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101.
Cervical cancer is strongly associated with infection of oncogenic types of human papillomavirus (HPV). However, HPV infection alone is not sufficient for progression to cervical cancer. It is now recognized that host immunogenetic background participates in the control of HPV infection and development of cervical cancer. Interleukin-18 (IL-18) is a multifunctional cytokine that induces interferon-gamma secretion and plays a central role in antitumor immunity. The aim of this study is to determine if potentially functional polymorphisms in IL-18 gene are associated with risk of HPV-induced cervical cancer in Taiwanese women. Pre-Developed TaqMan Allelic Discrimination Assay was used to genotype IL-181297 T/C, −607 C/A, −380 C/G, −137 G/C, and +105 A/C polymorphisms in a hospital-based study of 470 women with cervical squamous cell carcinoma (CSCC) and 722 age-matched healthy control women. The presence and genotypes of HPV in CSCC was determined by PCR. None of the polymorphisms or any haplotype was found to have significant differences in distribution among all subjects with CSCC, those with HPV-16 positive CSCC, and controls. Our results suggest that the IL-181297 T/C, −607 C/A, −380 C/G, −137 G/C, and +105 A/C polymorphisms are not associated with susceptibility to CSCC in Taiwanese women.  相似文献   
102.
目的 探讨灵芝多糖(GLP)对外周血淋巴细胞免疫分群的影响及其作用机制.方法 取肿瘤患者和正常人的外周血,分离外周血单个核细胞(PBMC)后,用不同剂量的GLP(10 ng/ml、50ng/ml和100 ng/ml)刺激后,用流式细胞仪检测DC细胞表面分子(HLA-DR、CD83和CD11c)、Th1细胞、Th2细胞和NK(CD3-CD56+)细胞数;并进一步用免疫磁珠分选出正常人外周血CD4+ Th细胞后用不同浓度GLP刺激24h后,荧光实时定量Q-PCR检测Th1和Th2细胞因子的表达水平,Westernblot分析Th1分化相关的转录因子水平.结果 灵芝多糖可以在体外呈浓度依赖性增加外周血中Th1细胞亚群和DC共刺激分子的表达(P<0.01),并且增加STAT4的表达和IL-12、IFN-γ和TNF-α的mRNA的表达水平(P<0.01).结论 灵芝多糖可能通过增加Th细胞STAT4的表达水平,促进其向Th1细胞分化,并增加Th1的分泌细胞因子.  相似文献   
103.
目的对比分析轻症和重症甲型H1 N1流感患者的细胞免疫学特征,为该病的病情监测和治疗提供科学依据。方法收集2009年7月1日至2009年12月31日于宁波市第二医院及宁海县第一医院就诊并确诊为甲型H1N1流感的204名患者作为病例组,其中轻症组52例,重症组152例,选取同时期的26名健康志愿者作为对照组;采用流式细胞仪检测各组外周血淋巴细胞亚群,采用ELISA方法检测各组血清干扰素-γ(IFN-γ)及白细胞介素-4(IL-4)水平。结果 H1N1流感患者重症组外周血淋巴细胞计数降低显著,与健康对照组及轻症组患者比较差异均有统计学意义(P<0.01);重症组T淋巴细胞、NK细胞、CD4+T及CD8+T淋巴细胞计数、百分比均较轻症组显著降低( P<0.01),B淋巴细胞及CD4+T/CD8+T比值虽然较轻症组降低,但差异无统计学意义(P=0.11,0.175);轻症组和重症组血清IFN-γ水平均较健康对照组降低,但是重症组降低更为显著(与健康对照组和轻症组比较,P<0.01);同样,轻症组和重症组血清IL-4水平均较健康对照组降低,但各组间比较统计学差异均无显著性意义(P>0.05)。结论甲型H1N1流感患者免疫功能的异常与病情轻重有一定关系,尤其是细胞免疫功能,监测患者的免疫功能变化,对于判断患者的病情有较好的参考价值。  相似文献   
104.
Protein-bound polysaccharide-K (PSK) is a hot water extract from Trametes versicolor mushroom. It has been used traditionally in Asian countries for its immune stimulating and anti-cancer effects. We have recently found that PSK can activate Toll-like receptor 2 (TLR2). TLR2 is highly expressed on dendritic cells (DC), so the current study was undertaken to evaluate the effect of PSK on DC activation and the potential of using PSK as a vaccine adjuvant. In vitro experiments using mouse bone marrow-derived DC (BMDC) demonstrated that PSK induces DC maturation as shown by dose-dependent increase in the expression of CD80, CD86, MHCII, and CD40. PSK also induces the production of multiple inflammatory cytokines by DC, including IL-12, TNF-α, and IL-6, at both mRNA and protein levels. In vivo experiments using PSK as an adjuvant to OVAp323–339 vaccine showed that PSK as adjuvant leads to enlarged draining lymph nodes with higher number of activated DC. PSK also stimulates proliferation of OVA-specific T cells, and induces T cells that produce multiple cytokines, IFN-γ, IL-2, and TNF-α. Altogether, these results demonstrate the ability of PSK to activate DC in vitro and in vivo and the potential of using PSK as a novel vaccine adjuvant.  相似文献   
105.
《Autoimmunity》2013,46(3):157-165
We investigated the effect of oral administration of type I interferon (IFN) in experimental allergic neuritis (EAN) in Lewis rats immunized with bovine peripheral nerve myelin. Starting at 7 days preceding immunization, rats were fed daily until sacrifice either with 5000 U rat IFN-α/β or mock-IFN. The clinical severity of EAN was significantly reduced in IFN-α/β fed animals compared to mock-IFN fed controls. Demyelination, but not inflammation, was decreased in IFN-α/β fed compared to mock-IFN fed rats at day 20 after immunization. In situ IFN-γ production and inflammation were reduced when evaluated by immunocytochemistry at day 13 after immunization. Spleen cells from IFN-α/β fed compared to mock-IFN fed EAN rats showed significantly reduced proliferation to stimulation with Con A or peripheral nerve myelin. IFN-γ production in draining lymph node cells was significantly reduced after stimulation with bovine peripheral nerve myelin. Our data suggest that oral administration of IFN-α/β reduces the severity of EAN, possibly by a reduction in production.  相似文献   
106.
Curcumin (diferuloylmethane), found in the spice turmeric, exhibits anti-inflammatory, antioxidant, and chemopreventive activities. However, the effect of curcumin on the immunological responses largely remains unknown. In this study we have investigated the effect of curcumin on mitogen (phytohaemagglutinin; PHA) stimulated T-cell proliferation, natural killer (NK) cell cytotoxicity, production of cytokines by human peripheral blood mononuclear cells (PBMCs), nitric oxide (NO) production in mouse macrophage cells, RAW-264.7. Furthermore, we have carried out an electromobility shift assay to elucidate the mechanism of action of curcumin at DNA protein interaction level. We observed that curcumin inhibits PHA-induced T-cell proliferation, interleukin-2 production, NO generation, and lipopolysachharide-induced nuclear factor-κB (NF-κB) and augments NK cell cytotoxicity. Our results suggest that curcumin most likely inhibits cell proliferation and cytokine production by inhibiting NF-κB target genes involved in the induction of these immune parameters.  相似文献   
107.
108.
109.
Tumor necrosis factor alpha (TNFα) in intestinal mucosa plays a key role in the inflammation characterizing Crohn’s disease (CD). Moreover, adhesion molecule syndecan-1 mediates the maintenance of mucosal integrity and supports tissue repair. Therefore, our aim in this study was to correlate simultaneous expression of TNFα and syndecan-1 in patients affected by CD. Biopsies from 10 patients with CD of large bowel and 10 subjects with irritable bowel syndrome (controls) were studied by immunohistochemical detection of both TNFα and syndecan-1 on successive serial sections. Overall labeling index (OLI) was indicated by the percentage of positive stromal (i.e., nonepithelial) cells/1000 counted in randomized fields, whereas selected labeling index (SLI) was represented by the simultaneous evaluation of both molecules in a same single selected field of each specimen. TNFα and syndecan-1 OLI were significantly higher in CD compared with controls, while SLI showed an inverse relationship between the molecules in CD which was not observed in controls. Epithelial syndecan-1 cytoplasmatic staining of superficial epithelium was associated with loss of basolateral staining in the crypts and high stromal TNFα in CD. In conclusion, TNFα and syndecan-1 expression is increased in the intestinal mucosa of patients with CD. However, the expression of the two molecules is inversely related when a single field is considered, these data supporting the possibility of a downregulation exerted by TNFα.  相似文献   
110.
Abstract

