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1.
Regulatory T cells may be crucial in the development of T cell tolerance to malignancies and contribute to immune dysfunctions. We investigated the percentage, activity, and onset of apoptosis of T cell subpopulations by multicolor flow cytometry in metastatic epithelial cancer patients compared to normal controls. Furthermore, a possible relationship between the presence of circulating tumor cells detected by immunocytochemistry and immune cell abnormalities was evaluated. Our study demonstrated a significantly elevated proportion of regulatory T cells in cancer patients (p < 0.001). In contrast to all other T cell subpopulations, regulatory T cells showed comparable Annexin V-binding characteristics in patients and normal controls. No relationship between the detection of circulating tumor cells and immune dysfunction was observed. These results indicate that cancer patients have a higher number of regulatory T cells with resistance to apoptotic stimuli partly responsible for immune dysfunctions as often observed in cancer patients.  相似文献   

2.
In a selected group of human immunodeficiency virus (HIV)-infected patients we confirm the expansion of a CD8+ T-lymphocyte subset, i.e., the CD8+/Leu7+ cells, which account for 30% of the lymphocytes, compared to 3% in the control donors. In addition, a CD8+ T-lymphocyte subset that coexpresses class II (DR) antigens, i.e., CD8+/DR+ cells, is also increased from 1.5% in controls to 27% in the HIV-infected patients. Using three-color immunofluorescence and flow cytometry we can demonstrate that the CD8+/Leu7+ and the CD8+/class II+ cells are not distinct but overlapping subsets. In the HIV-infected patients 42% of the CD8+/Leu7+ cells were strongly positive for class II and these CD8+/Leu7+/class II+ cells accounted for 13% of all lymphocytes. These findings indicate that the expanded CD8+/Leu7+ cells are activated and hence might be actively involved in immune defense in acquired immune deficiency syndrome (AIDS).  相似文献   

3.
冉瑞琼  付华 《现代免疫学》1996,16(5):257-260
本文采用放射配基结合分析法和蛋白合成抑制试验研究了肿瘤坏死因子突变体(TNF-m)对SGC7901细胞TNF受体的影响。结果表明,TNF-m可显著降低SGC7901细胞表面TNF受体数目并呈剂量、时间、温度依赖关系,对受体亲和力无影响,TNF-m可使胞浆TNF受体数目增加,去除TNF-m3h后,膜TNF受体大约可恢复60%,显著高于胰蛋白酶处理组TNF受体的恢复率,放线菌素D对TNF-m处理的细胞TNF受体的抑制作用显著低于对照组,且TNF受体的半衰期约为90min.据此认为,TNF-m通过介导TNF受体的内化从而使膜TNF受体数降低。  相似文献   

4.
为研究肿瘤细胞MHCII类分子表达及对IFN γ诱导HLA分子表达的反应性与CIITA表达的关系 ,本文采用Westernblot、免疫组化和流式细胞术检测肿瘤细胞HLA分子表达 ,以RT PCR检测肿瘤细胞CIITA基因表达。肿瘤细胞HLAII类分子表达与CIITA表达一致 ;组成性或诱导性表达CIITA的肿瘤细胞 ,经IFN γ作用后其HLAI、II类分子表达增高 ;IFN γ诱导后仍不表达CIITA的肿瘤细胞 ,其对IFN γ促HLA表达的作用不反应。提示 ,某些肿瘤细胞对IFN γ不能诱导HLA分子表达与CIITA诱导性表达缺陷有关。表面CIITA参与调控肿瘤细胞HLAI、II类分子表达。  相似文献   

5.
为研究恶性肿瘤患者外周血细胞P53(v)表达及其与年龄的关系, 应用FCM检测88例癌症患者外周血细胞中P53(v)的表达. 结果显示, 肿瘤患者外周血细胞P53(v)表达为(7.76±7.13)%, 显著高于对照组的表达(0.66±0.5)%(P<0.01).35.2%的恶性肿瘤患者外周血细胞P53(v)表达≥10%;随年龄增高, 患者血细胞P53(v)表达有增高趋势. 结论: 在肿瘤患者外周血细胞中也能检测出P53(v)表达, 可作为监测和筛选肿瘤高危人群的一个较好的实验室指标.  相似文献   

