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小神经球传代法扩充干细胞哈尔滨医科大学神经外科梁鹏博士在国家自然科学基金的支持下,利用小神经球传代方法建立了神经干细胞体外长期培养传代系统。用小神经球传代方法在体外可培养神经干细胞达到10个月,传代25代,从单一的细胞可扩增至10万个细胞。多次传代后细胞冻存对细胞的     

猫爪草多糖对小鼠腹腔巨噬细胞活力的调节作用

此次研究旨在探讨猫爪草多糖对体外培养的正常状态下的原代小鼠腹腔巨噬细胞活性的调节作用,以及小鼠腹腔巨噬细胞在体外培养条件下的活力变化情况。以原代培养的小鼠腹腔巨噬细胞为研究对象,设对照组(加入100μL DMEM培养基)和实验组(分别加入25μg/mL, 50μg/mL, 100μg/mL, 200μg/mL,400μg/mL的猫爪草多糖),分别采用噻唑蓝(MTT)比色法、CCK-8法、乳酸脱氢酶释放法和中性红吞噬实验检测不同浓度的猫爪草多糖对体外培养的小鼠腹腔巨噬细胞活力的调节作用;同时设置24 h、36 h、48 h、60 h和72 h的不同培养时间,观察在体外培养条件下,小鼠腹腔巨噬细胞活力的变化情况。结果表明:与对照组相比,不同浓度的猫爪草多糖均能增强小鼠腹腔巨噬细胞的活力,且猫爪草多糖浓度在100~400μg/mL的细胞活力极显著增强(p<0.01)。此外,各处理组的巨噬细胞在体外培养24~72 h不更换培养液的条件下,48 h处活性最佳。体外培养条件下,一定浓度的猫爪草多糖可以激活小鼠腹腔巨噬细胞,通过猫爪草多糖激活巨噬细胞,可能是猫爪草发挥提升机体免疫力的作用机制之一。此外,体外培养的巨噬细胞虽能存活长达一个月,但仍有一个最佳活力时间。     

大鼠脑神经干细胞系(RNSC-FMU 1)的建立和鉴定

采用无血清培养液分离和培养新生SD 大鼠脑的神经干细胞,以机械分散的方法传代,成功地建立了大鼠脑神经干细胞系(RSNC-FMU 1)。该细胞系可在体外长期传代,至今已在体外连续生长超过21个月(>100代),保持了神经干细胞的特性和正常的核型,经诱导可分化成为神经元、星形胶质细胞和少突胶质细胞,具有较旺盛的自新能力,倍增时间约为20h,并可冷冻保存,裸鼠体内移植证实其不具有成瘤性。该细胞系为神经干细胞研究提供了一个良好的工具。     

鰤诺卡氏菌对大口黑鲈头肾巨噬细胞的侵染过程

【背景】鱼类诺卡氏菌病潜伏期和病程较长,感染率和死亡率较高,给水产养殖业带来较大的经济损失,其病原鰤诺卡氏菌(Nocardia seriolae)是胞内寄生菌,侵入细胞后引起慢性感染是主要的致病机制。【目的】构建鰤诺卡氏菌侵染大口黑鲈(Micropterus salmoides)头肾巨噬细胞体外模型,观察鰤诺卡氏菌侵染巨噬细胞的过程并探究鰤诺卡氏菌对巨噬细胞的凋亡作用。【方法】采用密度梯度离心法分离巨噬细胞,通过特异性染色和PCR扩增巨噬细胞表达基因mpeg1对细胞进行鉴定,并通过CCK-8法和氧呼吸暴发活性测定检测巨噬细胞的活性;通过倒置荧光显微镜和流式细胞术观察侵染过程中细菌与细胞的形态与数量变化;通过双荧光流式细胞术检测、乳酸脱氢酶(lactate dehydrogenase, LDH)释放试验及线粒体膜电位检测,探究鰤诺卡氏菌对巨噬细胞的凋亡作用。【结果】从大口黑鲈头肾分离获得纯度高的巨噬细胞,经染色和PCR法鉴定为巨噬细胞;筛选出最优的体外培养条件为1640培养基+1%青霉素链霉素+1%胎牛血清。在脂多糖刺激后,巨噬细胞的氧呼吸暴发能力显著提高(P<0.05)。GFP-鰤诺卡氏菌侵染细胞2 h后细菌被细胞吞噬,4 h细胞变圆且贴壁率降低,6 h细菌大量繁殖并包围细胞,8 h后细胞大量死亡。凋亡相关实验结果表明,侵染初期巨噬细胞凋亡率增加,LDH释放增加,线粒体膜电位下降;随着侵染时间延长,细胞凋亡率下降、LDH释放量及线粒体膜电位下降减少,说明鰤诺卡氏菌对巨噬细胞起先促进后抑制凋亡的作用。【结论】通过密度梯度离心法成功分离大口黑鲈头肾巨噬细胞,并通过鰤诺卡氏菌侵染细胞后初步摸清鰤诺卡细菌在细胞水平的致病机理,建立了鰤诺卡氏菌侵染大口黑鲈头肾巨噬细胞的体外模型;证实了鰤诺卡氏菌可侵染巨噬细胞并抑制细胞凋亡,从而达到在巨噬细胞内存活,为进一步开展鰤诺卡氏菌与巨噬细胞相互作用并阐明鰤诺卡氏菌的致病机制奠定了研究基础。     

