假基因RPL34-PS1促进B细胞淋巴瘤生长的研究

通过将假基因RPL34-PS1的序列克隆至MSCV-PIG载体上后,包装反转录病毒并感染小鼠B淋巴瘤细胞38B9,构建稳定过表达RPL34-PS1的38B9细胞系.对体外培养的细胞进行计数观察细胞增殖;利用流式检测技术观察细胞的凋亡和周期;进行小鼠皮下荷瘤试验观察体内成瘤并进行相关机制研究.结果 表明:假基因RPL34-PS1对体外培养的38B9的生长速率、周期及凋亡无显著影响,但在体内能显著增加B细胞淋巴瘤的生长,其促进体内肿瘤生长的机制可能是肿瘤微环境中T淋巴细胞数量的减少之故,说明RPL34-PS1在微环境中靶向免疫细胞以促进肿瘤生长,RPL34-PS1可能可作为B细胞淋巴瘤的临床治疗的一个潜在靶点.     

弥罗松酚对B细胞淋巴瘤细胞株的作用研究

弥罗松酚梯度处理小鼠淋巴瘤细胞系38B9细胞后,采用CCK-8法测定细胞增殖活性;流式细胞术检测淋巴瘤细胞的凋亡率; Western blot检测Beclin1蛋白水平。建立B淋巴瘤小鼠模型并腹腔注射弥罗松酚,检测其对小鼠淋巴瘤的生长、凋亡的影响。结果表明:弥罗松酚对小鼠淋巴瘤细胞系38B9的生长有明显的抑制作用,且能显著促进细胞凋亡;弥罗松酚处理后, 38B9细胞Beclin1蛋白水平显著升高。这一研究提示弥罗松酚可显著抑制淋巴瘤的生长,同时诱导38B9细胞的凋亡,可能与弥罗松酚调控38B9细胞的自噬功能有关。     

IL-35+调节性B细胞在桥本甲状腺炎免疫发病机制中的作用

目的 探讨IL-35+调节性B细胞(i35-Breg)在桥本甲状腺炎(HT)免疫发病机制中的作用.方法 采用流式细胞术检测36例HT患者及32例对照者外周血CD 19+IL-12p35+IL-27EBI3+细胞比例及PD-L1、CD169、PD-1、CD43、IL-12p35、IL-27EBI3、IL-12Rp2、IL-27Rα、pSTAT1、pSTAT3蛋白表达水平,实时荧光定量PCR检测CD19+细胞SHP-2、Vav mRNA表达,ELISA检测血浆中IL-35、TNF-α、IL-12水平.结果 HT患者外周血CD 19+IL-12p35+IL-27EBI3+细胞比例及IL-12p35、IL-27EBI3、IL-10表达明显低于对照组(P＜0.01).HT患者血浆IL-35水平及CD19+B细胞IL-12Rβ2、IL-27Rα、pSTAT1、pSTAT3表达明显低于对照组(P＜0.01),而血浆TNF-α、IL-12水平及CD14+细胞PD-L1、CD169表达明显高于对照组(P＜0.01).结论 i35-Breg细胞数量及功能异常可能是导致HT患者免疫功能紊乱的重要因素之一.     

WWOX促进弥漫性大B淋巴瘤增殖作用初探

为研究WWOX在人弥漫性大B淋巴瘤(DLBCL)中的作用,首先对TCGA数据库中人WWOX (hWWOX)在DLBCL样本中的表达进行分析;随后在B细胞淋巴瘤细胞株Romas、OCI-Ly7(Ly7)、38B9及临床组织样本中对上述生物信息学分析结果进行验证;通过构建稳定过表达hWWOX的淋巴瘤细胞系进一步分析hWWOX过表达对DLBCL细胞增殖的影响;最后对该细胞内Jak2-Stat3通路的活化水平进行探究。结果表明：TCGA数据库DLBCL中hWWOX高表达并在B细胞淋巴瘤细胞株中得到验证;IHC结果显示,53%的DLBCL患者组织中hWWOX高表达。Western blot结果显示,过表达hWWOX的细胞系Ly7-hWWOX得到成功构建,MTT试验表明该稳转细胞株的增殖能力较对照组显著增强,且细胞中p-Jak2、p-Stat3水平显著上调。综上,hWWOX在DLBCL中主要通过上调Jak2-Stat3信号通路而促进癌细胞增殖,这为DLBCL的临床研究和治疗提供靶标。     

