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21.
用体外培养人角朊细胞研究了1.25-双羟维生素D_3(1,25(OH)_2D_3)对角朊细胞增殖,细胞形态及HLA-DR,ICAM-1分子表达的影响,培养液中加入1,25(OH)_2D_3可使细胞增殖明显抑制。用流式细胞仪测定,1,25(OH)_2D_3处理6天后角朊细胞体积较未处理的明显变大。用免疫组化染色显示1,25(OH)_2D_3对经IFN-γ和TNFa刺激的角朊细胞HLA-DR和ICAM-1分子表达无明显影响。  相似文献   
22.
Summary We investigated the effects of recombinant human gamma interferon on the induction of HLA-DR expression by two human squamous cell carcinoma, three trichilemmoma, one eccrine carcinoma, two adenocarcinoma cell lines, and cultured human keratinocytes in vitro. None of eight epithelial cell lines or keratinocytes expressed HLA-DR without gamma interferon treatment. In contrast, pure gamma interferon (500 IU/ml, 72-h treatment) induced HLA-DR expression on 1/2 squamous cell carcinoma, 3/3 trichilemmoma, 2/2 adenocarcinoma cell lines, and 4/4 kerationcyte cell lines, as determined using a fluorescence-activated cell sorter. A maxillary squamous cell carcinoma line and an eccrine carcinoma cell line failed to express HLA-DR with gamma interferon treatment; however, the growth of cells was inhibited by gamma interferon treatment. By indirect immunoperoxidase techniques, tumor cells such as Bowen's disease and squamous cell carcinoma were found to express HLA-DR. Since HLA-DR expression has been shown to be important for various immune responses, these findings suggest that gamma interferon plays important roles in various immune-related skin diseases.  相似文献   
23.
用生物素-链霉亲和素系统免疫细胞化学和流式细胞仪检测mIL-2R和HLA作为考核胸腺肽体外活性的指标,结果表明,25~100μg/ml胸腺肽在体外明显提高mIL-2R和HLA-DR表达率,提示胸腺肽具有激活淋巴细胞的功能,为胸腺肽治疗慢性肝炎的机理提供了理论基础。  相似文献   
24.
Background and aimPatients with systemic lupus erythematosus (SLE) have a higher prevalence of subclinical atherosclerosis and higher risk of cardiovascular (CV) events compared to the general population. The relative contribution of CV-, immune- and disease-related risk factors to accelerated atherogenesis in SLE is unclear.Methods and resultsFifty SLE patients with long-lasting disease (mean age 44 ± 10 years, 86% female) and 50 sex- and age-matched control subjects were studied. Common carotid artery intima-media thickness (CCA-IMT) was used as a surrogate marker of atherosclerosis. We evaluated traditional and immune- and disease-related factors, assessed multiple T-cell subsets by 10-parameter-eight-colour polychromatic flow cytometry and addressed the effect of pharmacological therapies on CCA-IMT. In SLE patients, among several cardiometabolic risk factors, only high-density lipoprotein levels (HDL) and their adenosine triphosphate-binding cassette transporter 1 (ABCA-1)-dependent cholesterol efflux capacity were markedly reduced (p < 0.01), whereas the CCA-IMT was significantly increased (p = 0.03) compared to controls. CCA-IMT correlated with systolic blood pressure, low-density lipoprotein (LDL) cholesterol and body mass index (BMI), but not with disease activity and duration. The activated CD4+HLA-DR+ and CCR5+ T-cell subsets were expanded in SLE patients. Patients under hydroxychloroquine (HCQ) therapy showed lower CCA-IMT (0.62 ± 0.08 vs. 0.68 ± 0.10 mm; p = 0.03) and better risk-factor profile and presented reduced circulating pro-atherogenic effector memory T-cell subsets and a parallel increased percentage of naïve T-cell subsets.ConclusionHDL represents the main metabolic parameter altered in SLE patients. The increased CCA-IMT in SLE patients may represent the net result of a process in which ‘classic’ CV risk factors give a continuous contribution, together with immunological factors (CD4+HLA-DR+ T cells) which, on the contrary, could contribute through flares of activity of various degrees over time. Patients under HCQ therapy present a modified metabolic profile, a reduced T-cell activation associated with decreased subclinical atherosclerosis.  相似文献   
25.