雪灵芝粗多糖对小鼠免疫细胞增殖与功能的体外激活作用

为观察雪灵芝粗多糖(Arenaria kansuensis crude polysaccharide,AKCP)对体外培养的小鼠脾淋巴细胞、NK细胞和腹腔巨噬细胞增殖与功能的影响。以不同浓度AKCP作用于体外培养的上述细胞48 h,采用中性红吞噬实验及NO释放实验检测巨噬细胞功能,MTT法检测脾淋巴细胞增殖及NK细胞杀伤活性,流式细胞术检测脾淋巴细胞CD3~+、CD4~+、CD8~+亚群,ELISA法检测脾细胞培养上清中IL-2和IFN-γ水平。结果显示,AKCP各浓度组小鼠腹腔巨噬细胞的吞噬活性和NO释放量、脾淋巴细胞刺激指数及培养上清中IFN-γ水平、NK细胞杀伤活性均高于空白对照组(P0.05);AKCP中浓度组脾淋巴细胞CD3~+、CD4~+亚群及培养上清中IL-2水平也明显升高(P0.05)。提示AKCP对小鼠免疫细胞的增殖与功能具有体外激活作用。     

小鼠腹腔激活巨噬细胞体外免疫调变机理的初步研究(简报)

激活巨噬细胞既是机体抵抗肿瘤和微生物感染的一类效应细胞,又是重要的免疫调节细胞。但是,激活巨噬细胞同时具有抗肿瘤作用和免疫抑制效应已被大量实验所证实。这种免疫抑制作用是肿瘤免疫治疗中亟待解决的一个问题。我们实验室近来的工作表明,用高剂量的脂多糖(LPS,10μg/ml)体外处理巯基乙醇酸钠诱发的小鼠腹腔巨噬细胞和培养的人体     

以支持细胞为饲养层培养小鼠精原干细胞

为探索精原干细胞(Spermatogonialstemcells,SSCs)体外自增殖的条件以及SSCs体外快速扩增的方法,以6-8日龄昆明乳鼠为材料,分离小鼠睾丸细胞,采用Percoll梯度离心法富集SSCs;以经丝裂霉素C处理的Sertoli细胞作饲养层,以DMEM为基本培养基,加入5%胎牛血清和103u/ml的白血病抑制因子(Leukemiainhibitoryfactor,LIF),体外培养SSCs;运用免疫荧光技术,以SSCs特异性表面分子Thy1为标志,对原代培养20d和传代培养14d的细胞进行鉴定。该培养体系下,SSCs贴壁时间为6h-9h,48h后可见细胞分裂,迅速增殖出现在接种12d以后。接种后第20d形成数十至上百个细胞的细胞团,细胞总数比接种时增加了45-245倍,100倍显微镜下观察可见,单位视野内细胞团数为26±4个。传代后细胞增殖较快。原代培养20d和传代培养14d的细胞均为Thy1阳性;而传代20d后,细胞周缘不整,有伪足出现,呈现出死亡迹象。该培养条比较适合SSCs短期快速增殖。     

