一种测定血清或体液TNF浓度的方法─—细胞毒法

一种测定血清或体液ＴＮＦ浓度的方法─—细胞毒法樊晓晖，高枫，冷静，王乃平，张唯嘉，源一郎肿瘤坏死因子（ＴｕｍｏｒＮｅｃｒｏｓｉｓＦａｃｔｏｒ，ＴＮＦ）是一种具有多种生物学效应的重要的细胞因子［１］，它由激活的巨噬细胞和单核细胞分泌，主要是介导抗肿瘤及...

补体介导细胞毒法检测晚期癌症患者外周血T细胞亚群初步报告

采用补体介导细胞毒方法检测15例晚期癌症患者外周血T细胞亚群。结果发现：CD4细胞降低，CD8细胞升高，CD4／CD8＜1．0．该法稳定、可靠、经济、简便．

流式细胞仪检测人类白细胞抗原-B27与微量细胞毒法的比较

人类白细胞抗原-B27（human leucocyte antigen，HIL-B27）是HLA-I类分子基因中B位点上的1个等位基因，是经典的HIA位点编码的I类主要组织相容性复合物基因产物之一。表达在细胞表面的I类分子是由HIL编码的重链、B2微球蛋白和内源性多肽形成的稳定的三聚体复合物，其相对分子质量为44000。现已证实HIL-B27有11个亚类，其中HIL-B2705是大多数非亚洲人群的主要亚类，而HIL-B2704则是中国人和许多其他亚洲人群最多见的亚类。该基因与多种疾病有相关性，与强直性脊柱炎（ankylosing spoildylitis，AS）相关性最高。

ELISA法和CDC法检测群体反应性抗体的比较

目的探讨检测移植受者群体反应性抗体(PRA)的ELISA法和补体依赖性细胞毒法的不同之处。方法①ELISA法检测采用美国One lambda公司或美国GIT公司抗原板检测PRA。②补体依赖细胞毒法(Complement dependent cytotoxicity,CDC)检测采用德国Biotest公司细胞板检测PRA。③对ELISA法抗原筛选板检测出均呈阳性反应的肾移植前患者血清,再经CDC法细胞板检测。结果296例肾移植前患者血清经两种抗原板检测36例呈阳性反应,说明采用ELISA法抗原板无论是筛选板还是鉴定板,两者无差异;而前法36例PRA阳性血清经过CDC法细胞板鉴定,则表现出大多数呈阴性反应。结论ELISA法抗原板的敏感性高,检测出的PRA值高;而CDC法细胞板与抗体的强度和量有一定的要求,则反应的PRA值低。CDC法细胞板的优势是在补体的参与下完成的试验,其更能体现移植受者体内的情况。

用单克隆抗体免疫毒素体外净化自体骨髓移植的研究

体外净化骨髓中残留自血病细咆的方法，以免疫学方法特异性最强。我们与军事医学科学院协作，从1988年5月开始应用补体介导细胞毒法和单克隆抗体与蓖麻毒素偶联制备成免疫毒素在体外净化白血病细胞后进行ABMT研究。共计7例，全部成功，现报道如下：

XRCC1 and DNA polymerase β in cellular protection against cytotoxic DNA single-strand breaks

Single-strand breaks （SSBs） can occur in cells either directly, or indirectly following initiation of base excision repair （BER）. SSBs generally have blocked termini lacking the conventional 5＇-phosphate and 3＇-hydroxyl groups and require further processing prior to DNA synthesis and ligation. XRCC1 is devoid of any known enzymatic activity, but it can physically interact with other proteins involved in all stages of the overlapping SSB repair and BER pathways, including those that conduct the rate-limiting end-tailoring, and in many cases can stimulate their enzymatic activities. XRCC1^-/- mouse fibroblasts are most hypersensitive to agents that produce DNA lesions repaired by monofunctional glycosylase-initiated BER and that result in formation of indirect SSBs. A requirement for the deoxyribose phosphate lyase activity of DNA polymerase β （pol β） is specific to this pathway, whereas pol β is implicated in gap-filling during repair of many types of SSBs. Elevated levels of strand breaks, and diminished repair, have been demonstrated in MMS- treated XRCC1^-/-, and to a lesser extent in pol β^-/- cell lines, compared with wild-type cells. Thus a strong correlation is observed between cellular sensitivity to MMS and the ability of cells to repair MMS-induced damage. Exposure of wild-type and polβ^-/- cells to an inhibitor of PARP activity dramatically potentiates MMS-induced cytotoxicity. XRCC1^-/- cells are also sensitized by PARP inhibition demonstrating that PARP-mediated poly（ADP-ribosyl）ation plays a role in modulation of cytotoxicity beyond recruitment of XRCC 1 to sites of DNA damage.