Objective: The aim of the present study was to evaluate the therapeutic potential of autologous DCs loaded with whole tumor cell lysate of CTVT generated under a simplified and rapid procedure in vitro production process, in a vulvar submucosal model of CTVT in dogs.

Materials and methods: We generated a model of intravulvar CTVT in dogs. A CTVT lysate antigen was prepared according to the method of 1-butanol and after administered with complete Freund's adjuvant via subcutaneous in female healthy dogs and challenge with CTVT cells to corroborate the immunogenicity. Short-time generated dendritic cell pulsed with CTVT whole-lysate was performed, and analyzed by FITC-dextran uptake assay and characterized using anti-canine monoclonal antibodies CD14, CD80, CD83, and DLAII by flow cytometry. Dendritic cell therapy was administered in a frequency of three times every 2 weeks when the CTVT had 4 months of growth and 89?±?5 cm diameter. The CD3+, CD4+ and CD8+ lymphocytes were determined by flow cytometry, and IFN-γ by ELISA assay.

Results and discussion: The administration of CTVT whole-lysate resulted in tumor prevention. The short-time generated dendritic cell pulsed with CTVT whole-lysate administration resulted in an efficient reduction and elimination of CTVT, probably due to the increase in lymphocyte populations (CD3+, CD4+, and CD8+), IFN-γ production and tumor infiltrating lymphocytes.

Conclusion: In conclusion, this study demonstrates the efficacy of immunotherapy based in short-time generated dendritic cell pulsed with CTVT whole-lysate for the treatment of CTVT, and offer veterinary oncologists new alternative therapies to treat this and another malignancy.  相似文献   
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