人体膀胱移行细胞癌细胞系KGBC的建立及其生物学特性

本文报告建立了一株人膀胱移行细胞癌细胞系,命名为KGBC。KGBC细胞已在体外培养了10个月,传代65代。组织培养中,KGBC细胞形态为上皮样,呈单层或多层生长,接触抑制消失。光镜和电镜下,KGBC细胞的形态结构与膀胱移行细胞癌的形态结构相似。第27代和第42代细胞异种移植,能在小鼠体内生长,组织相与原发癌相似。第9代和第21代细胞的染色体数从65到190条,众数为90—95条。第35代细胞倍增时间为28小时。细胞经液氮保存,复苏良好。这些表明已建立了一株能在体外稳定生长的人膀胱癌细胞系。     

病毒学研究中常用的细胞系和细胞株一览表

<正> 病毒必须依赖宿主细胞的酶和代谢系统才能生存和进行复制。组织培养法由于其本身的许多优点已成为理想的病毒培养系统。组织培养技术的发展为病毒学提供了很好的工具和方法,它已广泛应用于病毒性疾病的诊断、疫苗生产、抗病毒药物的研究以及病毒学基础理论的研究,如病毒复制过程、病毒免疫和病毒生物化学等。 从培养类型来看,组织培养可分为组织块培养、原代细胞培养、次代细胞培养、传代细胞系、传代细胞株和器管培养等。     

巨噬细胞RNA合成的某些特点

在低浓度(≤1μg/ml)放线菌素D作用下,兔腹腔巨噬细胞RNA合成被抑制的情况与兔肾细胞类似。但随着放线菌素D浓度增高,反而促进巨噬细胞的RNA合成。在浓度为100μg/ml时,可使~3H-尿苷的掺入量比对照增加2—10倍。相反,在此浓度下,兔肾细胞的RNA合成却完全被抑制。蔗糖的存在能使巨噬细胞丧失对放线菌素D这种刺激作用反应的能力,其RNA合成完全被抑制。另一方面,巨噬细胞的KNA聚合酶对利福平的敏感性要比其他非免疫细胞至少高4—5倍。如果用高浓度的(500μg/ml)利福平完全抑制巨噬细胞的转录之后,再     

A stromal cell line from rainbow trout spleen, RTS34st, that supports the growth of rainbow trout macrophages and produces conditioned medium with mitogenic effects of leukocytes

Summary A rainbow trout spleen cell line, RTS34, was developed from a long-term hemopoietic culture. This cell line consisted of a mixed stromal cell layer with an associated cell population of macrophage-like cells that formed proliferative foci and released nonadherent progeny cells into the culture medium. A stromal cell line, RTS34st, was isolated from the RTS34 cell line. RTS34st cultures contained cells with fibroblast-like and epithelial-like morphologies and showed enhanced [³H]thymidine incorporation in response to either FBS or rainbow trout serum. The combination of FBS and trout serum was synergistic. Conditioned medium from RTS34st stimulated thymidine incorporation by peripheral blood and head kidney leukocytes, but not by leukocytes from the spleen. In addition, RTS34st provided a hemopoietic inductive microenvironment for immature precursor cells, selectively supporting the growth of macrophage-like cells. Therefore, RTS34st appears useful for studying the different roles of the stroma in regulating hemopoiesis in fish.     

Virulence and nucleotide sequence analysis of marine viral haemorrhagic septicaemia virus following in vivo passage in rainbow trout Onchorhynchus mykiss

A marine isolate of viral haemorrhagic septicaemia virus (VHSV) (860/94) was passaged in triplicate through sequential batches of rainbow trout via an intra-peritoneal infection route, without amplification in tissue culture. Following 5 passages, the VHSV glycoprotein gene was amplified directly from fish tissue homogenates and the consensus sequence compared to that of the original tissue culture isolate. Virus was also recovered directly from pools of kidney and spleen material after 5 passage events, and its virulence compared to that of unpassaged material by intra-peritoneal infection. Following passage in rainbow trout, isolate 860/94 exhibited a higher virulence for rainbow trout than unpassaged material. Sequence comparisons identified no difference in the consensus sequence of the glycoprotein gene following in vivo passage. The mechanisms responsible for the observed increase in virulence of isolate 860/94 following passage in rainbow trout thus remain unknown. The possibility that viral isolates may exhibit an increased virulence following passage in novel host species does, however, have important implications with regard to the epidemiology of this important fish pathogen.     

