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1.
Natural killer T cell(NKT) are a unique T cell lineage expressing T cell receptor(TCR)and natural killer cell(NK) lineage receptors, and can recognize glycolipids presented by CD1d molecules expressed on antigen presenting cell through cell recognition pathway. After activated, NKT cells can release large amounts of cytokines, such as IL-4 and IFN-γ, and play a regulatory role in both innate and adaptive immune response. NKT cells can also act as direct effector cells via cytolysis or granulysin. NKT cells play an important role in infectious diseases, autoimmune disease,and cancer.  相似文献   

2.
CD8^+ natural killer T (NKT) cells from EBV-associated tumour patients are quantitatively and functionally impaired. EBV-induced CD8^+ NKT cells drive syngeneic T cells into a Thl-bias response to suppress EBV-associated malignancies. IL-4-biased CD4^+ NKT cells do not affect either syngeneic T cell cytotoxicity or Th cytokine secretion. Circulating mDC1 cells from patients with EBV-associated malignancies impair the production of IFN-T by CD8^+ NKT cells. In this study, we have established a human-thymus-SCID chimaera model to further investigate the underlying mechanism of EBV-induced CD8^+ NKT cells in suppressing EBV-associated malignancies. In the human-thymus-SCID chimera, EBV-induced CD8^+ NKT cells suppress EBV-associated malignancies in a manner dependent on the Thl-bias response and syngeneic CD3^+ T cells. However, adoptive transfer with CD4^+ NKT cells alone inhibits T cell immunity. Interestingly, CD4^+ NKT cells themselves secrete high levels of IL-2, enhancing the persistence of adoptively transferred CD8^+ NKT cells and T cells, thereby leading to a more pronounced T cell anti-tumour response in chimaeras co-transferred with CD4^+ and CD8^+ NKT cells. Thus, immune reconstitution with EBV-induced CD4^+ and CD8^+ NKT cells synergistically enhances T cell tumour immunity, providing a potential prophylactic and therapeutic treatment for EBV-associated malignancies.  相似文献   

3.
Recent study has suggested that innate immune system might play an important role in pregnancy progression. In this study, to investigate whether NK cells and NKT cells, instead of T cells, are the dominant populations of peripheral blood in early pregnancy, flow cytometry was used to detect the percentage and intracellular cytokine expressions of T cells, NK cells, NKT cdls in peripheral blood of non-pregnant women and early pregnant women. In our result, the percentages of NK calls and NKT calls were significantly increased in pregnancy compared to non-pregnancy. However, the percentage of T cells was not changed. We did not detect the Th2-dominance of total lymphocytes or T cells in peripheral blood of early pregnant women and there were also no significant changes of type 1 and type 2 cytokines in T cells, but IFN-γ production in both NK and NKT cells was decreased in early pregnancy. These results suggest that the innate immune system including NK cells and NKT cells should play a pivotal role in pregnancy progression. Type 1/type 2 shift mechanisms in innate immune system during the human early pregnancy should be paid more attention.  相似文献   

4.
The uterus in early pregnancy is a non-lymphoid organ that is enriched in natural killer (NK) cells. Studies to address the role of these abundant human NK cells at the maternal/fetal interface have focused on their response to the major histocompatibility complex (MHC) molecules on fetal trophoblast cells that they contact. The interaction of maternal NK cell receptors belonging to the killer cell immunoglobulin-like receptor (KIR) family with trophoblast MHC class I molecules in pregnancy can regulate NK cell activation for secretion of pro-angiogenic factors that promote placental development. This review will cover the role of KIR at the maternal/fetal interface and focus on KIR2DL4, a KIR family member that is uniquely poised to play a role in pregnancy due to the restricted expression of its ligand, human leukocyte antigen (HLA)-G, by fetal trophoblast cells early in pregnancy. The pathways by which KIR2DL4-HLA-G interactions induce the cellular senescence of NK cells and the role of the resulting senescence-associated secretory phenotype (SASP) in vascular remodeling will be discussed in the context of reproduction.  相似文献   