奶牛淋巴白血病中细胞凋亡与细胞增殖病理研究

利用细胞凋亡试剂盒（POD）及小鼠抗大鼠增殖细胞核抗原（PCNA）单克隆抗体将淋巴白血病中的凋亡细胞与增殖细胞准确地染色显示出来,并进行对比观察分析.结果表明,奶牛淋巴白血病中有凋亡细胞与增殖细胞,细胞凋亡与细胞周期调控是肿瘤发生发展的两方面.单克隆抗体免疫细胞化学方法可以很好地检测PCNA和细胞凋亡的表达,PCNA与细胞凋亡可作为奶牛淋巴白血病细胞增殖活性的指标,其表达可能是急性白血病预后不良的一个指标.可以认为牛淋巴白血病乃是细胞死亡被抑制,而细胞的增殖率相对升高的病理过程.     

B细胞活化因子及调节性T细胞在免疫性血小板减少症发病中的作用

目的 了解B细胞活化因子(BAFF)及调节性T(Treg)细胞在免疫性血小板减少症(ITP)发病中的作用.方法 采集34例ITP及28例健康对照者外周血,用流式细胞术检测外周血Treg细胞数,ELISA检测血浆BAFF水平.结果 ITP患者外周血Treg细胞/CD4+细胞比值低于对照者[(1.55±1.13)％ vs (2.73±0.83)％,P＜0.01],而血浆BAFF水平高于对照者[(1 426.14±1 280.67) μg/L vs (644.29±307.97) μg/L,P＜0.01].结论 BAFF与Treg细胞可能存在相互作用,从而参与ITP发病.     

低浓度紫杉醇诱导A549细胞凋亡研究

采用0、1．5、3、6nmol／L紫杉醇处理A549细胞,建立低浓度紫杉醇诱导非小细胞肺癌凋亡模型．分别采用流式细胞术、细胞计数和免疫印迹法分析细胞凋亡、细胞增殖和Bcl-2家族凋亡相关分子的表达。结果表明,低浓度紫杉醇以浓度和时间依赖的方式诱导细胞凋亡并上调Bim分子表达,而对Bcl-2家族其他凋亡相关分子无显著影响。     

细胞松弛素H对MPP~+诱导PC12细胞凋亡的保护作用

以500μmol·L-1甲基苯基吡啶离子(MPP+)制备帕金森病(PD)细胞模型,MTT法测定细胞存活率,比色法测定LDH释放量;AO/EB染色法、透射电镜法观察细胞凋亡形态;流式细胞仪分析细胞凋亡比率并测定ROS含量,探讨青皮内生菌(Phomopsis sp.)固体发酵产物细胞松弛素H(CyH)对MPP+诱导的PC12细胞凋亡的保护作用。结果表明:①CyH与MPP+同时加药(0.05~0.20μmol·L-1)、先加药(0.002 5~0.010 0μmol·L-1)和后加药(0.01~0.20μmol·L-1)均能使PC12细胞存活率显著增加,LDH释放率显著下降;②流式细胞仪测定表明CyH能够降低MPP+诱导的PC12细胞凋亡率(P0.001);透射电镜和AO/EB染色也显示细胞形态的改善;③CyH能显著抑制MPP+升高ROS含量的作用(P0.05)。说明CyH能抑制MPP+诱导的PC12细胞损伤和凋亡,这可能与其减少细胞内ROS含量有关。     