Antiproliferation and apoptosis induction of paeonol in HepG_2 cells

AIM： To investigate the antiproliferative effect of paeonol （Pae） used alone or in combination with chemotherapeutic agents [cisplatin （CDDP）, doxorubicin （DOX） and 5-fluorouracil （5-FU）] on human hepatoma cell line HepG2 and the possible mechanisms. METHODS： The cytotoxic effect of drugs on HepG2 cells was measured by 3-（4, 5-dimethylthiazol-2- yl）-2, 5-diphenyltetra-zolium bromide （MTT） assay. Morphologic changes were observed by acridine orange （AO） fuorescence staining. Cell cycle and apoptosis rate were detected by flow cytometry （FCM）. Drug-drug interactions were analyzed by the coefficient of drug RESULTS： Pae （7.81-250 mg/L） had an inhibitory effect on the proliferation of HepG2 cells in a dose-dependent manner, with the IC50 value of （104.77±7.28） mg/L. AO fluorescence staining and FCM assays showed that Pae induced apoptosis and arrested cell cycle at S phase in HepG2 cells. Further, different extent synergisms were observed when Pae （15.63, 31.25, 62.5 rag/L） was combined with CDDP （0.31-2.5 mg/L）, DOX （0.16-1.25 mg/L）, or 5-FU （12.5-100 mg/L） at appropriate concentrations. The IC50 value of the three drugs decreased dramatically when combined with Pae （P 〈 0.01）. Of the three different combinations, the sensitivity of cells to drugs was considerably different.CONCLUSION： Pae had a significant growth-inhibitory effect on the human hepatoma cell line HepG2, which may be related to apoptosis induction and cell cycle arrest. It also can enhance the cytotoxicity of chemotherapeutic agents on HepG2 cells, and the S phase arrest induced by Pae may be one of the mechanisms of these interactions.

Interference of Hepatitis B Virus with Cellular Signaling

The presence of hepatitis B virus (HBV) proteins leads to changes in the cellular gene expression. As a consequence, the cellular signaling processes are influenced by the actions of HBV proteins. It has been shown that HBV nucleocapsid protein and the amino-terminal part of polymerase termed as terminal protein (TP) could inhibit interferon signaling. Further, the global gene expression profiles differ in hepatoma cells with and without HBV gene expression and replication. The expression of interferon (IFN) stimulated genes (ISGs) was differently regulated in cells with HBV replication and could be modulated by antiviral treatments. The HBV TP has been found to modulate the ISG expression and enhance the HBV replication. The modulation of the cellular signaling processes by HBV may have significant implications for pathogenesis.

Detection of apoptosis induced by new type gosling viral enteritis virus in vitro through fluorescein annexin V-FITC/PI double labeling

AIM: To achieve a better understanding of the pathogenesis of new type gosling viral enteritis virus (NGVEV) and the relationship between NGVEV and host cells. METHODS: The apoptosis of duck embryo fibroblasts (DEF) induced by NGVEV was investigated by fluorescence-activated cell sorter (FACS) and fluorescence microscope after the cells were stained with Annexin V-FITC and propidium iodide (PI). RESULTS: By staining cells with a combination of fluorescein annexin V-FITC and PI, it is possible to distinguish and quantitatively analyze non-apoptotic cells (Annexin V-FITC negative/PI negative), early apoptotic cells (Annexin V-FITC positive/PI negative), late apoptotic/necrotic cells (Annexin V-FITC positive/ PI positive) and dead cells (Annexin V-FITC negative/PI positive) through flow cytometry and fluorescence microscope. The percentage of apoptotic cells increased with the incubation time and reached a maximum at 120 h after infection, while the percentage of non- apoptotic cells decreased.

Role of upper endoscopy in diagnosing opportunistic infections in human immunodeficiency virus-infected patients

Highly active antiretroviral therapy (HAART) has dramatically decreased opportunistic infections (OIs) in human immunodef iciency virus (HIV)-infected patients. However,gastrointestinal disease continues to account for a high proportion of presenting symptoms in these patients. Gastrointestinal symptoms in treated patients who respond to therapy are more likely to the result of drug-induced complications than OI. Endoscopic evaluation of the gastrointestinal tract remains a cornerstone of diagnosis,especially in patients with advanced immunodeficiency,who are at risk for OI. The peripheral blood CD4 lymphocyte count helps to predict the risk of an OI,with the highest risk seen in HIV-infected patients with low CD4 count (< 200 cells/mm3). This review provides an update of the role of endoscopy in diagnosing OI in the upper gastrointestinal tract in HIV-infected patients in the era of HAART.

