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991.
目的比较从人外周血单核细胞及脐血CD34+细胞诱导树突细胞(DC)的方法及其特性.方法用淋巴细胞分离液分离外周血单个核细胞,贴壁法获得单核细胞;经GM-CSF及IL-4诱导获得DC.磁性活化细胞分选系统(MACS)分选脐血CD34+细胞,以GM-CSF、IL-4、TNF-α、SCF、FL、TPO等细胞因子诱导获得DC.用电镜、普通显微镜观察DC形态;流式细胞仪分析DC表型;同种混合淋巴细胞反应(allo-MLR)观察DC刺激T淋巴细胞增殖的能力.结果外周血单核细胞在因子GM-CSF、IL-4、TNF-α,脐血CD34+细胞在GM-CSF、IL-4、TNF-α、SCF、FL、TPO等因子作用下,可生成DC,并表达相应的DC分化抗原CD14、CD80、CD83、CD86、HLA-DR.脐血CD34+细胞具有较强的扩增能力,经2周诱导,体系细胞数可增加173.8士26.7倍,两种来源的DC均能刺激同种异体淋巴细胞的增殖反应.结论外周血单核细胞与脐血CD34+细胞,在体外均可诱导成DC,并具有相应的DC分化抗原和功能. 相似文献
992.
目的:研究重组杆状病毒(baculovinus)载体介导β—半乳糖苷酶基因(LacZ)对体外培养虹膜色素上皮(IPE)细胞的转染和表达情况。方法:将质粒pCMV—β中的CMV—LacZ表达盒插入杆状病毒表达栽体pFast BacI的Eco RI/Hind Ⅲ位点,构建重组质粒pBac—β,并利用Bac—to—Bac表达系统在Sf9细胞中产生出重组杆状病毒BV—β。将MOI为200的BV—β感染经酶消化加显微法分离培养的IPE细胞,24h后进行X-gal染色。在显微镜下观察IPE中LacZ表达阳性的情况,记录阳性细胞所占的百分比。结果:限制性酶切分析及测序结果表明,我们已成功构建表达质粒pBac—β及重组杆状病毒BV—β。X-gal染色证实杆状病毒介导LacZ在细胞中的表达呈蓝色,弥漫于整个胞浆。感染后24h时表达阳性率达85%。结论:重组杆状病毒可有效介导报告基因在体外培养的IPE细胞中表达,为利用杆状病毒构建可供移植的基因工程化虹膜色素上皮细胞提供了实验依据。 相似文献
993.
目的 利用聚合酶链反应的酶联免疫吸附试验 ,探讨检测自排尿脱落细胞端粒酶活性在膀胱癌早期诊断中的意义。方法 应用 (端粒酶重复序列扩增基础上PCR -ELISA)TRAP -PCR -ELISA方法检测 5 8例膀胱癌患者、 2 5例良性血尿患者及 30例健康体检者尿脱落细胞的端粒酶活性。结果 (1) 5 8例膀胱癌患者尿脱落细胞阳性率为 81 0 % (4 7/ 5 8) ,2 5例良性血尿患者及健康体检者均无端粒酶活性表达。 (2 )TRAP -PCR -ELISA方法检测膀胱癌患者尿脱落细胞端粒酶活性与常规尿细胞形态学镜检间的差别有非常显著性意义 (P <0 0 1)。结论 尿脱落细胞端粒酶活性的检测法对膀胱癌患者的阳性检出率较常规尿细胞形态学方法高 ,可用于膀胱癌的早期诊断。 相似文献
994.
成骨细胞与血管内皮细胞联合培养的生物学特性 总被引:7,自引:1,他引:6
目的探讨成骨细胞与血管内皮细胞联合培养的生物学特性. 方法取2周龄乳兔颅盖骨及肾脏皮质传代培养制备成骨细胞(A组)、血管内皮细胞(B组)及成骨细胞与血管内皮细胞联合培养(C组),用Ⅰ型胶原和血管Ⅷ因子免疫细胞化学染色鉴定成骨细胞和血管内皮细胞,倒置相差显微镜和组织学染色观察细胞的生长特性和细胞相容性,检测碱性磷酸酶 (alkaline phosphatase,ALP)活性,观察血管内皮细胞对成骨细胞产生的ALP活性有无影响,MTT法检测细胞活力,分析细胞生长和增殖情况. 结果免疫细胞化学染色证实,培养的细胞为成骨细胞和血管内皮细胞.倒置相差显微镜、HE和Masson染色均显示两种细胞混合生长良好.ALP检测结果:C组ALP活性明显高于A组和B组(P<0.01),A组高于B组(P<0.05).MTT检测结果表明:C组细胞早期增殖较慢,而后期增殖较快. 结论成骨细胞与血管内皮细胞具有良好的相容性,血管内皮细胞能够增强成骨细胞的ALP活性,提高成骨细胞的增殖能力.联合培养细胞具有很强的增殖潜能. 相似文献
995.