线粒体凋亡途径在硫酸黏菌素致PC12细胞凋亡中的作用

探讨线粒体凋亡途径在硫酸黏菌素诱导PC12细胞凋亡中作用.取对数生长期PC12细胞,用含0、62.5、125、250 μg· mL-1硫酸黏菌素DMEM培养液,作用24 h,采用Hoechst33258荧光染色法检测PC12细胞凋亡,Western blot法检测细胞色素C(Cyt-C)、Bax、Bcl-2蛋白表达含量,试剂盒检测Caspase-3活性.与对照组相比,125、250 μg· mL-1硫酸黏菌素剂量组细胞PC12细胞Cyt-C、Bax蛋白表达量、Caspase-3活性显著升高(P＜0.01);Bcl-2蛋白表达显著降低(P＜0.01),具有剂量-效应关系.说明线粒体途径介导PC12细胞凋亡是硫酸黏菌素神经毒性作用机制之一.     

Confirmation of Earth-Mass Planets Orbiting the Millisecond Pulsar PSR B1257 + 12

The discovery of two Earth-mass planets orbiting an old ( approximately 10(9) years), rapidly spinning neutron star, the 6.2-millisecond radio pulsar PSR B1257+12, was announced in early 1992. It was soon pointed out that the approximately 3:2 ratio of the planets' orbital periods should lead to accurately predictable and possibly measurable gravitational perturbations of their orbits. The unambiguous detection of this effect, after 3 years of systematic timing observations of PSR B1257+12 with the 305-meter Arecibo radiotelescope, as well as the discovery of another, moon-mass object in orbit around the pulsar, constitutes irrefutable evidence that the first planetary system around a star other than the sun has been identified.     

Rheumatoid factor secretion from human Leu-1+ B cells

A human B cell subpopulation identifiable by the expression of the cell surface antigen Leu-1 (CD5) is responsible for most of the immunoglobulin M rheumatoid factor secreted in vitro after the cells are stimulated with Staphylococcus aureus. The ability of B cells bearing the Leu-1 marker (Leu-1+) to secrete rheumatoid factor is present early in development and extends to adulthood, since Leu-1+ B cells from cord blood and from peripheral blood lymphocytes of both normal adults and patients with certain autoimmune conditions secrete rheumatoid factor in comparable amounts. The neonatal enrichment of Leu-1+ B cells, the presence of Leu-1+ B cells in increased frequencies in patients with autoimmune disease, and the involvement of Leu-1+ B cells in autoantibody secretion suggest both developmental and functional homologies between this human B cell subpopulation and the murine Ly-1 B cell subpopulation.     

Defect in vitamin B12 release from lysosomes: newly described inborn error of vitamin B12 metabolism

Cultured diploid fibroblasts from a patient with a previously undescribed inborn error of cobalamin metabolism accumulate unmetabolized, nonprotein-bound vitamin B12 in lysosomes. These cells are able to endocytose the transcobalamin II-B12 complex and to release B12 from transcobalamin II. The freed vitamin B12 is not released from lysosomes into the cytoplasm of the cell. This suggests that there is a specific lysosomal transport mechanism for vitamin B12 in the human.     

Methylmalonate excretion in vitamin B12 deficiency

Urinary methylmalonate excretion is increased in rats with an insufficiency of vitamin B(12). Excretion of methylmalonate is not affected by folic acid, vitamin E, or selenium, but is markedly decreased by small amounts of vitamin B(12) added to the diet.     

Production of immunoglobulin isotypes by Ly-1+ B cells in viable motheaten and normal mice

Almost all B cells in autoimmune mice with the viable motheaten (mev) mutation express the Ly-1 cell surface antigen, which marks a minor population of B cells constituting a separate lineage in normal mice. Immunoglobulins primarily of the M and G3 classes, which in both normal and mev mice contain high levels of lambda light chain, are produced in excess in mev mice. These and other observations suggest that the development of B cells that express Ly-1 is regulated independently from the development of B cells that do not express Ly-1. B cells bearing the Ly-1 surface antigen may play specialized roles in the normal immune system and in autoimmunity by regulating other B cells via lymphokines, by producing antibodies to self and certain foreign antigens, and by preferentially secreting immunoglobulin M and immunoglobulin G3.