6.
目的:探讨糖皮质激素诱导的肿瘤坏死因子相关蛋白配体(GITRL)在脂多糖(LPS)诱导的Kupffer细胞(KCs)凋亡中的作用。方法:分离BALB/c小鼠的KCs,转染对照siR-NA或者GITRL siRNA 24 h后,分四组培养,分别为对照(Control)组:仅加入培养液;地塞米松(Dex)组:加入Dex10μmol/L;LPS组:加入LPS 1 mg/L;LPS+Dex组:加入LPS 1 mg/L和Dex 10μmol/L。24 h后用免疫细胞化学法检测GITRL蛋白的表达,应用Annexin V/PI双染标记和流式细胞术检测KCs的凋亡率。结果:LPS刺激增加了KCs GITRL的表达(P<0.05),然而地塞米松处理降低了LPS诱导的GITRL表达。LPS刺激诱导了KCs的凋亡,但是沉默GITRL基因或者地塞米松处理抑制了LPS诱导的凋亡(P<0.05)。结论:LPS可以诱导小鼠KCs的凋亡,其作用可能依赖于GITRL信号的转导。  相似文献   

7.
转移是导致肿瘤患者预后差的根本原因。上皮间质转化( epithehal?mesenchymal transition, EMT)是调控胚胎发生和组织发育过程中细胞形态和功能改变的复杂程序。 EMT在肿瘤转移过程中也起重要作用。已知表观遗传修饰在调控基因表达中起重要作用,其中包括组蛋白甲基化。组蛋白去甲基化酶( his?tone demethylase)可通过特异性的作用于赖氨酸单甲基化、双甲基化和三甲基化调控基因表达。越来越多的研究表明组蛋白赖氨酸去甲基化酶( histone lysine demethylases, KDMs)在调控MET相关基因表达中其重要作用。文章就KDMs在人类恶性肿瘤细胞的EMT过程中的研究进展作一综述。  相似文献   

8.
9.
We revealed activation of apoptotic signal 1-regulating protein kinase, inhibition of poly-(ADP-ribose) polymerase, and intensification of internucleosomal DNA fragmentation in rat liver during oxidative stress induced by cobalt chloride.  相似文献   

10.
目的探讨顺铂(DDP)对MDCK细胞KCa的影响。方法利用内面向外式(inside-out)膜片钳技术。结果(1)在对称性高钾溶液([K ]o:[K ]i=140mmolL-1/140mmolL-1)中,主要记录到电导为51.425±0.570pS(n=5)的外向通道电流,随电压增加而增加。(2)浴液中钾离子浓度由140mmolL-1改变为45mmolL-1,在0mV记录到内向电流,从 30mv开始记录到记录到外向电流,电导为50.385±0.307pS(n=5)。(3)在对称性高钾溶液、膜电位 60mV时;向浴液中加入不同浓度的Ca2 ,从10-7molL-1开始,通道活动浓度依赖性增加。(4)对称性高钾溶液、膜电位为 60mV,向浴液中加入DDP,从1.5×10-5molL-1开始,DDP使通道活性呈现浓度依赖性减少,洗脱后,通道活性部分恢复。结论(1)本实验在MDCK细胞上记录到中电导钙激活钾通道(IKCa),该通道具有电压依赖性和胞内游离Ca2 浓度依赖性,无整流特性。(2)DDP在7.5×10-6molL-1时对KCa没有显著影响;从1.5×10-5molL-1开始使通道活性呈现浓度依赖性减少,减少钾离子外流。  相似文献   