Proteome Profiles of Head Kidney and Spleen of Rainbow Trout (Oncorhynchus Mykiss)

The head kidney and spleen are major lymphoid organs of the teleost fish. The authors identify proteome profiles of head kidney and spleen of rainbow trout (Oncorhynchus mykiss) using a shotgun proteomic approach. Gene ontology annotation of proteins is predicted using bioinformatic tools. This study represents detailed proteome profiles of head kidney and spleen of rainbow trout, with a total of 3241 and 2542 proteins identified, respectively. It is found that lymphoid organs are equipped with a variety of functional proteins related to defense, receptor, signal transduction, antioxidant, cytoskeleton, transport, binding, and metabolic processes. The identified proteome profiles will serve as a template for understanding lymphoid organ functions in salmonids and will increase the amount of spectra information of rainbow trout proteins in the public data repository PRIDE. This data can be accessed via ProteomeXchange with identifiers PXD008473 and PXD008478.     

A putative beta2-adrenoceptor from the rainbow trout (Oncorhynuchus mykiss). Molecular characterization and pharmacology.

Extensive molecular characterization of mammalian beta-adrenoceptors has revealed complex modes of regulation and interaction. Relatively little attention, however, has focused on adrenoceptors from early branching vertebrates such as fish. Using an RT-PCR approach we have cloned a rainbow trout beta2-adrenoceptor gene that codes for a 409-amino-acid protein with the same seven transmembrane domain structure as its mammalian counterparts. This rainbow trout beta2-adrenoceptor shares a high degree of amino-acid sequence conservation with other vertebrate beta2-adrenoceptors. The conclusion that this sequence is a rainbow trout beta2-adrenoceptor is further supported by phylogenetic analysis of vertebrate beta-adrenoceptor sequences and competitive pharmacological binding data. RNase protection assays demonstrate that the rainbow trout beta2-adrenoceptor gene is highly expressed in the liver and red and white muscle, with lower levels of expression in the gills, heart, kidney and spleen of the rainbow trout. The lack of regulatory phosphorylation sites within the G-protein-binding domain of the rainbow trout beta2-adrenoceptor sequence suggests that the in vivo control of trout beta2-adrenoceptor signaling differs substantially from that of mammals.     

The population dynamics of eyeflukes Diplostomum spathaceum and Tylodelphys clavata (Digenea: Diplostomatidae) in rainbow and brown trout in Rutland Water: 1974–1978

The development of populations of eyeflukes Diplostomum spathaceum and Tylodelphys clavata in trout introduced into Rutland Water is related to the availability of infected Limnaea pereger, the first intermediate host, and the differential resistance to eyeflukes in Salmo gairdneri and S. trutta. The numbers of snail and fish intermediate hosts were monitored from impoundment of the Gwash in 1974 to completion of the reservoir in 1978. High infection rates in coarse fish in the feeder streams in 1974 are related to high infection rates in Limnaea pereger. Large eyefluke populations in introduced rainbow trout but not in brown trout confirm their differential resistance. Differences in levels of infection in seine-netted and rod-caught rainbow trout suggest that heavily infected fish could not respond to the fishermens' lures. Reduced numbers of eyeflukes in rainbow trout from 1979 onwards are related to the vast increase in volume of the reservoir in 1977 and decrease in abundance of Limnaea pereger.     

一例虹鳟低死亡率疾病的病原学及病理学研究

为确定病原类型和造成虹鳟低死亡率的原因,研究对患病虹鳟进行了病理学观察、病毒的分离和鉴定以及动物感染实验。临床检查发现发病虹鳟体色变黑,肌肉和腹壁点状出血。病理学观察发现虹鳟造血器官脾和肾间组织严重坏死。通过反转录PCR法检测坏死组织和病变细胞中传染性造血器官坏死病毒、出血性败血病毒和传染性胰腺坏死病毒,并对得到的371 bp大小片段进行测序和构建进化树分析,发现感染病原为传染性造血器官坏死病毒。同时,给体重为1.5 kg健康虹鳟腹腔注射104 TCID50的组织滤液,累计死亡率达到35%。除此之外,将组织滤液接种到鲤鱼上皮瘤细胞系后出现了特征性病变。在实验过程中未发现细菌或寄生虫感染。结果证实引起虹鳟低死亡率的病原为传染性造血器官坏死病毒。     