5.
The proliferation response of γδT cells to the antigen from heat-treated Mycobacterium tuberculosis H37Ra(M.tb Ag)was used as a good model in γδT cell research.From preliminary research it is found that activatedNK cells positively elevated γδT cells proliferation after simulating PBMCs with M.tb Ag.To investigatedifferent behaviors of NK cells,γδNKT cells,γδT cells and relationships between these cell subsets,activationand proliferation of different cell subsets of PBMCs in response to M.tb Ag were analyzed.We demonstratedthat NK cells,γδNKT cells and γδT cells could be activated after stimulation with M.tb Ag.γδNKT cells and γδTcells proliferated while the number of NK cells decreased after 11 day-simulation with M.tb Ag.Meanwhile,atthe early time of stimulation the cytotoxicity of PBMCs was enhanced.Cellular & Molecular Immunology.2004;1(6):467-470.  相似文献   

6.
Role of Interferon-γ in GVHD and GVL   总被引:4,自引:0,他引:4  
Interferon (IFN)-γ, a potent proinflammatory cytokine produced by multiple types of cells (e.g., activated T, NK and NKT cells), plays important and complex roles in both innate and adaptive immune responses. There may be a correlation between the IFN-γ level and GVHD severity in patients receiving allogeneic hematopoietic cell transplantation. However, such a correlation may just reflect the presence of large numbers of activated T cells, and does not necessarily imply a harmful role of IFN-γ in the pathogenesis of GVHD. There has been increasing experimental evidence that IFN-γ is not required and may even inhibit GVHD. Paradoxically, IFN-γ facilitates graft-versus-leukemic (GVL) effects. Thus, IFN-γ blockade is likely deleterious in patients after allogeneic hematopoietic cell transplantation, and not beneficial as previously suggested.  相似文献   

7.
Mesenchymal stem cells (MSCs) are a population of muhipotent cells that can proliferate and differentiate into marrow and non - marrow cell types, such as adipocytes, chondrocytes, myocytes, and so on. In recent years, many researchers have studied whether MSCs are capable of differentiation into neurons in vivo and ex vivo. The result that MSCs - derived neurons express NSE and NF, but don‘t express GFAP suggests MSCs can differentiate into neurons, some researchers have achieved success in promoting functional recovery in Pakinsons and transactional spinal cord injury rat models by use of MSCs - derived neurons. Therefore, MSCs - derived neurons will play an important role in the therapy for a variety of diseases of the nervous system.  相似文献   

8.
Naturally occurring thymus-arisen CD4^+CD25^+ regulatory T (Treg) cells are considered to play a central role in self-tolerance. Precise signals that promote the development of Treg cells remain elusive, but considerable evidence suggests that costimulatory molecules, cytokines, the nature of the TCR and the niche or the context in which the T cell encounters antigen in the thymus play important roles. Analysis of TCR from Treg cells has demonstrated that a large proportion of this population has a higher avidity to self-antigen in comparison with TCR from CD4^+CD25^+ cells and that peripheral antigen is required for their development, maintenance, or expansion. Treg cells have been shown to undergo expansion in the periphery, likely regulated by the presence of self-antigen. Many studies have shown that the involvement of Treg cells in the tolerance induction is antigen-specific, even with MHC-mismatched, in transplantation/graft versus host disease (GVHD), autoimmunity, cancer, and pregnancy. Theses studies concluded a vital role for self-reactive Treg cells in maintenance of the body integrity. Based on those studies, we hypothesize that self-reactive Treg cells are shared among all healthy individuals and recognize same self-antigens and their TCR encodes for few dominant antigens of each organ which defines the healthy self. These dominant self antigens can be regarded as "universal immune code". Cellular & Molecular Immunology.  相似文献   

