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61.
目的 建立一个在胸腺内表达外源性主要组织相容性抗原复合体(MHC)抗原的实验模型,为下一步研究作准备。方法 应用逆转录病毒载体介导的基因转移技术,首次将外源性MHC基因转移到T淋巴表达并应用聚合酶链反应(PCR)及反转录聚合酶链反应(RT-PCR)检测转染T细胞DNA及mRNA。结果 外源性MHC基因已整合到靶细胞染色体DNA并有效地转录;单克隆抗体免疫荧光染色流式细胞仪检测显示在转染T细胞膜有外源性MHC分子表达;转染效率为46.2%。结论 外源性MHC基因可以转移到T细胞稳定表达,为今后的研究提供了经验。 相似文献
62.
C. L. R. BARRATT P. E. HARRISON A. ROBINSON I. D. COOKE 《International journal of andrology》1990,13(1):50-58
The significance of white blood cells in the ejaculate remains a matter of controversy. Several authors have suggested that such cells are important in the modulation of an antisperm antibody response, i.e. a predominance of suppressor/cytotoxic to helper/inducer T cells may prevent the development of antisperm antibodies. In order to examine this relationship further we have documented the white blood cell types, with emphasis on the T-lymphocyte populations, in the ejaculates of men from infertile couples with and without antisperm antibodies; the latter group was divided further into two groups--vasovasostomized men and idiopathic men. All seven of the men without antisperm antibodies had a predominance of suppressor/cytotoxic T cells to helper/inducer T cells in the ejaculate. However, only in some of the men with antibodies was there a predominance of T-helper/inducer cells. It is clear that the relationship between antisperm antibodies and seminal leucocytes is therefore not as straightforward as has been proposed. 相似文献
63.
Intestinal intraepithelial lymphocytes (iIEL) are primarily CD8 cells and most of them have a CD28? phenotype, the phenotype of effector cytotoxic T cells. We asked whether the predominance of CD8+ CD28? T cells in the gut may result from peripheral blood T cells preferentially migrating to the iIEL compartment and adhering to iEC. Compared with CD4 cells, adhesion of resting CD8+ T cells to iEC cell lines was significantly higher. Adhesion could be blocked with a MoAb to gp180, a molecule expressed on iEC which is known to interact with CD8/lck. No significant difference in the level of adhesion was observed between CD8+ CD28+ and CD8+ CD28? T cells. Thus CD8 cells may preferentially migrate to the iIEL compartment, but loss of CD28 expression could occur in situ after migration. Consistent with this hypothesis, the CD8+ CD28? cells became enriched after co-culturing T cells with iEC cell lines and primary iEC. Induction of the CD8+ CD28? phenotype in cord blood and adult T cells was observed in co-cultures with iEC and also with mitogens and superantigens. In the latter case, CD28 down-modulation was seen specifically in the Vβ subset targeted by the superantigen, indicating that loss of CD28 expression is a direct result of T cell receptor (TCR)-mediated stimulation. The combined results suggest that CD8+ CD28? T cells are antigen experienced T cells, and that they may have a survival advantage in the presence of gut epithelial cells in vitro. This may contribute to the predominance of CD8+ CD28? T cells in the iIEL compartment. 相似文献
64.
本文对28例小儿病毒性心肌炎患者进行了T细胞检测,发现患儿外周血T细胞亚群有明显改变。提示:小儿病毒性心肌炎患者均有不同程度的一过性细胞免疫功能低下。而体液免疫功能正常,我们在临床给与一般治疗的同时,佐以胸腺因子治疗,明显改善症状,取得良好疗效。 相似文献
65.
以聚合酶链反应(PCR)法在mRNA水平检测T淋巴细胞受体α链可变区基因表达为例,介绍用~(32)P标记的人工合成寡核苷酸探针对PCR产物特异性作阳性证实的方法。该法以干琼脂糖凝胶作为支持物、相对较为简便和省财。用Ca探针以干凝胶作支持物的杂交结果,证实29个Vα基因的PCR扩增中物均为特异性的,放射自显影的带型与位置和溴乙锭染色所示完全吻合。 相似文献
66.
M. Ohshima A. Yokoyama H. Ohnishi H. Hamada N. Kohno J. Higaki T. Naka 《Clinical and experimental allergy》2007,37(5):735-742
BACKGROUND: Enhanced expression of the suppressor of cytokine signalling (SOCS)-5 might be of therapeutic benefit for T-helper type 2 (Th2) dominant diseases, as its expression is reported to result in a reduction of Th2 differentiation in vitro due to the inhibition of IL-4 signalling. OBJECTIVE: To investigate the regulatory role of SOCS-5 in vivo, we explored the phenotype of an experimental asthma model developed in SOCS-5 transgenic (Tg) mice. METHODS: The SOCS-5 Tg mice or wild-type (WT) mice were sensitized and repeatedly challenged with ovalbumin (OVA). We examined bronchoalveolar lavage fluid (BALF), lung specimens, and airway hyperresponsiveness (AHR) to methacholine. RESULTS: The production of IFN-gamma by CD4(+) T cells from unprimed SOCS-5 Tg mice was significantly increased in comparison with unprimed wild-type mice, indicating that SOCS-5 Tg mice have a Th1-polarizing condition under natural conditions. However, in an asthma model, significantly more eosinophils in the airways and higher levels of IL-5 and IL-13 in BALF were observed in the SOCS-5 Tg than the wild-type mice. AHR in the asthma model of SOCS-5 Tg was also more enhanced than that of wild-type mice. OVA-stimulated CD4(+) T cells from the primed SOCS-5 Tg mice produced significantly more IL-5 and IL-13 than CD4(+) T cells from wild-type mice. CONCLUSION: Our results demonstrate that the overexpression of SOCS-5 does not inhibit Th2 response, but rather augments the phenotype of the asthma model in vivo. This finding throws into question the therapeutic utility of using enhancement of SOCS-5 expression for Th2-dominant disease. 相似文献
67.
