Increased numbers of CD38 molecules on bright CD8+ T lymphocytes in infectious mononucleosis caused by Epstein-Barr virus infection

The aim of this study was to quantify the expression of CD38 on CD8+ T lymphocytes of patients with infectious mononucleosis (IM) caused by Epstein-Barr virus (EBV) and cytomegalovirus (CMV). CD38 quantification technique chosen for this study was based on the enumeration of CD38 antibody binding sites in comparison to the quantification standards rather than determining relative fluorescence, which is difficult to standardize. The study enrolled 19 patients with typical clinical and laboratory parameters compatible with EBV-induced IM as well as 10 patients with atypical clinical presentation of this disease. Furthermore, CD38 expression was analysed in a group of 13 patients with IM caused by CMV infection. CD38 quantification was performed within 6 days of the presentation of symptoms. All three groups of IM patients showed a statistically significant increase in the number of anti-CD38 antibody binding sites (which correspond to the number of CD38 molecules) on bright CD8+ T lymphocytes compared to healthy controls. The numbers of CD38 molecules expressed on CD8+ T lymphocytes did not differ significantly between IM patients with typical and atypical clinical presentation of the disease. Patients with CMV-induced IM had significantly lower numbers of CD38 molecules expressed on CD8+ T lymphocytes. Therefore, we conclude that CD38 quantification could be helpful in differential diagnostics of IM cases with atypical clinical presentation.     

Epstein-Barr virus and human immunodeficiency virus serological responses and viral burdens in HIV-infected patients treated with HAART

Epstein-Barr virus (EBV) associated non-Hodgkin lymphoma is recognized as a complication of human immunodeficiency virus (HIV) infection. Little is known regarding the influence of highly active antiretroviral therapy (HAART) on the biology of EBV in this population. To characterize the EBV- and HIV-specific serological responses together with EBV DNA levels in a cohort of HIV-infected adults treated with HAART, a study was conducted to compare EBV and HIV serologies and EBV DNA copy number (DNAemia) over a 12-month period after the commencement of HAART. All patients were seropositive for EBV at baseline. Approximately 50% of patients had detectable EBV DNA at baseline, and 27/30 had detectable EBV DNA at some point over the follow-up period of 1 year. Changes in EBV DNA copy number over time for any individual were unpredictable. Significant increases in the levels of Epstein-Barr nuclear antigen (EBNA) and Epstein-Barr early antigen (EA) antibodies were demonstrated in the 17 patients who had a good response to HAART. Of 29 patients with paired samples tested, four-fold or greater increases in titers were detected for EA in 12/29 (41%), for EBNA in 7/29 (24%), for VCA-IgG in 4/29 (14%); four-fold decreases in titers were detected in 2/29 (7%) for EA and 12/29 (41%) for EBNA. A significant decline in the titer of anti-HIV antibodies was also demonstrated. It was concluded that patients with advanced HIV infection who respond to HAART have an increase in their EBV specific antibodies and a decrease in their HIV-specific antibodies. For the cohort overall, there was a transient increase in EBV DNA levels that had declined by 12 months.     

EBV-encoded EBNA-5 associates with P14ARF in extranucleolar inclusions and prolongs the survival of P14ARF-expressing cells

Epstein-Barr virus (EBV) carrying lymphoblastoid cells of normal origin express the full program of all 9 virus-encoded, growth transformation associated proteins. They have an intact p53 pathway as a rule. This raises the question of whether any of the viral proteins impair the pathway functionally. Using a yeast 2-hybrid system, we have shown that EBNA-5 but not the other EBNAs interacts with the p14ARF protein, a regulator of the p53 pathway. The interaction was confirmed in vitro using a GST pull-down assay. Moreover, expression of EBNA-5 increased the survival of p14ARF-transfected cells. EBV infection of resting B cells induced the expression of p14ARF mRNA without increased level of the protein. A fraction of the p14ARF localized to the nucleoli but the bulk of the protein accumulated in nuclear but extranucleolar inclusions. Formation of the extranucleolar inclusions led to complete relocalization of EBNA-5 from nucleoplasm to these structures. The inclusions also contained p53 and HDM2, and were surrounded by PML bodies and proteasomes, which suggests that these inclusions could be targets for proteasome dependent protein degradation.     

