启动子甲基化调控NK-92MI细胞KIR3DL1基因表达

目的:观察NK细胞系NK-92MI细胞中KIR3DL1基因启动子区的甲基化模式及去甲基化和组蛋白乙酰化对基因表达的影响,探讨KIR3DL1基因的表达调控机制.方法:采用亚硫酸氢盐测序法检测NK-92MI细胞中KIR3DL1基因启动子区的甲基化状况,应用甲基化抑制剂5-氮胞苷和(或)组蛋白去乙酰化转移酶抑制剂曲古抑菌素A处理NK-92MI细胞以诱导CpG岛去甲基化和组蛋白乙酰化,观察启动子区CpG岛甲基化和组蛋白乙酰化与KIR3DL1基因表达的关系.结果:NK-92MI细胞中KIR3DL1基因启动子区高甲基化,CpG二核苷酸甲基化频率在70%～100%之间;应用终浓度为2.5 μmol/L和5 μmol/L的5-氮胞苷作用72 h可以诱导NK-92MI细胞中KIR3DL1 mRNA表达量分别增加66.6%和114.6%;单用终浓度为50 nmol/L的曲古抑菌素A不能诱导NK-92MI细胞中KIR3DL1 mRNA表达量增加;此外,曲古抑菌素A和5-氮胞苷联用与单用5-氮胞苷相比也没有协同作用.结论:NK-92MI细胞中KIR3DL1基因表达受启动子甲基化调控.     

杀伤细胞KIR与造血干细胞移植

NK细胞的杀伤细胞免疫球蛋白样受体(killercellimmunoglobulin-likereceptor,KIR)是属于免疫球蛋白样超家族的一系列分子,表达于自然杀伤(naturekiller,NK)细胞和部分T细胞的表面,能识别HLAI类分子。它们可通过与靶细胞表面的HLAI类分子结合,传导激活或抑制信号,从而调节NK细胞和T细胞的活性。造血干细胞移植(hematopoieticstemcelltransplantation,HSCT)过程中,当供者KIR与受者HLAI类分子不匹配时,供者NK细胞功能不被抑制,从而对受者抗原提呈细胞(antigen-presentingcell,APC)和残留肿瘤细胞产生较强的异源反应。研究也已证实供者NK细胞的异源反应活性可提高移植物植入率、促进移植物抗白血病细胞(graft-versus-leukemia,GvL)作用并降低移植物抗宿主病(graft-versus-hostdisease,GvHD)。     

人类杀伤细胞免疫球蛋白样受体基因PCR-SSP分型方法的建立及其应用

目的建立PCR-SSP方法检测人类杀伤细胞免疫球蛋白样受体（KIR）基因。方法参照K／R基因数据库，采用计算机软件设计一系列特异性引物建立PCR-SSP方法，以人类生长激素基因特异性引物作为内对照，以Dynal公司的KIR PCR-SSP分型试剂盒作为验证。结果本实验所设计的KIR特异性引物可检测出所有K／R基因，扩增产物条带清晰，特异性强。结论本实验建立的KIR PCR-SSP方法结果准确，具有可行性。     

尿毒症患者NK1细胞表面受体KIR基因的表达

目的 调查人类自然杀伤(NK)细胞表面免疫球蛋白样受体KIR在尿毒症患者的表达.方法 采用PCR-SSP完成55例尿毒症患者KIR基因分析.结果 尿毒症患者表达16个KIR基因,2DL4、3DL2、3DL3、3DPI基因频率1.00,2DL1、2DL3、3DL1、2DS4基因频率0.73～0.87,2DL2、2DS1、2DS2、2DS3、2DS5基因频率0.11～025,2DL5、3DS1、2DP1基因频率0.30～0.41.对尿毒症患者与部分亚洲地区人群的分布频率比较分析中发现,KIR-2DL4、3DL1、3DL2,3DL3、2DS4(GF 0.73～1.00)和KIR-2DL2、2DL5、2DS1、2DS3、2DS5、3DS1(GF0.11～0.34)与韩国人、日本人、南亚人之间相差＜0.20;KIR-2DL1、2DL3、2DS2与韩国人、日本人、南亚人群之间相差≥0.20,2DL1低于日本人,2DS2低于南亚人,2DL3高于南亚人.结论 55例尿毒症患者普遍带有结构基因2DL4、3DL2、3DL3、3DP1,其次为2DL1、2DL3、3DL1、2DS4,较罕见为2DL2、2DS1、2DS2、2DS3和2DS5;显示尿毒症患者中14个KIR功能基因频率与亚洲其他人群KIR基因频率接近,但是KIR基因多态性与上述不同种族之间存在分布差异.     