9.
Cancer vaccines to date have not broadly achieved a significant impact on the overall survival of patients. The negative effect on the immune system of the tumor itself and conventional anti-tumor treatments such as chemotherapy is, undoubtedly, a key reason for these disappointing results. Myeloid-derived suppressor cells(MDSCs) are considered a central node of the immunosuppressive network associated with tumors. These cells inhibit the effector function of natural killer and CD8+ T cells, expand regulatory T cells and can differentiate into tumor-associated macrophages within the tumor microenvironment. Thus, overcoming the suppressive effects of MDSCs is likely to be critical for cancer immunotherapy to generate effective anti-tumor immune responses. However, the capacity of cancer vaccines and particularly their adjuvants to overcome this inhibitory population has not been well characterized. Very small size proteoliposomes(VSSP) is a nanoparticulated adjuvant specifically designed to be formulated with vaccines used in the treatment of immunocompromised patients. This adjuvant contains immunostimulatory bacterial signals together with GM3ganglioside. VSSP promotes dendritic cell maturation, antigen cross-presentation to CD8+ T cells, Th1 polarization, and enhances CD8+ T cell response in tumorfree mice. Currently, four cancer vaccines using VSSP as the adjuvant are in PhaseⅠand Ⅱ clinical trials. In this review, we summarize our work characterizing the unique ability of VSSP to stimulate antigen-specific CD8+ T cell responses in two immunocompromised scenarios; in tumor-bearing mice and during chemotherapy-induced leukopenia. Particular emphasis has been placed on the interaction of these nanoparticles with MDSCs, as well as comparison with other cancer vaccine adjuvants currently in preclinical or clinical studies.  相似文献   

10.
GATA-3 - not just for Th2 cells anymore   总被引:1,自引:0,他引:1  
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11.
目的 研究2型糖尿病患者巨噬细胞内胆固醇外流的变化及ABCA1、ABCG1和SR-B1的表达情况。方法 选取2型糖尿病患者30例(包括合并冠心病组与单纯糖尿病组各15例)和正常对照组15例。分离外周血单核细胞进行巨噬化培养,应用Real-time PCR与Western blot方法测定细胞ATP结合盒受体A1(ABCA1)、ATP结合盒受体G1(ABCG1)和清道夫受体B1(SR-B1)的mRNA及蛋白表达。以5%自身血清及标准血清为接受体测定巨噬细胞胆固醇流出率。 结果ABCG1在2型糖尿病患者巨噬细胞的mRNA与蛋白表达显著低于对照组,而ABCA1与SR-B1的表达在各组间无差异。2型糖尿病患者巨噬细胞的胆固醇流出率也显著低于对照组(P<0.01);ABCG1的mRNA表达与巨噬细胞胆固醇外流率呈显著正相关(r=0.552,r=0.630,P<0.01)。结论 2型糖尿病患者巨噬细胞的胆固醇外流功能明显降低,与ABCG1表达下调相关。  相似文献   

12.
碱基切除修复(base excision repair,BER)通路是DNA损伤修复的关键通路,通路中的8-羟基鸟嘌呤DNA糖苷酶基因(human 8-oxoguanine glycosylase,hOGG1),人类X线交叉互补修复基因(X-ray repair cross-complementing group 1,XRCC1),MutY homolog(MUTYH)基因的单核苷酸多态性影响BER通路中重要的酶和蛋白质的功能,导致修复障碍,最终引起癌症发生.DNA损伤修复基因单核苷酸多态性和肺癌易感性的研究结果尚存在争议,本文对近年来BER通路基因hOGG1Ser326Cys,XRCC1 Arg194Trp,XRCC1 Arg280His,XRCC1 Arg399Gln,XRCC1-77T>C和MUTYHHis324Gln多态性与肺癌易感性的关系的研究进行汇总,并探讨了多项研究对BER基因多态性与不同肺癌亚型的关系以及与吸烟之间关系.基因多态性与肺癌易感性关系受多因素影响,其相关性尚待进一步探索.  相似文献   