11.
ABSTRACT: Changes in lymphocyte subsets in whole blood of normal pregnant and postpartum women were examined by flow cytometry with an automated leukocyte differential system. From the first trimester and throughout pregnancy, the absolute counts of T(CD3) and B(CD20) and T-cell subsets (CD4, CD8) decreased with a decrease in the absolute lymphocyte count, although the proportions of these cells remained unchanged except for a decrease in the percentage of T helper-inducer (CD4) cells in the first trimester. On the contrary, the percentage of NK/K (Leu 7) cells, but not of NK/K (CD16) cells, increased in the first trimester and then both gradually decreased in the second and third trimesters. In the postpartum period, the percentages and absolute counts of T(CD3) and NK/K (Leu 7) cells, but not of other cells, increased transiently. These changes of lymphocyte subsets may indicate suppression of immunological activity during pregnancy and its “increase” in the postpartum period.  相似文献   

12.
hs-CRP在急性脑梗死患者动态水平及预后的临床意义   总被引:2,自引:0,他引:2  
目的:观察超敏C-反应蛋白(hs-CRP)在脑梗死患者的动态水平与其病情预示作用,了解hs-CRP同脑梗死患者病情关系。方法:收集126例脑梗死患者发病后72h内,第(4—7)d和第14d的血清进行超敏免疫比浊法测定hs-CRP。应用美国国立卫生研究院卒中量表(NIHSS)及Barthel指数(BI)记分法测定神经功能缺损评分。结果:脑梗死后72h血清hs-CRP浓度即开始升高,1周左右达高峰,至14d时接近对照组水平,并发多脏器功能衰竭者CRP水平最高。结论:hs—CRP是判断脑梗死病情轻重和预后的特异性指标,适时终止或减轻炎症反应损害,可以降低脑梗死的病死率及并发多脏器衰竭的危险。  相似文献   

13.
14.
本文应用抗癌基因ras表达产物P21ras蛋白的大鼠单克隆抗体建立的双抗体夹心ELISA法,检测了肝癌及癌病变前病人血清中p21ras蛋白的浓度。所获阳性检出率分别为:慢性乙型肝炎为13.0%(12/92),肝硬化为27.8%(10/36)和肝癌为50.0%(8/16)。另外,对试验方法的敏感性、特异性及稳定性,以及检测P21ras蛋白与AFP的关系进行了评价。结果表明,P21ras蛋白的过高表达发生在肝细胞癌变之前。提示在慢性乙型肝炎及肝硬化病人血清中检出P21ras蛋白,是预测肝细胞癌变的危险信号。  相似文献   

15.
Pahar B  Wang X  Dufour J  Lackner AA  Veazey RS 《Virology》2007,363(1):36-47
CD4(+) T helper and CD8(+) cytotoxic T lymphocyte responses are believed to play an important role in the control of primary HIV and SIV infection. However, the role of these cells in macaques acutely infected with SHIV(sf162p3) has not been well characterized. In this study, ten adult rhesus macaques were intravaginally infected with SHIV(sf162p3), and antigen-specific cytokine responses to SHIV-Tat, Nef, Gag and Env peptide pools were examined through 70 days post inoculation (p.i.) using ELISPOT and/or cytokine flow cytometry (CFC). Peak plasma viral replication occurred between 14 and 21 days p.i. followed by low to undetectable plasma viremia by 70 days of infection in most macaques. Although some animals had strong virus-specific cellular immune responses, many had weak or minimal responses that did not correlate with the post peak decline in plasma viremia.  相似文献   