Down-regulation of IL-8 expression in human airway epithelial cells through helper-dependent adenoviral-mediated RNA interference

Interleukin (IL)-8 is a potent neutrophil chemotactic factor and a crucial mediator in neutrophil-dependent inflammation.Various cell types produce IL-8, either in response to external stimuli such as cytokines or bacterial infection, or aftermalignant transformation. Anti-IL-8 strategies have been considered for anti-inflammatory therapy. In this paper wedemonstrate that the RNA interference technique can be used to efficiently down-regulate IL-8 protein expression inairway epithelial cells. We used a helper-dependent adenoviral vector to express a small hairpin (sh)RNA targetinghuman IL-8 in cultured airway epithelial cells (IB3-1, Cftr-/-; C38, Cftr-corrected) stimulated with TNF-α, IL-1β orheat-inactivated Burkholderia cenocepacia. Stimulated IL-8 expression in IB3-1 and C38 cells was significantly reducedby shRNA expression. The shRNA targeting IL-8 had no effect on the activation of NF-κB, or on the protein levels ofIκB or IL-6, suggesting that this anti-IL-8 strategy was highly specific, and therefore may offer potential for thetreatment of inflammatory diseases.

Functional Analyses of Mammalian Reovirus Nonstructural Protein μNS

Genome replication of reovirus occurs in cytoplasmic inclusion bodies called viral factories or viroplasms. The viral nonstructural protein uNS, encoded by genome segment M3, is not a component of mature virions, but is expressed to high levels in infected cells and is concentrated in the infected cell factory matrix. Recent studies have demonstrated that uNS plays a central role in forming the matrix of these structures, as well as in recruiting other components to them for putative roles in genome replication and particle assembly.

Low-dose intermittent interferon-alpha therapy for HCV-related liver cirrhosis after curative treatment of hepatocellular carcinoma

AIM: To assess the efficacy of low-dose intermittent interferon (IFN) therapy in patients with hepatitis C virus (HCV)-related compensated cirrhosis who had received curative treatment for primary hepatocellular carcinoma (HCC). METHODS: We performed a prospective case controlled study. Sixteen patients received 3 MIU of natural IFN- alpha intramuscularly 3 times weekly for at least 48 wk (IFN group). They were compared with 16 matched historical controls (non-IFN group). RESULTS: The cumulative rate of first recurrence of HCC was not significantly different between the IFN group and the non-IFN group (0% vs 6.7% and 68.6% vs 80% at 1- and 3-year, P = 0.157, respectively). The cumulative rate of second recurrence was not also significantly different between the IFN group and the non-IFN group (0% vs 6.7% and 35.9% vs 67% at 1- and 3-year, P = 0.056, respectively). Although the difference in the Child-Pugh classification score between the groups at initial treatment of HCC was not signifi cant, the score was signifi cantly worse at the time of data analysis in the non-IFN group than IFN group (7.19 ± 1.42 vs 5.81 ± 0.75, P = 0.0008). The cumulative rate of deviation from objects of any treatment for recurrentHCC was also higher in the non-IFN group than IFN group (6.7% and 27% vs 0 and 0% at 1- and 3-year, P = 0.048, respectively). CONCLUSION: Low-dose intermittent IFN-alpha therapy for patients with HCV-related compensated cirrhosis after curative HCC treatment was effective by making patients tolerant to medical or surgical treatment for recurrent HCC in the later period of observation.

Induction of cytotoxic T lymphocyte respones in vivo after immunotherapy with dendritic cells in patients with nasopharyngeal carcinoma

The aim of the present study was to determine the efficacy of immunotherapy with dendritic cells to elicit EBV-specific CTL-immunity in advanced cases of EBV-positive patients with nasopharyngeal carcinoma （NPC） and to determine the safety and toxicity of this preparation. Nine cases of histologically confirmed patients with NPC undergoing treatment with radiological therapy were enrolled in this study. Dendritic cells, generated in vitro from blood monocytes of patients were cultured and matured with cytokines and then infected with recombinant adenovims vaccine containing EBV-latent membrane protein-2 （Ad-LMP2）. On 9 days＇ cultivation of cells, the matured DCs were harvested, irradiated with 60^Co and then injected intradermally to patients with NPC. The injections were performed 3 times totally. After immunization, the CTL responses were assayed by means of cytotoxicity and epitope-specific IFN-γ production. The results of this trial showed that all patients could tolerate this kind of treatment without any side effect, during which marked increase of LMP2-specific CIL-responses could be demonstrated in 5 patients of this group. And the level of IgA/VCA antibody decreased in 8 of 9 patients, thus accounting for a better prognosis for these patients. All patients will be followed up for another one year. At least, the present work shows that intradermal vaccination with autologons DCs infected with recombinant Ad-LMP2 adenovirus is a safe procedure in NPC patients, in which this procedure can enhance the LMP2-specific CTL responses in patients. These data are encouraging to develop more effective vaccine strategies for the treatment of nasopharyngeal carcinoma.

