Cytogenetic effects of vincristine sulfate and ethylene dibromide in human peripheral lymphocytes: micronucleus analysis.

Micronuclei kinetics and persistence in mononucleated and binucleated human peripheral lymphocytes following short-term (4 hr) and continuous (until harvest) in vitro exposure to vincristine sulfate (VS) and ethylene dibromide (EDB) were studied. Lymphocytes were exposed to chemicals for various doses and harvested at different culture times. Micronucleus frequencies were scored in both mononucleated and binucleated cells on the same slide. VS-treated cells showed a significantly higher incidence of micronucleus in both mononucleated and binucleated cells than controls (P less than 0.01). The cells treated continuously with VS produced comparatively higher frequencies of micronucleated cells than those treated for 4 hr. Highest micronuclei frequencies were observed 24 hr after chemical treatment in both mononucleated and binucleated cells and decreased later with time. However, the micronucleus frequencies remained significantly higher than the controls even in the cells harvested at 144 hr. VS induced a large number of micronucleated cells with multiple micronuclei. VS also caused a severe decrease in nuclear division due to cytotoxic effect. Lymphocytes treated with EDB for 4 hr and continuously showed a statistically higher incidence of micronuclei in binucleated cells compared to the controls (P less than 0.05), whereas in mononucleated cells higher micronucleus frequencies were observed only in cultures treated continuously. Continuous presence of EDB induced both dose- and time-dependent increase of micronuclei in both mono- and binucleated cells (P less than 0.05). EDB induced relatively few multiple micronucleated cells in comparison with VS. EDB did not affect nuclear divisions even with continuous treatment. High micronucleus frequencies observed at 144 hr harvest following 4 hr treatment of both EDB and VS suggest the persistence of DNA damage in cells. These studies suggest that micronuclei kinetics in human peripheral lymphocytes depends on the genotoxic potentially and cytotoxicity of a genotoxicant.     

Peanut-specific B and T cell responses are correlated in peanut-allergic but not in non-allergic individuals

Objective We aim to find what is the relationship between B cell antibody responses and specific T cell help in the specific cases of allergy and tolerance to peanuts. Background B cell antibody responses to foreign proteins usually depend upon antigen‐specific T cell help. However, specific antibody levels can sometimes be maintained lifelong after infections or vaccination. Methods We measured peanut‐specific proliferation and antibody levels in peanut‐allergic and non‐allergic children using tritiated thymidine incorporation and UniCAP, respectively. We also investigated the corresponding tetanus toxoid specific responses in both groups. Results We found that tetanus‐specific IgG did not correlate with lymphocyte proliferation (Spearman rank correlation coefficient r′=0.08, P=0.74) nor with tetanus‐specific cytokine production (IFN‐γ: r′=0.198, P=0.285; TNF‐α: r′=0.274, P=0.146; IL‐4: r′=?0.007, P=0.96; P=0.221; IL‐13: r′=0.363, P=0.056). Conversely, in peanut‐allergic donors, peanut‐specific IgE (average 21 kU/L, median 2.27 kU/L, range 0.34‐100 kU/L) but not peanut‐specific IgG was positively correlated with proliferation (r′=0.751, P=0.003). In these donors, specific IgE was positively correlated with peanut‐specific Th2 cytokines production: r′=0.635, P=0.02 for IL‐4 and r′=0.641, P=0.025 for IL‐13 and negatively correlated with Th1 cytokines (r′=?0.71, P=0.007 for IFN‐γ and r′=?0.746, P=0.005 for TNF‐α, respectively). However, peanut‐specific IgE was not correlated with T cell proliferation or cytokine production in non‐allergic individuals. In conclusion, in allergic individuals, B and T cell responses to peanut antigens are correlated whereas normal immune responses B and T cell responses are uncoupled. Conclusion Our results support the view that B cell responses to allergens but not those to non‐allergenic proteins are correlated with specific T cell responses and therefore specific immunotherapy targeting of such T cells would inhibit allergen‐specific B cells.     

T细胞非霍奇金淋巴瘤的药物治疗

近年来出现了多种针对T细胞非霍奇金淋巴瘤(T-NHL)的新的治疗药物,如核苷类似物、新型BCR/ABL酪氨酸激酶抑制剂、左旋门冬酰胺酶、蛋白酶体抑制剂、细胞因子类药物及单克隆抗体等,在治疗中都显示出一定的疗效.     