再生障碍性贫血造血细胞Fas抗原表达与T淋巴细胞功能的研究 总被引:1,自引:0,他引:1
目的 研究造血细胞凋亡与T淋巴细胞免疫在再生障碍性贫血(再障,Aplastic anemia,AA)发病机制中的作用及两者相关性。方法 采用流式细胞仪测定40例AA患者和15例非血液、免疫系统疾病对照者骨髓单个核细胞(BMMNC)的总CD34^ 、CD34^ Fas^ 、CD34^ Fas^-、CD3^ 、CD8^ 、CD3^ 、CD3^ CD25^ 标记值。结果 (1)与对照组比较,AA组总CD34^ 细胞%明显减少而其Fas表达率(以占总CD34^ 细胞%为计)明显增高。(2)AA组CD34^ 细胞%数与其Fas抗原表达率无明显负相关。(3)AA组T细胞%明显增多,且以CD8^ 细胞和CD3^ CD25^ 细胞增多为主。(4)AA组CD34^ 细胞%数与其T细胞活化状态无显著负相关。(5)AA组CD34^ 细胞Fas表达率与其T细胞活化状态无显著正相关。结论 AA骨髓存在着造血细胞数量减少和T淋巴细胞亚群数量、功能的异常,造血细胞数量减少还可能与Fas以外途径诱导的凋亡过度有关。骨髓造血细胞凋亡过度可能有活化T淋巴细胞免疫以外的途径诱导Fas途径或活化T淋巴细胞可以通过Fas之外的途径诱导造血细胞凋亡。 相似文献
68.
The effect of the barbiturate T2000 (1,3-dimethoxymethyl-5,5-diphenyl-barbituric acid; DMMDPB) on essential tremor, given in twice daily doses of 400 and 300 mg, was assessed in two brief, randomized, placebo-controlled, parallel-group, double-blinded, single-center trials in 12 and 22 patients, respectively. These trials represent the first clinical use of T2000 for a specific indication. The primary endpoint was the change in the mean scores of the treated and control groups based on the Fahn-Tolosa-Marin tremor scale. In the first study of 12 patients treated with 400 mg or placebo twice daily for 14 days, the mean change from baseline at day 14 was 19.3 (P < 0.0001) in the treated group and 9.0 (P = 0.0121) in the control group. Using a two-factor mixed ANOVA model to evaluate within group and between group changes, the effect of T2000 was significantly different from that of the placebo group (P = 0.03). In the second study of 22 patients treated with 300 mg of T2000 or placebo twice daily for 20 days, statistically significant changes were seen in treated patients compared to baseline, but the ANOVA model did not demonstrate a significant treatment effect of T2000 compared to placebo. When the treated groups from each study are compared, the 800-mg daily group is significantly different from the 600-mg daily group (P = 0.02). Some treated patients in each study, but no placebo patients, experienced marked improvement. These results support further evaluation of T2000 in the treatment of essential tremor. 相似文献
69.
目的 探讨喉癌局部组织的细胞免疫状态与前列腺素类物质前列环素及血栓素的关系。方法 应用免疫组化法检测了28例喉鳞癌患者局部组织内淋巴细胞亚群的分布状况,并与该患者残喉健康侧组织及喉良性肿瘤患者的瘤组织进行对比;同时采用放射免疫分析法分别检测了上述喉鳞癌、喉良性肿瘤患者和正常人血浆前列环素(PGI2)及血栓素A2(TXA2)的含量,并以它们在健康人血浆中的含量为正常对照。结果 喉癌组织内浸润的CD4和CD8细胞数明显升高,而且CD8细胞多于CD4细胞,提示喉癌组织局部的细胞免疫功能受抑。同时喉癌患者血浆中PGI2和TXA2的稳定代谢产物6-酮-前列腺素F1α及血栓素B2(TXB2)的含量高于正常对照组,以TXB2升高更明显。结论 喉癌患者体内前列腺素类物质PGI2/TXA2与其癌组织局部细胞免疫受抑有关,因而可作为生物学标记提示喉癌组织局部的细胞免疫功能状态。 相似文献
70.
Reto Treier Andreas Steingoetter Michael Fried Werner Schwizer Peter Boesiger 《Magnetic resonance in medicine》2007,57(3):568-576
Fast T(1) mapping techniques are a valuable means of quantitatively assessing the distribution and dynamics of intravenously or orally applied paramagnetic contrast agents (CAs) by noninvasive imaging. In this study a fast T(1) mapping technique based on the variable flip angle (VFA) approach was optimized for accurate T(1) quantification in abdominal contrast-enhanced (CE) MRI. Optimization methods were developed to maximize the signal-to-noise ratio (SNR) and ensure effective RF and gradient spoiling, as well as a steady state, for a defined T(1) range of 100-800 ms and a limited acquisition time. We corrected B(1) field inhomogeneities by performing an additional measurement using an optimized fast B(1) mapping technique. High-precision in vitro and abdominal in vivo T(1) maps were successfully generated at a voxel size of 2.8 x 2.8 x 15 mm(3) and a temporal resolution of 2.3 s per T(1) map on 1.5T and 3T MRI systems. The application of the proposed fast T(1) mapping technique in abdominal CE-MRI enables noninvasive quantification of abdominal tissue perfusion and vascular permeability, and offers the possibility of quantitatively assessing dilution, distribution, and mixing processes of labeled solutions or drugs in the gastrointestinal tract. 相似文献