三种免疫抑制药对分化的巨噬细胞表型和功能的影响

目的 探讨3种免疫抑制药(雷帕霉素、环孢霉素A和紫杉醇)在骨髓前体细胞分化过程中对分化的巨噬细胞表型和功能的影响.方法 取60只C57BL/6小鼠颈椎脱臼致死,无菌操作制备骨髓前体细胞,在细胞培养体系中分别加入雷帕霉素(100μmol/L)、环孢霉素A(1mg/L)和紫杉醇(20μg/L)和巨噬细胞集落刺激因子,通过混...     

5-氟尿嘧啶诱导人肺腺癌A549细胞自噬

目的 探讨5-氟尿嘧啶(5-FU)是否诱导人肺腺癌A549细胞发生自噬.方法 吖啶橙(AO)荧光染色和透射电镜观察自噬泡的变化;细胞免疫化学法测定LC3-Ⅱ的表达;流式细胞术及吖啶橙染色结合激光扫描共焦显微镜检测细胞凋亡;DNA电泳检测凋亡梯形条带的产生.结果 吖啶橙荧光染色和透射电镜观察结果显示,5-氟尿嘧啶处理细胞...     

干扰素-γ诱导大鼠肠黏膜微血管内皮细胞表达细胞黏附因子-1和干扰素-γ受体α

目的 以体外培养的大鼠肠黏膜微血管内皮细胞(RIMMVECs)为研究对象,探讨干扰素-γ(IFN-γ)对于体外培养的RIMMVECs表达细胞黏附因子-1(ICAM-1)和IFN-γ受体α(IFN-γRα)的影响.方法 体外分离培养RIMMVECs,用不同浓度的IFN-γ对所培养的RIMMVECs进行诱导,通过荧光定量RT-PCR法和流式细胞术,从mRNA和蛋白水平检测活化后的RIMMVECs表达ICAM-1和IFN-γRα的情况.结果 浓度为20 μg/L和40 μg/L的 IFN-γ可以激活RIMMVECs,在mRNA和蛋白水平均能提高ICAM-1的表达,并且6 h时达到高峰;20 μg/L的IFN-γ刺激RIMMVECs后,可使其上调表达IFN-γRα mRNA,但是蛋白表达量却随着刺激时间逐渐降低;而40 μg/L的IFN-γ刺激RIMMVECs 2 h后,IFN-γRα mRNA 达到峰值,6 h之后,其表达量呈下降趋势,IFN-γRα蛋白浓度也随之逐渐降低;10 μg/L的IFN-γ对于ICAM-1和IFN-γRα的表达无影响.结论 IFN-γ可能是通过影响微血管内皮细胞(MVECs)表面IFN-γRα分子和ICAM-1的表达,从而调控和参与细胞免疫反应和炎症反应.     

Further development of the rat Pig-a mutation assay: measuring rat Pig-a mutant bone marrow erythroids and a high throughput assay for mutant peripheral blood reticulocytes

Recent studies indicate that the Pig-a assay is a promising tool for evaluating in vivo mutagenicity. We have developed novel rat Pig-a assays that facilitate measuring mutant frequencies in two early arising populations of blood cells, bone marrow erythroids (BMEs) and peripheral blood (PB) reticulocytes (RETs). In these assays, bone marrow cells of erythroid origin and PB red blood cells (RBCs) were identified using an antibody against rat erythroid-specific marker HIS49. In addition, RETs were selectivity enriched from PB using magnetic separation of cells positive for CD71, a transferrin receptor expressed on the surface of BMEs and RETs, but not on the surface of mature RBCs. With magnetic enrichment, more than 1 x 10(6) CD71-positive RETs could be evaluated by flow cytometry for Pig-a mutant frequency within 5 to 8 min. CD59-deficient RET and BME frequencies of more than 100 x 10(-6) and 80 x 10(-6) were detected 1 week after treating rats with 40 mg/kg N-ethyl-N-nitrosourea; by comparison, the frequency of CD59-deficient total RBCs in these rats was 13.2 x 10(-6). The frequency of spontaneous Pig-a mutant RETs and BMEs was less than 5 x 10(-6) and 15 x 10(-6), respectively. Since approximately 98% of nucleated cells in the BME fraction were erythroblasts, it should be possible to use BMEs to determine the spectrum of CD59-deficient Pig-a mutations in cells of erythroid lineage. Conducting concurrent Pig-a assays on RETs and BMEs may be useful for evaluating the in vivo mutagenicity of chemicals, especially when prolonged mutant manifestation is not feasible or when the confirmation of mutation induction is necessary.     