杀伤细胞免疫球蛋白样受体(KIR)基因多态性与系统性红斑狼疮的关联性研究

目的 探讨杀伤细胞免疫球蛋白样受体（KIR）基因多态性与系统性红斑狼疮（SLE）的关联性。方法 采用序列特异性引物聚合酶链反应（SSP-PCR）法，分析93例SLE患者和123例无血缘关系的健康对照K／R基因位点的多态性。结果 SLE病例组KIR2DS1（P〈0．001）、KIR2DL2（P〈0．001）基因的阳性率较随机对照组显著升高。具有2个或2个以上活化性基因个体在SLE组（80．7％）较对照组（66．7％）明显增多，差异具有统计学意义（P=0．025）。SLE患者狼疮肾炎与非狼疮肾炎组K／R基因分布频率比较差异无统计学意义。按发病年龄分组后，SLE患者中不同发病年龄组间K／R基因频率分布比较差异无统计学意义。结论 KIR2DS1、KIR2DL2基因频率升高可能与SLE发病相关。     

KIR3 DL1启动子区域 CpG 岛甲基化对抗原表达的影响

目的：探索KIR3DL1启动子区域CpG岛甲基化对抗原表达的影响。方法选择抗原高表达KIR3DL1倡01502和低表达KIR3DL1倡005样本,分别测定启动子区域碱基序列和启动子区CpG岛甲基化程度。对携带有KIR3DL1倡01502、KIR3DL1倡005的NK细胞分别采用5-aza进行去甲基化处理,利用流式细胞仪检测KIR3DL1抗原。结果 KIR3DL1倡01502和KIR3DL1倡005启动子区域－65和－269位存在碱基差异,这导致它们的启动子区域有两个不同的CpG岛。 KIR3DL1倡01502启动子区CpG岛高度甲基化,去甲基化后相应的细胞表面抗原表达显著增加。而携带KIR3DL1倡005的细胞去甲基化处理后,抗原表达没有明显变化。结论 KIR3DL1倡01502启动子区域CpG岛甲基化影响抗原的表达,但是不同抗原表达模式的KIR3DL1等位基因可能存在不同的调控机制。     

KIR基因的进化、表达与功能

KIR基因位于人染色体19q34,呈共显性表达.编码蛋白主要分布于NK细胞和T细胞,特异性识别HLA分子,传导活化或抑制信号,调控杀伤功能.观察表明,骨髓移植时供者KIR表型与受者HLA表型可影响骨髓移植的预后.不同种族的KIR表达有着明显的差异,因此有必要研究中国人的KIR遗传背景.本文对杀伤免疫球蛋白样受体(KIR)的进化、遗传、表达规律和功能进行综述.     