Effects of acute iron overload on Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss)

Distribution of radioiron to various tissues after intraperitoneal injections was examined in Atlantic salmon and rainbow trout. Liver and spleen were found to be the major iron storage tissues. Injections of 1 or 5 mg iron as ferric ammonium citrate led to a fall in hemoglobin levels in both species after 2 d. Hemoglobin levels returned to normal levels in rainbow trout after 8 d, but Atlantic salmon had not recovered, and Hb levels fell below 3 g/100 mL. In both species, the fall in Hb was associated with a raise in iron levels in spleen and liver, suggesting damage to erythrocytes. Atlantic salmon liver ferritin showed a two- to threefold increase, while rainbow trout showed a sixfold increase, and a more rapid response. The toxic effect of iron in fish appears to be different from the effect in other vertebrates.     

Ontogeny and disease responses of Langerhans-like cells in lymphoid tissues of salmonid fish

The ontogeny and disease responses of Langerhans-like cells within lymphoid tissues of Atlantic salmon, Salmo salar, and rainbow trout, Oncorhynchus mykiss, were investigated. These cells were studied in situ with the use of two markers: the ultrastructural presence of Birbeck-like granules and immunohistochemistry with an antibody against human langerin/CD207 that cross-reacts with salmonid tissues. The appearance of Birbeck-like granules was observed in rainbow trout at 2 weeks post-hatch (PH) in the thymus and anterior kidney prior to the development of the spleen. Spleen first appeared at 3 weeks PH in both Atlantic salmon and rainbow trout, and Birbeck-like granules were observed within cells of the newly developed spleens. The cross-reactivity of langerin as seen by immunohistochemistry was not clearly observed in kidney and spleen until 9 weeks PH, when a strong cytoplasmic reaction was observed. To study langerin-positive cells in spleen and kidney during disease, microsporidial gill disease (MGD) in rainbow trout was used as a known disease model inducing a strong cell-mediated adaptive immune response. Langerin-positive cells in healthy fish were seen predominantly in the spleen, and only low numbers were present in the anterior kidney. During MGD, langerin-positive cell numbers were elevated in the anterior kidney and were significantly higher during 5, 6, and 10 weeks post-exposure (PE) compared with healthy control tissue. During MGD, the distribution of langerin-positive cells in the spleen and anterior kidney shifted from having significantly higher numbers of cells in the spleen than in the kidney in controls and at 1 and 4 weeks PE to having a similar distribution of the cells in the two organs at 2, 3, 5, and 6 weeks PE. By 10 weeks PE, significantly higher numbers of langerin-positive cells occurred in the anterior kidney compared with the spleen.     

Rhabdovirus infection induces public and private T cell responses in teleost fish.

Many viruses induce a strong T cell response that contributes to the elimination of infected cells presenting viral peptides by MHC molecules. The structure and expression of genes encoding molecules homologous to mammalian alphabeta TCRs have been recently characterized in rainbow trout and in several teleost species, but the alphabeta T cell response against pathogens has not been directly demonstrated. To study the modifications of the T cell repertoire during an acute viral infection in rainbow trout, we adapted the immunoscope methodology, which consists of spectratyping the complementarity-determining region 3 length of the TCRbeta chain. We showed that the naive T cell repertoire is polyclonal and highly diverse in the naive rainbow trout. Using viral hemorrhagic septicemia virus (VHSV), which provokes an acute infection in rainbow trout, we identified skewed complementarity-determining region 3 size profiles for several VbetaJbeta combinations, corresponding to T cell clonal expansions during primary and secondary response to VHSV. Both public and private T cell expansions were shown by immunoscope analysis of spleen cells from several infected individuals of a rainbow trout clone sharing the same genetic background. The public response to VHSV consisted of expansion of Vbeta4Jbeta1 T cell, which appeared early during the primary response and was strongly boosted during the secondary response.