CD34在mRNA及蛋白表达水平上均高于未形成血管生成拟态的肝癌细胞SMMC7721和正常肝细胞L02(P < 0.05)。表明高侵袭性肝癌细胞在三维培养下形成血管生成拟态,而低侵袭性肝癌细胞及正常肝细胞不能形成血管生成拟态;肝癌细胞形成血管生成拟态的过程中与表达肝癌干细胞有关。     

miR-222通过调控BCL2L13基因促进HBx-HepG2细胞生长

目的:探讨HBx-Hep G2细胞中微小RNA-222(mi R-222)对BCL2L13基因表达的调控作用以及对细胞生长和凋亡的影响,并研究其潜在的分子作用机制。方法:利用实时荧光定量PCR检测mi R-222的表达水平;MTT和集落形成实验检测细胞的生长;流式细胞术检测细胞周期和凋亡;构建BCL2L13 3’UTR双萤光素酶报告载体,通过采用双萤光素酶报告实验验证mi R-222的靶基因。结果:与正常的肝细胞L02相比,mi R-222在HBx-Hep G2细胞过量表达(P0.05)。mi R-222过表达可促进HBx-Hep G2细胞的生长,改变细胞周期,降低细胞的凋亡率;mi R-222表达下调可抑制HBx-Hep G2细胞的生长,改变细胞周期,增加细胞的凋亡率,和对照组相比差异有统计学显著性(P0.05)。与正常肝细胞L02相比,BCL2L13在HBx-Hep G2细胞表达下调(P0.05);mi R-222表达下调可促进BCL2L13的表达(P0.05)。双萤光素酶报告实验和pc DNA3.1-BCL2L13转染实验结果提示mi R-222可以通过作用于BCL2L13的3’UTR区,负向调控其表达,从而促进细胞的生长。结论:mi R-222可以通过靶向调控BCL2L13基因进而促进HBx-HepG2细胞的生长。     

Immunoregulatory function of mesenchymal stem cells

Mesenchymal stem cells (MSC) are a rare subset of stem cells residing in the bone marrow where they closely interact with hematopoietic stem cells and support their growth and differentiation. MSC can differentiate into multiple mesenchymal and non-mesenchymal lineages, providing a promising tool for tissue repair. In addition, MSC suppress many T cell, B cell and NK cell functions and may affect also dendritic cell activities. Due to their limited immunogenicity, MSC are poorly recognized by HLA-incompatible hosts. Based on these unique properties, MSC are currently under investigation for their possible use to treat immuno-mediated diseases. However, both their condition of immunoprivilege and their immunosuppressive function have recently been challenged when analyzed under particular experimental conditions. Thus, it is likely that MSC effects on the immune system may be deeply influenced not only by cell-to-cell interactions, but also by environmental factors shaping their phenotype and functions.     

Influences of the pia mater on the precursors of nerve cells

Summary In the developing cerebellum of 8-day old rats surgical lesions were made. During regeneration of the cerebellum the pia mater was found to penetrate inside the neural tissue. Partially differentiated Purkinje cells and granule cells, that were in close contact with the pial cells, were found atrophied. When the profilerative cells of external granular layer came into contact with the pial cells, they were reduced to a primitive type of epitheloid cells. In this instance epithelio-mesenchymal interaction was found deleterious to the precursors of neurons. However, when the epithelioid cells were freed from the contact with the pial cells by intervening basement membrane, they differentiated into ependymal cells. Such ependymal cells gave rise to small as well as large new ventriculer structures, and structures resembling chorioid plexus.This research was supported by NIH Research Grant NS08817-03. Acknowledgements are due to Sheila Anderson for histology and to Donna Whitehurst for photographic work.     

干细胞若干定义的相关探讨

背景：近10年来干细胞研究所取得的巨大进展,不仅影响和促进了生物学及其相关基础科学,而且还在医学、药物开发、农业等许多领域得到广泛的应用,目前已成为研究的热点问题。 目的：在干细胞的定义上还存在一些需要探讨的问题,明确定义将有利于干细胞研究的快速发展。 方法：回顾干细胞的发展和概念提出,特别是通过中英文权威定义的比较,提出作者的看法。 结果与结论：干细胞的定义上还存在一些问题值得探讨,特别是一些中英文表述不同影响了理解。例如,“多能干细胞”对应译成两个单词：Pluripotent Stem Cell和Multipotent Stem Cell,然而Pluripotent和Multipotent两个单词的英文意义不同。为了学术交流和沟通,作者提出将Pluripotent Stem Cell称为“万能干细胞”,而保留Multipotent Stem Cell为“多能干细胞”的定义。以上结论供广大同仁探讨,以利于抛砖引玉。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：     

Genetic aspects of the immunomodulationg action of interferon

Laboratory of Antiviral Immunity, N. F. Gamaleya Institute of Epidemiology and Microbiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR V. D. Solov'ev.) Translated from Byulleten' Éksperimentl'noioi Biologii i Meditsiny, Vol. 105, No. 4, pp. 459–461, April, 1988.     

Identification of a CD8α Dendritic Cell Subpopulation in Rat Spleen and Evaluation of Its OX-62 Expression

Rat spleen DC and bone marrow-derived DC were isolated and characterized by morphology and flow cytometry. We found a CD8α⁺ DC subpopulation representing 19–48% (27.4 ± 12.0) of total spleen DC. The OX-62 expression on total spleen DC was 41–59% (51.8 ± 7.5). Myeloid bone marrow-derived DC were negative for CD8α and OX-62. We demonstrated the coexpression of CD8α and OX-62 molecules, at least in a portion CD8α⁺ spleen DC. Both CD8α⁺ and CD8α⁻ spleen DC subpopulations separated by MACS were able to induce an in vivo primary immune response to OVA. The immune response induced by the CD8α⁻ DC subpopulation was higher (P < 0.05). We identified a CD8α⁺ DC subpopulation in rat spleen less effective in inducing an immune response than CD8α⁻ DC. Moreover, our results suggest the presence of DC subpopulations with different lineages in DC preparations based on OX-62 expression.     

