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唐永明  张斌 《江苏医药》1997,23(12):833-835
采用ABC免疫组化染色法及单克隆抗体夹心法ELISA,同步检测了34例肾综合征出血热(HFRS)患者外周血T细胞亚群数量和血清白细胞介素2和4(IL-2、IL-4)水平。发现HFRS病程中各T细胞亚群数量均有不同程度的升高,其中CDS阳性T细胞在各病期均有升高。IL-4水平升高仅见于发热期.而IL-2的升高主要在低血压期和少尿期。病程中有CD4/CD8比值的下降甚至倒置。这种比值的变化与IL-2和IL-4的动态变化有一定的相关性。结果揭示,在HFRS发病机理中存在Thl型和Th2型免疫反应等多种免疫病理机制。  相似文献   
3.
Lymphocytes continuously migrate through the body, and their efficient extravasation from the blood via high endothelial venules (HEV) is essential for initiating an appropriate immune response. Most investigations have focused on the lymphocyte/HEV interaction in vitro. However, to what extent such systems reflect the situation in vivo is not known. It is also unclear whether lymphocyte subsets immigrate into the HEV in proportion to their presence in the blood, and whether import capacity is limited by the HEV. When rat mesenteric lymph node lymphocytes were incubated in vitro on cryostat sections, the well-known preferential binding of B lymphocytes to HEV of Peyer's patches (PP) and T cells to HEV of axillary lymph nodes (axLN) was observed (axLN vs. PP: B lymphocytes 21.2 ± 5.0% vs. 40.6 ± 11.0%, T lymphocytes 84.6 ± 6.3% vs. 56.5 ± 12.9%). However, when labeled mesenteric lymph node lymphocytes were injected and their location within the HEV was analyzed 15 min later, no preferential interaction was seen. After injection of labeled thoracic duct lymphocytes, the percentage of labeled cells among B and T lymphocytes in the blood was significantly different (4.4 ± 0.9% vs. 8.9 ± 3.6%), whereas that in HEV of axLN (19.0 ± 6.4% vs. 16.6 ± 6.0%) and PP (30.6 ± 6.1% vs. 33.9 ± 4.4%) was comparable. Although the number of injected lymphocytes was similar in magnitude to the total blood lymphocyte pool, after injection there was no increase in lymphocyte numbers in the HEV. Thus, the adhesion assay in vitro does not completely reflect immigration into HEV in vivo. In addition, our data suggest that both the availability of lymphocyte subsets in small venules and the immigration rate into HEV are actively regulated in vivo.  相似文献   
4.
The in vitro proliferation of peripheral blood lymphocytes (PBLs) without any mitogenic stimulation is one of the hallmarks of human T lymphotropic virus type I (HTLV-I) infection. Recent evidence suggests a difference in the degree of the phenomenon between HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and asymptomatic HTLV-I carriers (AC). In this article, we demonstrated several alterations in the features of the in vitro transformed lymphocytes between patients with HAM/TSP (n = 16) and AC (n = 8). The percentages of total CD8+ and CD8+CD28+ cells were significantly increased in the in vitro proliferating T lymphocytes derived from the patients with HAM/TSP when compared to those from AC. HAM/TSP was segregated from AC by the high degree of the proliferation of CD8+CD28+ cells. The expression of HTLV-I-specific antigens on the cultured PBLs was detected only in the subjects which showed low CD8+CD28+/CD4+ ratio of the in vitro proliferating lymphocytes. These findings suggest that this phenomenon distinguishes HAM/TSP from AC, not only in quantity but also in quality.  相似文献   
5.
Prostaglandin E1 (PGE1) was used in renal transplant recipients with living related donors. The drug was given intravenously from day 1 to day 7 after transplantation at a dose of 40 µg/kg twice a day. A total of 45 patients were studied divided into two groups: 25 patients were treated with PGE1 (group B) and the remaining 20 patients did not receive the drug (group A). In group B, 24-h creatinine clearance (Ccr) was 66 ± 12.8 ml/min compared with 40.3 ± 13.4 ml/min in group A on the fifth postoperative day (P < 0.05). Urinary levels of N-acetyl-β-d -glucosaminidase (NAG) and serum levels of platelet factor 4 (PF4) in group B were significantly lower than in group A. On the fourth postoperative day, the urinary excretion of thromboxan B2 (TxB2) in group A was higher than in group B, but not significantly (5.1 ± 3.0 ng/day and 2.8 ± 1.1 ng/day, respectively). Acute rejection occurred in four patients in group B and in 10 patients (40%) in group A. The percentage of Leu2a-positive lymphocytes in group B was higher than in group A. We conclude that postoperative administration of PGE1 improves graft function in kidneys from living related donors.  相似文献   
6.