吉林省汉族154例正常人HLA-Cw及KIR基因型频率的分析

目的:了解中国人HLA-Cw与KIR的识别方式,为今后研究其在疾病中的作用提供理论基础.方法:对154例吉林汉族无偿献血者,以PCR-SSP技术进行KIR和HLA-Cw基因分型.根据HLA-Cw与KIR识别方式,分析个体HLA-Cw与相应激活性或抑制性KIR受体的识别情况.结果:吉林汉族人群中,HLA-C2Lys80+ 2DL1的组合频率最高为27.27％,其次分别HLA-C1Asn80+2DL2/2DL3为68.83％,2DS2+HLA-C1Asn80为9.74％,2DS1+HLA-C2Lys80为9.74％,分别有72.08％和21.43％盼观察对象表达KIR2DL1、KIR2DS1而无相应HLA-Cw表达;21.43％的个体表达KIR2DS1而不表达HLA-Cwlys-KIR2DL1配对.2.60％的个体表达KIR2DS2而不表达HLA-Cwasn-KIR2DL2/L3配对.结论:在吉林汉族人群中,抑制性HLA-Cw-KIR受配体对表达高于活化性受配体对,约20％的个体单独表达激活性HLA-Cw-KIR受配体对.     

Graves病患者杀伤细胞免疫球蛋白样受体基因型分析

目的: 探讨杀伤细胞免疫球蛋白样受体(KIR)基因型在Graves病(GD)患者中的分布规律.方法: 采用序列特异性引物聚合酶链反应(PCR-SSP) 的方法,分析96例Graves病患者和96 例正常对照人群的KIR基因型.结果: GD患者中2DS2-,2DL2-,2DL3+,2DL1+,3DL1+,3DS1-,2DL5-,2DS3-,2DS5-,2DS1-,2DS4-基因型频率高于对照组(6.25% vs 0,P<0.05);对照组中,基因频率最高的基因型为2DS2-,2DL2-,2DL3+,2DL1+,3DL1+,3DS1-,2DL5-,2DS3-,2DS5-,2DS1-,2DS4+,该基因型的基因型频率较GD患者组高,且有显著性差异(28.13% vs 10.42%,P<0.01);GD患者组不携带活化性KIR基因的基因型频率较对照组明显升高(10.42% vs 0%,P=0.001).结论: KIR基因型在GD患者与正常人群分布的差异可能与GD的发病有关.     

KIR2DL5基因研究进展

杀伤细胞免疫球蛋白样受体(killer-cell immunoglobulin-1ike receptors，KIRs)是由一组位于19q13.4的紧密成簇的基因编码的免疫球蛋白超家族受体，蛋白结构具有多样性。KIR2DL5由于其独特的基因转录表达特征、单倍体分布、群体分布和表达的多样性，以及D0-D2免疫球蛋白样胞外段结构域和较长的胞内段结构特征而有别于其他KIR，在KIR研究中尤为重要。本文拟对这一基因的研究进展作一综述。     

地塞米松诱导NK-92MI细胞株凋亡机制的研究

目的:探讨地塞米松(DEX)对NK-92MI细胞株杀伤活性及凋亡的影响及机制.方法:用不同浓度的DEX处理NK-92MI细胞:采用MTT比色法测定NK-92MI细胞的增殖率和对靶细胞的杀伤作用;流式细胞术检测NK-92MI细胞凋亡率;RT-PCR 检测凋亡相关基因Bcl-2、Bax的表达.结果:浓度为1×10-8mol/L至1×10-3mol/L的DEX作用NK-92MI细胞24、48、72小时后,对其增殖均有明显抑制作用(P<0.05);效靶比为5∶1时,1×10-8mol/L至1×10-3mol/L的DEX对NK-92MI细胞杀伤活性均有抑制作用,与对照组相比有显著性差异(P＜0.05);DEX可诱导NK-92MI细胞发生凋亡且凋亡诱导作用呈浓度时间依赖性;与对照组相比,DEX组Bcl-2基因表达降低(P＜0.05),Bax基因表达增高(P＜0.01).结论:DEX可以抑制NK-92MI细胞增殖并且降低其杀伤活性,机制可能是通过诱导NK-92MI细胞凋亡,而后者与Bax/Bcl-2基因表达增高有关.     