Monitoring humans for somatic mutation in the endogenous PIG-a gene using red blood cells

The endogenous X-linked PIG-A gene is involved in the synthesis of glycosyl phosphatidyl inositol (GPI) anchors that tether specific protein markers to the exterior of mammalian cell cytoplasmic membranes. Earlier studies in rodent models indicate that Pig-a mutant red blood cells (RBCs) can be induced in animals treated with genotoxic agents, and that flow cytometry can be used to identify rare RBCs deficient in the GPI-anchored protein, CD59, as a marker of Pig-a gene mutation. We investigated if a similar approach could be used for detecting gene mutation in humans. We first determined the frequency of spontaneous CD59-deficient RBCs (presumed PIG-A mutants) in 97 self-identified healthy volunteers. For most subjects, the frequency of CD59-deficient RBCs was low (average of 5.1 ± 4.9 × 10(-6) ; median of 3.8 × 10(-6) and mutant frequency less than 8 × 10(-6) for 75% of subjects), with a statistically significant difference in median mutant frequencies between males and females. PIG-A RBC mutant frequency displayed poor correlation with the age and no correlation with the smoking status of the subjects. Also, two individuals had markedly increased CD59-deficient RBC frequencies of ～300 × 10(-6) and ～100 × 10(-6) . We then monitored PIG-A mutation in 10 newly diagnosed cancer patients undergoing chemotherapy with known genotoxic drugs. The frequency of CD59-deficient RBCs in the blood of the patients was measured before the start of chemotherapy and three times over a period of ～6 months while on/after chemotherapy. Responses were generally weak, most observations being less than the median mutant frequency for both males and females; the greatest response was an approximate three-fold increase in the frequency of CD59-deficient RBCs in one patient treated with a combination of cisplatin and etoposide. These results suggest that the RBC PIG-A assay can be adopted to measuring somatic cell mutation in humans. Further research is necessary to determine the assay's sensitivity in detecting mutations induced by genotoxic agents acting via different mechanisms.     

In vitro micronucleus screening of pharmaceutical candidates by flow cytometry in Chinese hamster V79 cells

We previously reported a high concordance of in vitro micronucleus (MNvit) results obtained by flow cytometry to the known cytogenetic activity often commercially available compounds mentioned as validation compounds in an early draft of the OECD MNvit TG487 [Bryce et al., 2010; Organization for Economic Co-operation and Development(OECD), 2007]. The current study investigated this method in Chinese hamster V79 cells with pharmaceutical compounds of unknown genotoxic potential. Twenty-five compounds from several therapeutic areas such as oncology, neuroscience and immunological research were tested in the flow cytometry assay, and for comparison using the cytokinesis-block microscopy assay. Five of these 25 compounds were considered positive for micronucleus induction by the microscopy assessment. In all cases, the results from the flow cytometry assess ment matched the results of the microscopy assay. Thus, flow cytometry is a viable method for assessing the aneugenic/clastogenic potential of pharmaceutical drug candidates. The flow method offered several advantages over traditional microscopy. For instance, the ratio of micronuclei (MN) to 10,000 nuclei was evaluated in less than 2 min vs.15 min to manually assess 600 binucleate cells. Evaluation by flow cytometry can be automated,freeing resources and eliminating scorer fatigue.The assay may also provide for mechanistic understanding of MN formation based on size and the ratio of nuclei with sub-2N DNA content, allowing for discrimination between aneugenic and clastogenic compounds.     