抗重组EB病毒抗原双重抗体检测血清学诊断鼻咽癌的研究

背景与目的：在评估4种EB病毒抗原酶联免疫吸附法的基础上,探讨优化抗重组：EB病毒抗原双重抗体检测应用于血清学诊断鼻咽癌。方法：收集广州地区57例治疗前鼻咽癌患者和58例健康成人的血清。应用：EB病毒特异抗原(谷胱甘肽转移酶重组融合蛋白)为基础的4种免疫酶联吸附法,即：EBNA1-IgA,EBNA1-Igg,Zta-IgA和Zta-IgG检测血清中抗EB病毒的抗体水平。结果：EBNA1-IgA的灵敏度(O．9123)和阴性预测值(0．9074)是单独使用4种ELISA实验中最高的。Zta-IgA具有最高的正确率(π,0．8870)和Youden指数(J,0．7738)。当评估配对的ELISA时,EBNA1-IgA和Zta-IgA双重阳性的所有指标是4种双重阳性实验中最高的。5例：EBNA1-IgA阴性的鼻咽癌患者呈Zta-IgA阳性,而7例Zta-IgA阴性的鼻咽癌患者呈EBNA1-IgA阳性。结论：EBNA1-IgA酶联免疫吸附的单独检测在血清学诊断鼻咽癌时优于其他3项(EBNA1-IgG、Zta-IgA和Zta-IgG)单独酶联免疫吸附检测。EBNA1-IgA和Zta-IgA两项的组合应用在血清学诊断鼻咽癌时有互补作用,是血清学检测的合适组合。     

EBV-LMP1对鼻咽癌细胞系CNE1细胞转移相关因素的影响

背景与目的:已证实EB病毒(Epstein-Barrvirus,EBV)编码的潜伏膜蛋白1(latentmembraneprotein1,LMP1)能够诱导鼻咽癌细胞中基质金属蛋白酶9(matrixmetalloproteinase-9,MMP-9)的表达。本实验的目的是观察EB病毒潜伏膜蛋白1(EBV-LMP1)对鼻咽癌细胞系CNE1细胞转移相关因素的影响,探讨LMP1在鼻咽癌侵袭、转移过程中的作用。方法:用免疫组化法及Westernblot法检测CNE1-GL(转染LMP1基因的CNE1细胞)和CNE1细胞中MMP-9的表达情况;用细胞-基质粘附实验、细胞运动实验和肿瘤细胞重组基底膜侵袭实验检测LMP1对CNE1细胞粘附、运动及侵袭能力的影响。结果:免疫组化法及Westernblot法结果均显示CNE1-GL细胞中MMP-9的表达明显高于CNE1细胞(P<0.05);肿瘤细胞-基质粘附实验结果显示,CNE1-GL的粘附能力(平均吸光度值为1.2508±0.0711),高于CNE1细胞(平均吸光度值为0.9519±0.068),两者相比差异有显著性(P<0.01)。运动实验及重组基底膜侵袭实验结果均显示,穿过游离的聚乙烯吡咯烷酮膜(polyvinylpyrroli-done-free,PVP-F)的CNE1-GL细胞数明显高于CNE1细胞(P<0.01)。结论:LMP1能够诱导CNE1细胞中MMP-9的表达,且增强CNE1细胞与基底膜的粘附能力、运动能力及侵袭能力。     

Differential Effect of TPA on Cell Growth and Epstein-Barr Virus Reactivation in Epithelial Cell Lines Derived from Gastric Tissues and B Cell Line Raji

We characterized the cell growth and Epstein-Barr virus (EBV) reactivation for EBV infected epithelial cell lines, GT38, GT39, and GTC-4 using 12-O-tetradecanoylphorbol-13-acetate (TPA). These cell lines grew similarly in liquid medium, and formed colonies in soft agar. The cell growth was inhibited with TPA, dose-dependently in liquid medium. The colony formation was enhanced with low concentrations of TPA, but was inhibited with high concentrations. The latent EBV was reactivated with high concentrations of TPA as shown by the expression of EBV BZLF1 gene product ZEBRA. The effects of TPA on GTC-4 were compared with a Burkitt's lymphoma cell line Raji. The mode of actions of TPA in GTC-4 was different from Raji in terms of cell growth and EBV reactivation. The effective concentrations of TPA for cell growth inhibition and EBV reactivation were higher in Raji than GTC-4. Cell cycle analysis showed that TPA (20 ng/ml) induced cell cycle arrest to Raji but not to GTC-4; however, the rate of trypan blue stained cells increased in the TPA treated GTC-4 but not Raji. These results demonstrated that TPA affects differentially for the stimulation and inhibition of cell growth, and also EBV reactivation depends on TPA concentrations and cell types.     

EB病毒转化的永生性人B淋巴母细胞中MTHFR基因的表达

ＨｐＳＶ２－ｎｅｏ质粒作为载体，在ＥｃｏＲＩ酶切位点上插入小鼠金属充蛋白（ＭＴ－Ｉ）基因，然后用ＤＮＡ－磷酸钙介导的基因转移法将重组质粒转染ＨｅＬａ细胞，经筛选得到表达ＭＴ－Ｉ的抗性细胞克隆，经检测，Ｇ４１８抗性细胞内有ＭＴ的特异性表达，表达量是未围染细胞的２．６倍。用不同浓度顺铂、阿霉素处理细胞，观察ＭＴ－Ｉ基因的表达与ＨｅＬａ细胞耐药性的关系。结果表明：０．１μｍｏｌ／ｍｌ顺铂作用细胞７２ｈ后