13.
碱基切除修复(base excision repair,BER)通路是DNA损伤修复的关键通路,通路中的8-羟基鸟嘌呤DNA糖苷酶基因(human 8-oxoguanine glycosylase,hOGG1),人类X线交叉互补修复基因(X-ray repair cross-complementing group 1,XRCC1),MutY homolog(MUTYH)基因的单核苷酸多态性影响BER通路中重要的酶和蛋白质的功能,导致修复障碍,最终引起癌症发生.DNA损伤修复基因单核苷酸多态性和肺癌易感性的研究结果尚存在争议,本文对近年来BER通路基因hOGG1Ser326Cys,XRCC1 Arg194Trp,XRCC1 Arg280His,XRCC1 Arg399Gln,XRCC1-77T>C和MUTYHHis324Gln多态性与肺癌易感性的关系的研究进行汇总,并探讨了多项研究对BER基因多态性与不同肺癌亚型的关系以及与吸烟之间关系.基因多态性与肺癌易感性关系受多因素影响,其相关性尚待进一步探索.  相似文献   

14.
目的 对深圳市2008-2009年分离到的H1N1季节性流感病毒神经氨酸酶(NA)抑制剂的耐药性进行监测.方法 根据原始临床样本的采集时间,按周抽取了55株2008-2009年分离到的H1N1季节性流感病毒,对其NA片段进行全长测序,选取WHO推荐的疫苗株和部分国内外分离到的H1N1季节性流感病毒作为参考株,运用Mega3.1软件进行种系发生树的构建、耐药相关位点及糖基化位点的分析.结果 对NA片段的序列分析发现2008年有2株(7.1%)出现了H275Y突变,但是2009年则有25株(92.6%)出现了该突变.提示H275Y达菲耐药突变株成为了2009年深圳市社区传播的优势株.同时还发现了一株Q136K变异株,显示对乐感清出现耐药.分子进化分析结果显示,H275Y变异成为了毒株在系统进化树上分布的主要依据.所有的深圳株NA片段上潜在的糖基化位点序列保守.结论 大量H275Y达菲耐药株的出现提示在今后的工作中应当密切关注流感病毒的耐药进展,进一步加强其耐药机制的研究.
Abstract:
Objective To analyze neuraminidase(NA) inhibitor resistance of seasonal H1N1 influenza A viruses isolated in Shenzhen during 2008 to 2009. Methods The NA gene of these viruses were sequenced. Phylogenetic analysis of the sequences was performed with Mega3. 1 software. Results In 2008, most isolates of the seasonal H1 N1 virus were susceptible to neuraminidase inhibitors, but the H275Y mutation in the neuraminidase gene region associated with high-level oseltamivir resistance had been detected in 92.6% of the strains isolated in 2009. Furthermore, a strain with Q136K was found, which showed the resistance to Zanamivir. Conclusion In the light of emerging resistance, close monitoring and understanding of the nature and dynamics of resistance mutations in influenza virus should be a priority.  相似文献   

15.
目的:探讨心肌标志物及部分生化项目检测对于H1N1甲型流行性感冒患者(简称"甲流")的临床意义.方法:对54例H1N1甲流患者(包括4例重症甲流死亡患者)和50例正常对照者用电发光免疫分析、全自动临床化学分析检测H1N1甲流患者心肌标志物及常规生化项目.结果:与正常对照组相比,甲型H1N1感染者在治疗前血清肌酸激酶(C...  相似文献   

16.
目的 对Musashi1发挥功能的 RRM1结构域进行结晶,得到可用来衍射的蛋白晶体,为之后的结构解析打基础。方法 通过构建Musashi1RRM1的原核表达载体,并在BL21中表达、纯化高纯度的蛋白质,通过筛选结晶体条件得到蛋白晶体。结果 通过系统筛选和优化晶体生长条件得到了蛋白晶体。结论 Musashi1 RRM1的蛋白晶体质量较好,满足蛋白晶体衍射和数据收集的要求。  相似文献   