新疆乌鲁木齐地区142例急性白血病流式细胞术免疫分型研究

目的:研究新疆乌鲁木齐地区急性白血病(AL)患者免疫表型特征及分布特点。方法:选用细胞表面分子CD20、CD14、CD3、CD2、CD33、HLA-DR、CD15、CD10、CD5、CD22、CD7、CD13、CD34、CD11b、CD19、CD117等的单克隆抗体,采用流式细胞仪CD45/SSC双参数散点图设门法对142例AL患者进行免疫表型分析。结果:35例急性淋巴细胞白血病(ALL),其中6例伴有髓系抗原的表达(14.3%)且表达最频繁的为CD13;96例急性髓系白血病(AML),其中21例伴有淋系抗原的表达(21.9%)且表达最频繁的为CD7;11例为FAB难以分类的急性白血病(UAL),兼有淋系和髓系抗原的表达。ALL免疫分型特点在新疆汉族和维吾尔族(简称维族)中差异无统计学意义(P>0.05),在AML中,汉族髓系抗原的表达率依次为CD13>CD33>CD15,维族髓系抗原的表达率依次为CD13>CD15>CD14,且维族患者多伴有淋系抗原CD7的表达。结论:FCM免疫分型是在细胞形态学和细胞染色基础上对AL诊断与分型的重要补充,免疫表型的检测对AL的诊断和治疗有重要意义。     

Adult T-cell leukemia/lymphoma with Epstein-Barr virus-positive Hodgkin-like cells

Hodgkin-like cells have been described in a variety of non-Hodgkin lymphomas including chronic lymphocytic leukemia and peripheral T-cell lymphoma. There have been rare reports in the Japanese population of human T-cell lymphotrophic virus-1-associated adult T-cell leukemia/lymphoma harboring Hodgkin-like cells; however, no similar cases have been described in Western patients. We report a 53-year-old African American man who presented with progressive weakness and lethargy, and was found to have generalized lymphadenopathy and hypercalcemia. A lymph node biopsy showed involvement by adult T-cell leukemia/lymphoma with scattered Epstein-Barr virus-positive cells, some of which resembled Hodgkin cells that had a B-cell phenotype, consistent with an Epstein-Barr virus-lymphoproliferative disorder. The patient had stage 4 disease with bone marrow involvement. In light of the associated B-cell lymphoproliferative process, the patient was treated with 6 cycles of intensive chemotherapy that targeted both the adult T-cell leukemia/lymphoma and the Epstein-Barr virus-lymphoproliferative disorder that resulted in a complete response. An awareness of the association of Epstein-Barr virus-lymphoproliferative disorder with Hodgkin-like cells in the context of adult T-cell leukemia/lymphoma is necessary to avoid potential misdiagnosis and to aid in therapeutic decisions.     

Immunoassay of lymphocyte subsets in ovine palatine tonsils

By means of immunohistochemistry (IHC) and triple color flow cytometry (FCM), five commercial antibodies (anti-CD2, CD4, CD8, CD21, and CD45) were evaluated to quantify and localize the B- and T-lymphocytes in the ovine palatine tonsil. The results of both techniques were compared and evaluated. For the immunohistochemical analysis, three fixation methods were evaluated for their suitability to localize the different lymphocyte populations: 3.5% formaldehyde, zinc salts-based fixative and cryopreservation. The anti-CD45 antibody showed a positive reaction after all three fixation methods. The four other antibodies tested (anti-CD2, CD4, CD8 and CD21) were compatible with zinc salts-based fixation and cryopreservation. The CD21+ B-lymphocytes were localized in the tonsillar lymphoid follicles, while the CD2+ T-lymphocytes were abundant in the interfollicular regions and rare within the lymphoid follicles. The CD8+ T-cells were concentrated adjacent to the follicles, while the CD4+ T-cells were localized in the interfollicular zones as well as in the follicles. Both by immunohistochemistry and flow cytometry, a quantification of the different lymphocyte subsets was made. When comparing the results, a reversed B/T cell ratio was noticed. Possible explanations for this observation are discussed.