背景:有文献报道,肝移植后受者外周血淋巴细胞的变化较肝脏酶学的改变更为敏感,其特异性有待进一步研究.目的:分析淋巴细胞亚群中CD3/HLA-DR+,CD3+/CD25+和CD3+/HLA-DR-与肝移植受者机体免疫状况和并发症的关系.方法:应用全自动生化分析仪和流式细胞分析仪检测56例肝移植受者移植后肝功能和淋巴细胞亚群,依照肝功能情况划分为肝功能正常组52例和肝功能异常组27例,肝功能异常组中分为急性排斥组7例、药物反应组1 1例和原因不明组9例.分析各组肝移植受者CD3-/HLA-DR+,CD3+/CD25+和CD3+/HLA-DR.表达水平与其并发症的关系.结果与结论:肝功能正常组CD3-/HLA-DR+和CD3+/CD25+的表达水平低于肝功能异常组(p=0.011,0.002),CD3+/HLA-DR-的表达高于肝功能异常组(p=0.012).CD3-/HLA-DR+和CD3+/CD25+在急性排斥组的表达水平明显高于药物反应组(P=0.039,0.048),急性排斥组CD3+/HLA-DR-的表达水平低于药物反应组(p=0.007).提示CD3-/HLA-DR+,CD3+/CD25+和CD3+/HLA-DR.的表达水平与肝移植后受者机体免疫状况及并发症密切相关,可作为判断肝移植后受者并发症的辅助指标以及进行免疫干预的参考依据.  相似文献   
26.
Li X  Li R  Li Z 《Tissue antigens》2006,67(1):45-52
Collagen (CII) 263-272 peptide, an autoantigen in rheumatoid arthritis, is a specific human leukocyte antigen (HLA)-DR1/4-binding peptide recognized by T-cell receptors (TCR). The affinity of influenza virus haemagglutinin (HA) 306-318 peptide for the antigen-binding groove of HLA-DR1/4 molecules is higher than that of CII263-272. The HLA-DR1/4-binding residues of HA306-318 are located in the region 308-317. Altered HA308-317 peptides with substitutions of TCR-contact residues may inhibit HLA-DR1/4-specific T-cell activation by blocking the antigen-binding site of HLA-DR1/4 molecules. To evaluate the role of altered HA308-317 peptides in HLA-DR1-restricted T-cell activation, we synthesized three altered HA308-317 peptides. The specific binding of altered HA308-317 peptides to HLA-DR1 molecules was examined using flow cytometry. Effects of altered HA308-317 peptides on HLA-DR1-specific T-cell hybridoma were studied by measuring T-cell proliferation and surface expression of CD69 or CD25. The results showed that altered HA308-317 peptides were able to bind to HLA-DR1 molecules and competed with CII263-272 or wildtype HA308-317 peptide. Compared with wildtype CII263-272 or HA308-317, altered HA308-317 peptides did not stimulate significant T-cell proliferation and CD69 or CD25 expression. Furthermore, the altered HA308-317 peptides inhibited HLA-DR1-specific T-cell activation induced by CII263-272 or wildtype HA308-317 peptide, which may suggest an effective therapeutic strategy in inhibition of HLA-DR1-specific T-cell responses in autoimmunity.  相似文献   
27.
Staphylococcus aureus may perform an crucial function in atopic dermatitis (AD), via the secretion of superantigens, including staphylococcal enterotoxins (SE) A or B, and toxic shock syndrome toxin-1 (TSST-1). Dysregulated cytokine production by keratinocytes (KCs) upon exposure to staphylococcal superantigens (SsAgs) may be principally involved in the pathophysiology of AD. We hypothesized that lesional KCs from AD may react differently to SsAgs compared to nonlesional skin or normal skin from nonatopics. We conducted a comparison of HLA-DR or CD1a expression in lesional skin as opposed to that in nonlesional or normal skin by immunohistochemistry (IHC). We also compared, using ELISA, the levels of IL-1alpha, IL-1beta, and TNF-alpha secreted by cultured KCs from lesional, nonlesional, and normal skin, after the addition of SEA, SEB and TSST-1. IHC revealed that both HLA-DR and CD1a expression increased significantly in the epidermis of lesional skin versus nonlesional or normal skin in quite a similar manner. IL-1alpha, IL-1beta, and TNF-alpha secretion was also significantly elevated in the cultured KCs from lesional skin after the addition of SsAgs. Our results indicated that KCs from lesional skin appear to react differently to SsAgs and increased proinflammatory cytokine production in response to SsAgs may contribute to the pathogenesis of AD.  相似文献   
28.