A new ketosteroid from red alga Acanthophora spicifera

A new ketosteroid, along with six known steroids, was isolated from the ethanolic extracts of red alga Acanthophora spicifera （Vahl.） Boergesen. The structures, identified using chemical and spectroscopic methods including 2D NMR, were： （1） 22-hydroxy-5α-eholest-3,6-dione, （2） 6-hydroxycholest-4-ene-3-one, （3） cholest-4-ene-3,6-dione, （4） cholest-5-ene-3β-ol, （5） 5u-cholestane-3,6-dione, （6） β-Sitosterol and （7） Saringosterol. The MTT method was used to test the cytotoxicity of the compounds against the human cancer cell lines, HCT-8, Bel-7402, BGC-823, A549 and HELA. Compounds 1, 2, 3 and 5 showed moderate cytotoxic activity against human cancer cell lines.

The effect and significance on Akt and PTEN expression in melanoma B16 cells with chamaejasme extract

Objective: The aim of this study was to investigate the effect on Akt and PTEN expression and the mechanism of proliferation and apoptosis of melanoma B16 cells treated with chamaejasme extract. Methods: The expressions of Akt and PTEN of B16 cells treated with different concentrations of chamaejasme extract were detected with immunohistochemical method, cell apoptosis index(AI) was calculated with in situ labeling method. Results: Akt expressions of B16 cells treated with different concentrations of chamaejasme extract were significantly lower than the control group, while the PTEN expressions significantly up-regulated, and the effects appeared to be dose-related(P < 0.05). The Akt/AI of B16 cells treated with different concentrations of chamaejasme extract was significantly lower than the control group, all the parameters had extremely difference(F = 24.58, P < 0.05). Conclusion: Chamaejasme extract can inhibit proliferation and induce apoptosis of malignant melanoma B16 cells by down-regulating the expression of Akt and up-regulating the expression of PTEN.

Retrovirus-mediated herpes simplex virus thymidine kinase gene therapy approach for hepatocellular carcinoma

The therapeutic effect of herpes simplex virus thymidine kinase/ganciclovir (HSV-tk/GCV) system on hepatocellular carcinoma was studied in this experiment. The tk-containing retroviral recombinants were used to infect hepatoma cells (BEL-7402) and the cells were treated with ganciclovir (0-1000 microg/ml). The results showed that HSV-tk gene could be efficiently transferred in vitro into hepatoma cells and stably expressed. The growth potential of the tk-containing cells was significantly inhibited by GCV (P

Construction of genetically engineered macrophages expressing Smad6 and Smad7 genes with adeno-associated virus

Objective: To construct the genetically engineered macrophages expressing Smad6 and Smad7 genes with adeno-associated virus (AAV). Methods: The plasmids containing pcDNA3-Smad6/Flag and pcDNA3-Smad7/Flag were digested with BamHⅠ and XhoⅠ, respectively. Then the Smad6/Flag and Smad7/Flag gene segments obtained were cloned into plasmid pAAV-MCS respectively to construct the recombinant pAAV-Smad6/Flag and pAAV-Smad7/Flag plasmids. The resulting recombinant plasmids (pAAV-Smad6/Flag or pAAV-Smad7/Flag) or pAAV-LacZ plasmid were co-transfected into the HEK 293cells with pHelper and pAAV-RC by calcium-phosphate precipitation method. Recombinant AAV-2 viral particles were prepared from infected HEK293 cells and then were used to infect mouse macrophages. The expressions of Smad6 and Smad7 in macrophages were detected by immunocytochemical staining and expression of b-galactosidase was evaluated by X-gal staining. Results: The recombinant AAV vector containing Smad6 or Smad7 genes was successfully constructed. More than 95% macrophage cells expressed X-gal and Smad6 and Smad7 genes at 72 h after infection. Conclusion: These results indicate that the genetically engineered macrophages can express Smad6 and Smad7 proteins effectively, laying the foundation for the studies of TGF-β-induced diseases in vivo and highlighting the feasibility of macrophage-based gene therapy.