17.
目的 研究1995-2007年深圳市流行的H1N1流感病毒血凝素(HA)的基因特性.方法 选取在该期间分离培养到的64株H1N1流感病毒,对其进行HA片段核苷酸序列测定并推导出其氨基酸序列,用Simmonic软件和Mega软件对其进行分析.结果 深圳市H1N1流感毒株在进化树上可以划分为A、B、C三个分枝.部分2005-2006年毒株与2001年毒株在同一分枝上.通过同源性分析发现部分WHO所推荐的疫苗株在时间上滞后于深圳株.深圳H1N1株的4个抗原决定簇及受体结合位点均发生了氨基酸的替换.除1995年外其余年份的毒株均在137位上发生了氨基酸的缺失.结论 1995-2007年深圳市H1N1毒株氨基酸的变异主要集中在抗原决定簇及受体结合部位.并且抗原决定簇的变异活跃区域随时间的推移发生了转移.  相似文献   

18.
目的:探讨多房囊性肾细胞癌( mu1ti1ocu1ar cystic rena1 ce11 carcinoma,MCRCC)的临床病理学特征、诊断及鉴别诊断。方法回顾性分析18例MCRCC的临床病理学及免疫表型特征,并复习相关文献。结果18例中男性12例,女性6例,年龄26~68岁(平均55.6岁)。影像学检查均示多囊性占位,边界清楚。眼观:肿瘤切面见大小不等的多房囊腔,内含浆液性或血性液体。镜检:肿瘤囊内壁被覆单层透明细胞、复层上皮或上皮缺如,囊内成分大部分流失,纤维性囊壁或囊腔间隔中见灶状透明细胞,呈Ⅰ级细胞核,其为形态学诊断线索。免疫表型:透明细胞CD10、vimentin、EMA均阳性,Ki-67增殖指数低。18例患者平均随访43个月,均无复发或转移,预后良好。结论 MCRCC是一种罕见的肾细胞癌组织学亚型,预后良好,需与肾透明细胞癌囊性变及良性肾囊性病变相鉴别。  相似文献   

19.
Japanese MS patients and controls were examined for the distribution of HLA-DRB1, -DQA1, -DQB1, -DPA1 and -DPB1 alleles using in vitro amplification of genomic DNA and probing with sequence-specific oligonucleotides. No significant difference in frequency of the examined alleles was observed among the two groups. This is in contrast to Norwegian MS patients, where an association to a combination of certain DQA1 and DQB1 alleles has previously been demonstrated.  相似文献   

20.
目的 研究动物源性和人源性甲型H1N1流感病毒(influenza A virus)血凝素(hemagglutinin,HA)的特征,以探讨动物源性和人源性甲型H1N1流感病毒血凝素之间的关系.方法 从美国生物信息中心(NCBI)下载禽(鸟)源、猪源、人源的甲型H1N1流感病毒血凝素氨基酸序列,使用Clustal W2.0生物学软件比较上述血凝素氨基酸序列,并建立甲型H1N1流感病毒血凝素氨基酸序列的进化树.结果 2009年分离的人源性甲型流感病毒血凝素氨基酸序列同源性非常高,达到了99%~100%,而2009年分离的人源性甲型流感病毒血凝素氨基酸序列和禽(鸟)源,猪源的甲型流感病毒血凝素氨基酸序列之间的同源性非常低,只有77%~90%(只有猪源ABW36355和2009年分离的人源甲型流感病毒血凝素氨基酸序列同源性为90%,余同源性为77%~83%);蛋白生物进化树表明禽源(鸟)、猪源、人源的甲型流感病毒血凝素氨基酸序列明显分为3个大的分支.2009年分离的人源性甲型流感病毒血凝素氨基酸序列(ADA71154除外)与疫情前分离得到的人源的血凝素氨基酸序列同源性很低(79%~80%),并且进化树分为3个分支.结论 2009年流行的甲型H1N1流感病毒是一种新的流感病毒,病毒的血凝素氨基酸序列之间的同源性非常高,而和猪、禽(鸟)源的甲型H1N1流感病毒的血凝素氨基酸序列之间的同源性非常低,从这一层面上来讲,目前流行的甲型流感病毒的血凝素的基因并不是猪源和禽源,和疫情前人源的血凝素比对的结果也表明,2009年流行的甲型H1N1流感病毒也并不是直接源于2009年以前的人源流感H1N1病毒,而应该是另有来源.  相似文献   

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