Accessory phenotype and function of macrophages induced by cyclic adenosine monophosphate

Mature macrophages (Mph) differentiated in culture from normal human peripheral blood monocytes (Mo) exhibit low activity as accessory cells (antigen-presenting cells) in T lymphocyte stimulation. A test system was established based on mitogenicity to quantitate the accessory activity of Mph-derived cells and to follow its changes for several days. The system used accessory cells treated with the oxidative mitogen, sodium periodate. The cells were subsequently co-cultured with pooled human lymphocytes from a cryopreserved stock. DNA synthesis in these cells was used as an indicator of accessory activity. Mph could be converted within 5-6 days into highly active accessory cells if a continuous stimulus of exogenously added dibutyryl cyclic AMP (db-cAMP) was provided. Mph treated by db-cAMP retained a high degree of HLA-DR expression but typical Mph markers such as non-specific esterase, phagocytosis, and expression of Fc-receptors were down-regulated. Acid phosphatase and myeloperoxidase underwent only slight changes, while the monocyte marker 5'-nucleotidase remained undetectable. Morphologically, the cells rounded up and developed veils and dendritiform elongations. In contrast to dendritic cells, Mph-derived accessory cells retained the CD14 antigen characteristic of monocytes and Mph. It is concluded that Mph are able to respond to exogenous stimuli and to convert into a highly active accessory cell. This contrasts to the well-known state of the 'activated Mph' with respect to markers and function. Both states appear to be antagonistically controlled by intracellular second messengers, as the accessory cell phenotype is positively correlated with intracellular cyclic AMP increase, whereas Mph activation correlates with cyclic GMP increase.     

Human Osteogenic Sarcoma: Fine Structure of the Osteoblastic Type

The fine structure of representative regions of 13 osteoblastic osteogenic sarcomas was studied. These regions contained four morphologically distinguishable subtypes of osteoblastlike cells. In addition, fibroblastlike and chondroblastlike cells were present, along with multinucleated giant cells, leukocytes, macrophagelike cells, and small populations of histogenetically unclassifiable (but probably neoplastic) cells.

The morphologic evidence was compatible with the view that the variations in appearance among the subgroups of osteobl astlike cells reflected differences in maturation and differentiation of these cells. In at least one subgroup, the morphologic findings suggested that the ceils were capable of manufacturing a secretory product. The multinucleated giant cells occurring in genuine tumor areas appeared to be closely related to neoplastic osteoblasts.

The presence of chondroblastlike cells in the tissues illustrates that cells with a diverging differentiation can occur in an osteoblast-dominated cell population. This agrees with the view that the neoplastic cells originate from a mesenchymal stem cell with potential for multifaceted differentiation.     

Trypanosoma cruzi calreticulin: In vitro modulation of key immunogenic markers of both canine tumors and relevant immune competent cells

Recombinant calreticulin from Trypanosoma cruzi (rTcCalr), the parasite responsible for Chagas’ disease, binds to Canine Transmissible Venereal Tumor (CTVT) cells from primary cultures and to a canine mammary carcinoma cell line. A Complement-binding assay indicated that interaction of the first component C1q with these tumor cells operated independently of the rTcCalr-presence. This apparent independence could be explained by the important structural similarities that exist among rTcCarl, endogenous normal canine and/or mutated calreticulins present in several types of cancer. In phagocytosis assays, tumor cells treated with rTcCalr were readily engulfed by macrophages and, co-cultured with DCs, accelerated their maturation. In addition, DCs maturation, induced by tumor cells co-cultured with rTcCalr, activated T cells more efficiently than DCs, treated or not with LPS. In an apparent paradox, a decrease in MHC Class I expression was observed when these tumor cells were co-cultivated with rTcCalr. This decrease may be related to a down regulation signaling promoting the rescue of MHC I. Possibly, these in vitro assays may be valid correlates of in vivo sceneries. Based on these results, we propose that rTcCalr improves in vitro the immunogenicity of two widely different tumor cell lines, thus suggesting that the interesting properties of rTcCalr to boost immune responses warrant future studies.     

雪峰虫草对DC-CIK增殖及HepG-2细胞杀伤作用的实验研究

目的:研究雪峰虫草对DC-CIK细胞增殖及肝癌Hep G-2细胞杀伤作用。方法:常规分离健康人外周血单个核细胞并诱导生成DC细胞和CIK细胞,将DC细胞与CIK细胞按1∶5共培养7 d后给药组加入不同浓度的雪峰虫草水提取物,第10天观察形态并计数各组DC-CIK细胞;收集培养第10天的DC-CIK细胞作为效应细胞,对数生长期Hep G-2肝癌细胞作为靶细胞,使Hep G-2∶DC-CIK靶效比为1∶5,cck-8法检测DC-CIK对Hep G-2的杀伤率。结果:雪峰虫草水提物组对DC-CIK有显著的促增长作用,其作用的最佳浓度为0.1 mg/ml。雪峰虫草诱导的DC-CIK细胞对肝癌Hep G-2细胞的杀伤作用优于常规方法培养的DC-CIK细胞;常规方法培养的DC-CIK细胞加雪峰虫草与常规方法培养的DC-CIK细胞对肝癌Hep G-2细胞的杀伤作用无显著性差异,雪峰虫草体外直接杀伤肝癌Hep G-2细胞的作用不明显。结论:雪峰虫草通过促进DC-CIK细胞增殖而增强其杀伤肝癌Hep G-2细胞的作用。