Vβ8+ T lymphocytes are essential in the regulation of airway hyperresponsiveness and bronchoalveolar eosinophilia but not in allergen-specific IgE in a murine model of allergic asthma

BACKGROUND: There is increasing evidence that in allergic asthma the inflammatory process is regulated by T lymphocytes. In BALB/c mice the majority of ovalbumin responsive T lymphocytes express the Vbeta8.1+ and Vbeta8.2+ T-cell receptor. OBJECTIVE: We analysed the contribution of Vbeta8+ T lymphocytes during the sensitization and challenge phase in the regulation of antigen-specific IgE, airway hyperresponsiveness and cellular infiltration in the airways in a murine model of allergic asthma. METHODS: Mice strains genetically lacking (SJL/J and SJA/9) and expressing (BALB/c) the Vbeta8+ T cell receptor were used. In addition, prior to the sensitization and prior to the challenge BALB/c mice were treated with antibodies to Vbeta8. Mice were sensitized with ovalbumin, followed by repeated challenge with ovalbumin or saline aerosols. RESULTS: In ovalbumin challenged BALB/c mice treated with control antibody a significant increase in eosinophils in the bronchoalveolar lavage, airway hyperresponsiveness and increased serum levels of ovalbumin-specific IgE were observed compared to control mice. Treatment of BALB/c mice with antibodies to Vbeta8 prior to the sensitization or prior to the challenge period completely inhibited the ovalbumin induced infiltration of eosinophils and airway hyperresponsiveness, while ovalbumin-specific IgE was slightly decreased. In SJA/9 and SJL/J mice ovalbumin challenge did not induce eosinophilic infiltration and airway hyperresponsiveness. In SJL/J mice ovalbumin challenge induced an upregulation of ovalbumin-specific IgE, however, in SJA/9 mice no upregulation was observed. CONCLUSION: It is demonstrated that Vbeta8+ T lymphocytes are essential for infiltration of eosinophils in the airways and development of airway hyperresponsiveness in a murine model of allergic asthma. In contrast, although Vbeta8+ T lymphocytes seem to be important for the extent of IgE levels, no essential role for Vbeta8+ T lymphocytes in the induction of antigen-specific IgE was observed.     

Lipophilic Fluorochrome Trackers of Membrane Transfers between Immune Cells

Cell-to-cell transfers of membrane molecules between lymphoid cells (sometimes referred to as trogocytosis) is frequent and has multiple physiological consequences. Although difficult to visualize through the tracking of defined cell surface proteins, this process can be readily monitored by inserting PKH or CellVue Maroon fluorochromes into the plasma membranes of donor cells. We discuss here parameters that determine its detection by a flow-cytometry-based in vitro assay and present examples of application, including time-lapse video-microscopy analysis of transfers at the immunological synapse. By combining detection of cell-to-cell transfer and of cell surface CD107, it is possible to discriminate lymphoid cells binding target cells with and without perforin release. This could prove useful for identifying cells that destruct known target cells in autoimmune pathologies.

[Supplementary materials are available for this article. Go to the publisher's online edition of Immunological Investigations for the following free supplemental resources: movie files of Suppl Data 1 CellVue Maroon Synaptic Transfers, Suppl Data 2 Synaptic redistribution of CellVue Maroon, Suppl Data 3 lytic synapse and Suppl Data 4 Serial killer in action and jpeg of Suppl Data 5 Intensity of PKH67-transfer detection]     

红细胞CD35在抗原激活淋巴细胞免疫反应中的作用

目的探讨红细胞CD35在抗原激活淋巴细胞免疫反应中的作用。方法用淋巴细胞分离液分离健康成人ACD抗凝全血获得淋巴细胞悬液(1×106/ml)和红细胞悬液(1×108/ml),以灭活腹水癌细胞S180(1×106/ml)作为激活抗原,以自体血浆作为反应基质,考察红细胞对淋巴细胞的调控能力,流式细胞仪检测淋巴细胞表面CD25的表达阳性率。单抗封闭红细胞CD35或EDTA破坏补体,观察淋巴细胞CD25表达的变化。结果CD35单抗封闭后淋巴细胞CD25表达量(18·22%±4·27%)明显降低;EDTA破坏补体后,淋巴细胞CD25表达量(18·79%±3·90%)比ACD抗凝组(23·29%±4·40%)明显降低,与CD35阻断组基本相同,但仍高于Hanks′液对照组(13·19%±2·96%)。结论红细胞CD35和血浆补体对抗原激活淋巴细胞免疫反应起着重要的调控作用;血浆中还存在其他调控淋巴细胞活化的机制。促进红细胞表面CD35分子表达、保持血浆补体活性对提高淋巴细胞免疫活性有着重要意义。     