Killer immunoglobulin-like receptor expression on single cells: a cautionary note

Natural killer (NK) cells keep the surface expression of major histocompatibility complex (MHC) class I molecules under surveillance using killer immunoglobulin-like receptors (KIR). Virus-infected or aberrant cells are frequently characterized by a reduced surface expression of MHC class I antigens and may therefore be removed by cytolysis. NK cells are heterogeneous with regard to the expression of KIR genes. The resulting subpopulations show distinguishable specificities allowing the recognition of cells lacking varying combinations of MHC class I antigens. The KIR expression pattern in single NK cells has previously been analyzed by Husain and colleagues by cDNA preamplification of CD3- CD56+ single cells and subsequent gene-specific polymerase chain reaction. We show here that the data of this study contain inconsistencies. These inconsistencies are discussed in the context of KIR mRNA abundance and single-cell cDNA amplification efficiency.     

桥本甲状腺炎患者杀伤细胞免疫球蛋白样受体基因多态性分析

目的 探讨杀伤细胞免疫球蛋白样受体(killer cell immunoglobulin-like receptor, KIR)基因多态性与桥本甲状腺炎(HT)的关联性.方法 选择100例散发HT患者,260例无血缘关系的正常人作为对照,提取全血基因组DNA,采用序列特异性引物聚合酶链反应(PCR-SSP)的方法,对KIR2DL1～5、KIR3DL1～3、KIR2DS1～5、KIR3DS1及KIR2DP1共15个KIR基因进行检测,其中除KIR2DS5基因外,每个基因均采用2对不同的特异性引物.结果 HT病例组中KIR2DL5基因的基因频率较对照组显著降低(0.200 vs 0.312,RR=0.64,P<0.01).结论 KIR2DL5基因频率的降低可能与HT的发病相关.     

CXCR4基因表达增强K562细胞的趋化作用

目的 构建高表达人CXCR4蛋白的白血病细胞系并测定CXCR4基因对其侵袭转移能力的影响.方法 从外周血淋巴细胞中提取基因组RNA,用RT-PCR扩展编码CXCR4基因片段,将CXCR4基因定向克隆到含有双启动子的真核表达载体PBudCFA.1,采用酶切和序列测定方法鉴定.将所构建的重组质粒用脂质体2000转染K562细胞,Zeoein筛选阳性克隆.流式细胞术和RT-PCR对阳性克隆进行鉴定;用Transwell板检测转染与未转染CXCR4的K562细胞对趋化因子SDF-1趋化活性.结果 成功构建编码CXCR4基因的真核表达质粒PBudCE4.1/CXCR4.经转染入K562细胞,筛选获得能稳定高表达人CXCR4蛋白的K562/CXCR4细胞;K562/CXCR4细胞对SDF-1的趋化能力较K562细胞明显增强.结论 成功构建了转染人CXCR4基因的白血病细胞系,为进一步研究白血病细胞髓外浸润的分子机制奠定基础.     

Pharmacologically upregulated carcinoembryonic antigen-expression enhances the cytolytic activity of genetically-modified chimeric antigen receptor NK-92MI against colorectal cancer cells

Background

The natural killer cell line, NK-92MI, is cytotoxic against various types of cancer. The aim of this study was to develop chimeric antigen receptor-modified (CAR) NK-92MI cells targeting carcinoembryonic antigen-expressing (CEA) tumours and increase killing efficacy by pharmacologically modifying CEA-expression.