目的探讨麻风病患者外周血相关免疫分子的变化和临床意义。方法应用流式细胞分析仪,以荧光标记的鼠抗人单克隆抗体对16例麻风病患者外周血淋巴细胞CD3/CD4/CD8、CD3/CD(16 56)(NK)和CD3/HLA-DR进行测定。结果16例患者发病初期外周血淋巴细胞亚群中CD3^ /CD4^ 、CD3^ /HLA-DR^-检测值和CD4/CD8比值均分别低于健康组相应参数的下限,CD3^ /CD(16 56)^ 和CD3^ /HLA-DR^ 检测值分别高于健康组相应参数的上限、NK的检测值在正常范围内。13例患者治疗病情稳定后2-4周,CD3^ /CD4^ 、CD3^ /HLA-DR^-的检测值和CD4/CD8比值均逐步增高,CD3^ /CD(16 56)^ 、CD3^ /CD8^ 和CD3^ /HLA-DR^ 稍有增高或变化不明显,NK的检测值稍有增高;3例患者病情波动时CD3^ /CD4^ 、CD3^ /HLA-DR^-检测值和CD4/CD8比值较稳定期明显下降,而活化T淋巴细胞CD3^ /CD(16 56)^ 、CD3^ /HLA-DR^ 和NK细胞的检测值较稳定期明显增高2倍以上。结论通过外周血相关免疫分子的动态观察,有助于检测病情变化,时及时治疗和评价疗效有重要意义。  相似文献   
7.
脂肪干细胞免疫学性状的初步实验观察   总被引:3,自引:0,他引:3  
目的初步研究脂肪干细胞(Adiposederivedstemcells,ADSC)表面免疫分子的表达以及体外免疫调节功能,以期为组织工程提供同种异体种子细胞来源。方法体外培养人脂肪抽吸术中获取的脂肪干细胞,体外培养至第二代,流式细胞仪检测免疫分子HLA、HLA、B7-1、B7-2、CD40的表达。1×105个/孔ADSC细胞分别刺激单一异体淋巴细胞或混合双向淋巴细胞反应,观察淋巴细胞增殖情况。同时观察ADSC经IFN-γ作用后,免疫分子表达与淋巴细胞增殖的调节情况。结果ADSC表达HLA类分子,但未检测到HLA类分子阳性表达。B7-1(CD80)、B7-2(CD86)、CD28、CD40未见明显阳性表达。人IFN-γ刺激48h后,HLA类分子表达明显增高,HLAI表达未见明显增高。异体或经IFN-γ作用的ADSC均未能刺激异体淋巴细胞增殖。同样数量的ADSC可明显抑制双相混合淋巴细胞增殖,经IFN-γ作用后抑制作用未见明显减弱。结论ADSC具有一定的体外调节淋巴细胞反应的能力,有可能成为组织工程同种异体细胞来源。  相似文献   
8.
Using experimental autoimmune encephalomyelitis (EAE) in the rat as a model of central nervous system (CNS) inflammation, activated and quiescent T lymphocytes with different antigen specificities were labelled with the fluorescent dye Hoechst 33342 and tested by fluorescence microscopy for their ability to accumulate in different regions of the spinal cord and in other organs at varying times post inoculation. With this highly sensitive assay it was found that activated myelin basic protein (MBP)-specific T cell lines accumulated in the spinal cord (a 1000-fold increase in the lumbar/sacral region by day 4) and caused clinical signs of EAE. In contrast, interleukin-2 (IL-2)-maintained (quiescent) MBP-specific T cell lines failed to accumulate in the CNS and cause disease. Activated ovalbumin (OA)-specific and purified protein derivative of tuberculin (PPD)-specific T cell lines were also found at significantly higher levels in the spinal cord than non-activated cells although they failed to accumulate to a substantial degree when injected alone. When injected with activated MBP-specific T cells the activated OA- and PPD-specific cell lines accumulated in the spinal cord following initial accumulation of the MBP-specific cells, demonstrating that during the inflammatory process there is considerable non-specific recruitment of cells into the inflammatory site. CNS accumulation of activated MBP-specific T cell lines occurred 1-2 days later in irradiated animals than in non-irradiated recipients. This was consistent with irradiated animals also exhibiting a later onset of disease and suggests that irradiation may directly affect the endothelium in a way that makes it less adhesive. In conclusion, this study demonstrates that activated lymphocytes of any specificity enter the spinal cord, and that the neuro-antigen specific cells accumulate there and lead to the recruitment of other cells. Non-activated cells, even those with neural antigen specificity fail to enter the cord. Understanding the nature of what an 'activated' lymphocyte is may allow us to design strategies to inhibit such immune-mediated inflammation.  相似文献   
9.
Vasoactive intestinal peptide (VIP) is a neuropeptide which also interacts with cells of the immune system. The paucity of specific VIP receptor antagonists has hampered studies of possible receptor heterogeneity and of VIP function. To aid in achieving these goals, a new VIP antagonist, a hybrid between neurotensin and VIP, has been synthesized. This peptide interacted with VIP receptors on spinal cord cells with an affinity 10-fold greater than VIP itself. In contrast, 1000-fold higher concentrations of the antagonist were required to displace labeled VIP from its receptor on lymphoid cells as compared to VIP itself, suggesting VIP receptor heterogeneity between immune and spinal cord cells.  相似文献   
10.
老年人生理适应与防卫能力进行性下降,对有害因子易伤性增加,导致多种老年病的发生。因此,免疫系统功能与衰老的关系问题,已是现代老年病学和免疫学进行多方深入研究的重要内容。我们近两年多来对老年人免疫功能变化做了临床观察检测与统计分析。现报告如下。 1.临床资料  相似文献   
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