慢性乙型肝炎患者血清sIL-2R和IGF-1与淋巴细胞凋亡的关系

目的 研究慢性乙型肝炎患者血清可溶性白细胞介素-2受体（sIL-2R）和胰岛素样生长因子-1（IGF-1）与外周血淋巴细胞凋亡的关系，并探讨其临床意义。方法 分别采用放射免疫分析法和流式细胞计数仪检测慢性乙型肝炎患者血清sIL-2R、IGF-1和外周血淋巴细胞凋亡率。结果 慢性乙型肝炎患者血清sIL-2R、IGF-1水平和外周血淋巴细胞凋亡率明显高于正常对照组。随着患者肝脏病变程度的加重，外周血淋巴细胞凋亡率和血清sIL-2R水平逐步升高，而IGF-1水平则逐步降低。慢性乙型肝炎患者外周血淋巴细胞凋亡率与血清sIL-2R水平呈正相关，与IGF-1水平呈负相关。结论 慢性乙型肝炎患者外周血淋巴细胞凋亡的异常与血清sIL-2R、IGF-1水平的异常有关，三者的变化与患者肝脏病变程度相关。     

Characterization of the T cell response to the major hazelnut allergen, Cor a 1.04: evidence for a relevant T cell epitope not cross-reactive with homologous pollen allergens

BACKGROUND: IgE antibodies specific for the major birch-pollen allergen, Bet v 1, cross-react with homologous allergens in particular foods, e.g. apples, carrots and hazelnuts. In a high number of tree pollen-allergic individuals, this cross-reactivity causes clinical symptoms, commonly known as the 'birch-fruit-syndrome'. OBJECTIVE: To characterize the T cell response to the Bet v 1-related major allergen in hazelnuts, Cor a 1.04, and its cellular cross-reactivity with Bet v 1 and the homologous hazel pollen allergen, Cor a 1. METHODS: Using recombinant Cor a 1.04, T cell lines (TCL) and T cell clones (TCC) were established from peripheral blood mononuclear cells of tree pollen-allergic patients with associated food allergy. T cell epitopes were determined using overlapping synthetic peptides in Cor a 1.04-reactive TCL and TCC. In parallel, reactivity to Bet v 1 and Cor a 1 was tested. RESULTS: In total, 20 distinct T cell epitopes on the hazelnut allergen were identified. Several Cor a 1.04-specific TCL and TCC reacted with pollen allergens albeit less pronounced than with the hazelnut allergen. Several Cor a 1.04-specific TCC did not react with pollen allergens. Interestingly, these clones were found to react with the Bet v 1-related major allergen in carrots, Dau c 1. The cellular cross-reactivity between both food allergens could be associated with the most frequently recognized T cell epitope of Cor a 1.04, Cor a 1.04(142-153). CONCLUSIONS: The major hazelnut allergen cross-reacts with the major allergens of birch and hazel pollen but apparently contains a relevant T cell epitope not shared with pollen allergens. Our finding may have important implications for the specific immunotherapy of tree pollen-allergic patients suffering from concomitant hazelnut allergy.     

Cytotoxic lymphocytes in B-cell chronic lymphocytic leukemia

Summary The occurrence of cytotoxic lymphocyte subpopulations (i.e., CD 16⁺, CD57⁺ and cytotoxic CD 8⁺) was studied in the peripheral blood of 18 B-cell chronic lymphocytic leukemia (B-CLL) patients. The absolute numbers of CD 57⁺, CD 16⁺ and cytotoxic CD 8⁺ lymphocytes were increased in the peripheral blood of untreated patients as compared with healthy donors, suggesting a causal relation with the accumulation of malignant B-cells. For 5 B-CLL patients and 5 hematological normal donors, the lymphocyte subpopulations in peripheral blood, lymph nodes and bone marrow were determined. A significant immune response was observed in the lymph nodes of the patients, as reflected by the CD 3⁺ lymphocytes, which were 1.7–27 times larger in the patients lymph nodes than in their peripheral blood and bone marrow. In contrast, with peripheral blood this was mainly caused by an increase in CD 4⁺ lymphocytes. The CD 57 lymphocytes in the lymph nodes of the patients had abnormal orthogonal light-scattering signals and an abnormal density of CD 57⁺ receptors in comparison with their peripheral blood CD 57⁺ lymphocytes or the CD57⁺ lymphocytes in the peripheral blood, bone marrow and tonsils of the hematological normal donors. This study shows that although a significant increase of cytotoxic lymphocytes in the peripheral blood of B-CLL patients is observed, the actual distributions of the non-malignant lymphocytes can be quite different at the actual tumor sites, i.e., bone marrow and lymph nodes.