目的:构建能抑制MHC—Ⅱ类分子表达的MHC—Ⅱ类分子反式激活因子(MHC class Ⅱ transactivator,CⅡTA)基因的突变体.并探讨其抑制MHC—Ⅱ类分子表达的机制。方法:用PCR、酶切及连接技术,构建不含起始密码子的pcDNA3mCⅡTA2,含起始密码子的pcDNA3mCⅡTA3以及含起始密码子及NLS(nuclear localization signal)的pcDNA3mCⅡTA4突变体。用脂质体转染法,将上述3种突变体及空载体pcDNA3转入Hela细胞和Raji细胞中。用流式细胞术和RT-PCR法,观察他们对Hela/Raji细胞HLA—DR/DQ分子的诱导性和组成性表达的影响。将mCⅡTA4转移到对四环素浓度依赖的质粒pU-HD10-3上,通过改变培养环境中四环素的浓度,调节外源CⅡTA突变体的表达量,观察突变体的表达量与MHC-Ⅱ类分子受抑率的关系。结果:细胞和基因水平证实,pcDNA3mCⅡTA3和pcDNA3mCⅡTA4对Hela/Raji细胞HLA-DR/DQ的表达均有明显的抑制作用;而pcDNA3mCⅡTA2和空载体pcD-NA3无此作用。MHC-Ⅱ类分子被抑制的程度与外源转入CⅡTA突变体(pUHD10-3mCⅡTA4)的量明显相关。结论:成功地构建pcDNA3mCⅡTA3和pcDNA3mCⅡTA4,并能抑制HLA-Ⅱ类分子的表达。初步证实CⅡTA突变体是通过与胞内的野生型CⅡTA竞争性结合反式激活蛋白,来抑制MHC-Ⅱ类分子的转录和表达。  相似文献   
29.
目的研究昆明白族和彝族儿童HLA-DRB1/DQB1等位基因多态性,分析比较昆明白族和彝族人群的遗传特点。方法采用PCR-SSP基因分型技术,分别对70名白族儿童和70名彝族儿童进行HLA-DRB1/DQB1基因分型。结果昆明白族儿童在HLA-DRB1位点上共检出13种等位基因,依次为DRB1*08(20.7%)、*04(16.4%)、*12(16.4%)、*15(8.57%)、*0901(8.57%)、*14 (6.43%)、*11(5.71%)、*16(5.00%)、*13(4.29%)、*07(2.86%)、*03(2.86%)、*01 (1.43%)、*10(0.71%);HLA-DQB1位点上共检出7种等位基因,依次为DQB1*0301(23.6%)、*06(21.4%)、*05(18.6%)、*04(18.6%)、*0303(7.14%)、*0302(6.43%)、*0201(4.29%)。彝族儿童在HLA-DRB1位点上共检出12种等位基因,依次为DRB1*12(33.57%)、*0901 (11.43%)、*04(11.43%)、*01(8.57%)、*11(7.86%)、*14(7.14%)、*15(7.14%)、*08 (5.00%)、*03(2.83%)、*13(2.14%)、*07(1.43%)、*16(1.43%);HIA-DQB1位点上共检出7种等位基因,依次为DQB1*0301(45%)、*05(22.14%)、*0303(12.14%)、*04(6.43%)、*06 (6.43%)、*0201(4.29%)、*0302(3.57%)。组间比较HLA-DRB1/DQB1等位基因总体分布及诸多等位基因频率均有显著差异。结论昆明白族和彝族人群HLA-DRB1/DQB1等位基因分布具有各自遗传特点。  相似文献   
30.
Migration through basement membrane modulates eosinophil expression of CD44   总被引:2,自引:0,他引:2  
BACKGROUND: Tissue eosinophils express more membrane receptors and release more mediators than blood eosinophils, suggesting that migration from blood to tissue modulates eosinophil phenotype and functions. OBJECTIVE: We postulated that eosinophil passage through endothelial basement membrane, an important step of eosinophil migration into tissue, may be responsible for some of these changes. METHOD: We previously showed that 5-oxo-6, 8, 11, 14-eicosatetraenoic acid (5-oxo-ETE) in combination with IL-5 promotes eosinophil migration through Matrigel, a mouse tumour cell-derived basement membrane. Using this model, we evaluated the effect of trans-Matrigel migration on purified human blood eosinophil expressions of CD44, CD69 and HLA-DR that either increase or appear on activated eosinophils, and releases of peroxidase (EPO), leukotriene (LT) C(4) and granulocyte-monocyte colony stimulating factor (GM-CSF). RESULTS: IL-5, but not 5-oxo-ETE, increased eosinophil expression of CD44 and CD69. Migration of eosinophils through Matrigel significantly increased CD44 expression level over the one induced by IL-5 (P = 0.0001). Migration through Matrigel did not modify CD69 expression compared with the one obtained in the presence of IL-5 alone; however, incubation of eosinophils on Matrigel decreased IL-5-induced CD69 (P = 0.0001). Trans-Matrigel migration did not modify HLA-DR expression, nor EPO, LTC(4) and GM-CSF releases. CONCLUSION: These data show that in vitro trans-Matrigel migration and Matrigel contact modulate eosinophil membrane receptor expression. Consequently, they suggest that migration through basement membrane mediates changes in cell-surface phenotype observed on activated eosinophils and probably prepares them for interactions with tissue components and cells.  相似文献   
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