16.
We developed a highly specific and sensitive polymerase chain reaction (PCR) assay to measure V(D)J recombinase activity using extrachromosomal plasmids and PCR. Extrachromosomal plasmids were prepared by eukaryotic replication origin, and a combination of the DQ52 and JH2 regions of the murine IgH gene, or of the D beta 2-1 and J beta 2.6 regions of the murine TCR beta gene, both with recombination signal sequences. Plasmids, transfected into cells to be examined and recovered after 48 h, were processed to detect recombined molecules by PCR with primers for the expected sequences produced by the precise signal joint. The PCR assay, when compared with a Camr assay that we prepared with the DQ52 and JH2 regions of the murine IgH gene, seems to have the following advantages. It detects only the recombined products produced by V(D)J recombinase activity and is therefore highly specific. It detects V(D)J recombinase activity in cells, including those with low replication frequency, which our Camr assay failed to do. This also enables detection of the recombinase activity not only in murine cell lines, but also in cells of murine lymphoid organs. The assay detects V(D)J recombinase activity in cell lines of human origin by replacing the eukaryotic replication origin of plasmids. High V(D)J recombinase activity was detected in bone marrow cells followed by thymic cells, and apparently lower activity was detected in cells of the lymph node and spleen of normal mice.  相似文献   

17.
Raji-cell radioimmunoassay is a very sensitive and reproducible method for the detection of circulating immune complexes. Using a complement-independent, antibody-dependent cellular cytotoxicity assay against51Cr-labeled Raji cells, there is no correlation between activity against Raji cells and positivity in Raji-cell radioimmunoassay for circulating immune complexes in three sets of sera (from renal transplantation patients, multiparous women, and patients suffering from systemic lupus erythematosus). We conclude that IgG antibodies to Raji membranes are not a significant cause of false-positive results in circulating immune complexes as detected by Raji-cell radioimmunoassay.  相似文献   

18.
目的:探讨了脑梗死患者治疗前后血清GM—CSF和血小板α-颗粒膜蛋白(PGMP)水平的变化及意义。方法:应用放射免疫分析对36例脑梗死患者进行了血清GM—CSF和PGMP水平测定,并以30例正常健康人作比较。结果:在治疗前血清GM—CSF和PGMP水平均非常显著地高于正常人组(P〈0.01),经治疗后6个月与正常人比较仍有显著差异(P〈0.05)。结论:脑梗死的发生、发展与血清GM—CSF和PGMP水平密切相关。  相似文献   

19.
A number of antibodies to neural proteins have been used to demonstrate neuronal differentiation in primitive neuroectodermal tumours. One of them is protein gene product (PGP) 9.5, a neuronal protein isolated from brain, whose function is unknown at present. We have studied differentiation in 21 cases of primitive neuroectodermal tumours of the CNS in children. Immunocytochemical staining was performed for such neuronal markers as: PGP 9.5, neuron specific enolase and synaptophysin, a glycosylated protein associated with synaptic vesicles. Positive staining for PGP 9.5 was present in 16 cases (strong staining in 12), for neuron-specific enolase in 16 cases (strong staining in 10) and for synaptophysin in 10 cases (strong staining in six). Both PGP 9.5 and synaptophysin showed a clear staining pattern with less non-specific background than with neuron-specific enolase. Our findings demonstrate the value of using more than one antibody marker in assessing neuronal differentiation in tumours. The high incidence of positive staining with antibody to PGP 9.5 suggests that this is an essential marker in the panel of antibodies used for the identification of primitive neuroectodermal tumours.  相似文献   

20.
目的:探讨了冠心病患者血清超敏C反应蛋白(hs-CRP)和E-选择素(E-Selectin)水平的变化及意义.方法:应用免疫比浊法检测hs-CRP,ELISA法检测E-Selectin水平对58例冠心病患者进行了血清hs-CRP,E-Selectin水平检测.其中稳定型心绞痛25例,不稳定型心绞痛20例,急性心肌梗死13例,并以35名正常健康人作比较.结果:冠心病患者血清hs-CRP和E-Selectin水平明显高于正常人组(P<0.01),急性心肌梗死组和不稳定型心绞痛组有明显高于稳定型心绞痛组(P<0.01),冠心病组血清hs-CRP、E-Selectin水平与冠状动脉狭窄程度无明显相关性(P>0.05).结论:血清hs-CRP和E-Selectin水平的变化与冠心病的发生、发展有关,但与冠状动脉狭窄程度无关.  相似文献   

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