The delayed cytotoxicity of the Multicentre Evaluation of In vitro Cytotoxicity (MEIC) reference chemicals was investigated in rat hepatoma-derived Fa32 cells. The cells were treated for 24 h with the test chemicals, and were than further cultured for 5 days in normal culture medium. The cytotoxicity was measured by the neutral red uptake inhibition, and the results were quantified by determining the NI50del. This is the concentration of test compound required to decrease the neutral red uptake with 50% compared with control cells. The results were compared with the acute NI50, the corresponding value measured immediately after 24 h treatment of the cells. On a total of 44 chemicals, nine showed delayed cytotoxicity (NI50del lower than or equal to NI50), 11 a probably delayed, and 24 no delayed cytotoxicity (NI50del more than 1.5×NI50). When the NI50del was compared with human toxicity, a correlation coefficient r2=0.761 was obtained. For the same series of 44 chemicals this correlation was clearly higher than that for human hepatoma-derived Hep G2 cells (r2=0.695). The Hep G2 assay was the best acute in vitro assay for the prediction of human toxicity within the MEIC study. Consequently, the delayed cytotoxicity assay on cultured Fa32 cells has the best prediction value so far obtained for the human toxicity. 相似文献
996.
聚—DL—乳酸复合材料的细胞毒性评价 总被引:2,自引:0,他引:2
孙皎 《口腔材料器械杂志》1998,7(2):66-67
本文对新研制的聚-DL-乳酸可吸收复合材料进行细胞毒性的实验研究,采用L-929小鼠成纤维细胞,经材料浸提液与细胞接触2、4、7 天后,在分光光度仪下测定光吸收度,以评价材料的细胞毒性.结果表明;该材料对培养细胞无明显细胞毒性刺激作用,细胞生长良好,各期实验组的细胞增殖状况与阴性对照组相似. 相似文献
997.
M. L. Kukushkin E. I. Danilova V. N. Grafova V. S. Smirnova V. K. Reshetnyak 《Bulletin of experimental biology and medicine》1998,125(5):457-460
Analgesic activity of a new anticonvulsive agent lamotrigin was studied on the model of neurogenic pain syndrome produced
in rats by penicillin applied to the dorsal surface of the spinal cord and by dissection of the sciatic nerve. Lamotrigin
was shown to have a profound analgesic activity. It can be used as an efficient prophylactic agent for prevention of chronic
pain syndromes by suppression of the generators of pathologically enhanced excitation in the nociceptive structures which
are the pathophysiological basis of the chronic pain syndromes.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 125, No. 5, pp. 517–521, January, 1998. 相似文献
998.
本文采用Griess试剂、间接免疫荧光法和同位素释放等方法,发现新城鸡瘟病毒Losota系(NDV-L)与人外周血粘附性单个核细胞(a-MCs)作用2~4h后,可稳定地吸附在a-PBMCs表面,并使其释放一氧化氮(NO),释放量与阳性对照组(BCG-LPS作用的a-PBMCs)相近;采用~3H-TdR释放法测定NDV-L作用的a-PBMCs对K_(562)靶细胞的细胞毒活性,发现具有明显的杀伤效应,且该杀伤效应与NO的产生有一定的依赖性。 相似文献
999.
Manfred Kopf Suzanne Herren Michael V. Wiles Mark B. Pepys Marie H. Kosco-Vilbois 《The Journal of experimental medicine》1998,188(10):1895-1906
Mice rendered deficient for interleukin (IL) 6 by gene targeting were evaluated for their response to T cell–dependent antigens. Antigen-specific immunoglobulin (Ig)M levels were unaffected whereas all IgG isotypes showed varying degrees of alteration. Germinal center reactions occurred but remained physically smaller in comparison to those in the wild-type mice. This concurred with the observations that molecules involved in initial signaling events leading to germinal center formation were not altered (e.g., B7.2, CD40 and tumor necrosis factor R1). T cell priming was not impaired nor was a gross imbalance of T helper cell (Th) 1 versus Th2 cytokines observed. However, B7.1 molecules, absent from wild-type counterparts, were detected on germinal center B cells isolated from the deficient mice suggesting a modification of costimulatory signaling. A second alteration involved impaired de novo synthesis of C3 both in serum and germinal center cells from IL-6–deficient mice. Indeed, C3 provided an essential stimulatory signal for wild-type germinal center cells as both monoclonal antibodies that interrupted C3-CD21 interactions and sheep anti–mouse C3 antibodies caused a significant decrease in antigen-specific antibody production. In addition, germinal center cells isolated from C3–deficient mice produced a similar defect in isotype production. Low density cells with dendritic morphology were the local source of IL-6 and not the germinal center lymphocytes. Adding IL-6 in vitro to IL-6–deficient germinal center cells stimulated cell cycle progression and increased levels of antibody production. These findings reveal that the germinal center produces and uses molecules of the innate immune system, evolutionarily pirating them in order to optimally generate high affinity antibody responses. 相似文献
1000.
The number of colony-forming cells (CFC) in the peripheral blood (PB) of 43 volunteers was examined using a semisolid clonogenic
culture assay. In all, 22 male (age 21–39 years) and 21 female individuals (age 21–39 years) were tested, ten of each group
twice to examine the intraindividual variability of colony-forming cells in PB. A statistically significant sex difference
in the number of CFC, erythroblastic colonies (BFU-E), and granulocyte/macrophage colonies (CFU-GM) in PB was detected in
favor of male individuals. No significant difference between female and male PB was found for the number of CFU-GEMM. The
intraindividual variability of CFC and BFU-E was significantly higher in female donors. These results support previous reports
by others on a potential influence of sex steroids on hematopoiesis.
Received: 8 November 1996 / Accepted: 4 April 1997 相似文献