Result

We generated anti-CEA-CAR NK-92MI cells by retroviral vector transduction. This genetically-modified cell line recognised and lysed high CEA-expressing tumour cell lines (LS174T) at 47.54?±?12.60% and moderate CEA-expressing tumour cell lines (WiDr) at 31.14?±?16.92% at a 5:1 effector: target (E/T) ratio. The cell line did not lyse low CEA-expressing tumour cells (HCT116) as they did their parental cells (NK-92MI cells). The histone deacetylase-inhibitor (HDAC) sodium butyrate (NaB) and the methylation-inhibitor 5-azacytidine (5-AZA), as epigenetic modifiers, induced CEA-expression in HCT116 and WiDr cells. Although the IC₅₀ of 5 fluorouracil (5-FU) increased, both cell lines showed collateral sensitivity to anti-CEA-CAR NK-92MI cells. The cytolytic function of anti-CEA-CAR NK-92MI cells was increased from 22.99?±?2.04% of lysis background to 69.20?±?11.92% after NaB treatment, and 69.70?±?9.93% after 5-AZA treatment, at a 10:1 E/T ratio in HCT116 cells. The WiDr cells showed similar trend, from 22.99?±?4.01% of lysis background to 70.69?±?10.19% after NaB treatment, and 59.44?±?10.92% after 5-AZA treatment, at a 10:1 E/T ratio.

Conclusions

This data indicates that the effector-ability of anti-CEA-CAR NK-92MI increased in a CEA-dependent manner. The combination of epigenetic-modifiers like HDAC-inhibitors, methylation-inhibitors, and adoptive-transfer of ex vivo-expanded allogeneic-NK cells may be clinically applicable to patients with in 5-FU resistant condition.

     

Vanadium pentoxide increased PTEN and decreased SHP1 expression in NK-92MI cells,affecting PI3K-AKT-mTOR and Ras-MAPK pathways

Vanadium is an air pollutant that imparts immunosuppressive effects on NK cell immune responses, in part, by dysregulating interleukin (IL)-2/IL-2R-mediated JAK signaling pathways and inducing apoptosis. The aim of the present study was to evaluate effects of vanadium pentoxide (V₂O₅) on other IL-2 receptor-mediated signaling pathways, i.e. PI3K-AKT-mTOR and Ras-MAPK. Here, IL-2-independent NK-92MI cells were exposed to different V₂O₅ doses for 24?h periods. Expression of PI3K, Akt, mTOR, ERK1/2, MEK1, PTEN, SHP1, BAD and phosphorylated forms, as well as caspases-3, -8, -9, BAX and BAK in/on the cells were then determined by flow cytometry. The results show that V₂O₅ was cytotoxic to NK cells in a dose-related manner. Exposure increased BAD and pBAD expression and decreased that of BAK and BAX, but cell death was not related to caspase activation. At 400?µM V₂O₅, expression of PI3K-p85 regulatory subunit increased 20% and pPI3K 50%, while that of the non-pPI3K 110α catalytic subunit decreased by 20%. At 200?μM, V₂O₅ showed significant decrease in non-pAkt expression (p?2O₅. No differences were found with non-phosphorylated ERK-1/2. PTEN expression increased significantly at 100?μM V₂O₅ exposure whereas pPTEN decreased by 18% at 25?μM V₂O₅ concentrations, but remained unchanged thereafter. Lastly, V₂O₅ at all doses decreased SHP1 expression and increased expression of its phosphorylated form. These results indicated a toxic effect of V₂O₅ on NK cells that was due in part to dysregulation of signaling pathways mediated by IL-2 via increased PTEN and decreased SHP1 expression. These results can help to explain some of the known deleterious effects of this particular form of vanadium on innate immune responses_.     

Killer cell immunoglobulin-like receptor gene diversity in a Caucasian population of Southern Brazil

Killer immunoglobulin-like receptors (KIR) regulate the activity of natural killer and T cells through an interaction with specific human leucocyte antigen (HLA) class I molecules on target cells. Diversity in KIR gene content, KIR allelic and haplotype polymorphism has been observed between different ethnic groups. However, most population studies on KIR variability have focused on Europe and Asia, while Americas, Oceania and Africa remain poorly studied. The aim of this study was to analyse the variability of KIR genes in 200 healthy nonrelated individuals from the Southern Brazilian population. KIR genes and HLA-A, -B and -Cw were genotyped using polymerase chain reaction-sequence-specific primers. Southern Brazilian population demonstrated several similarities to states that are closer geographically and distinct differences with Northern Brazil in the frequency of genes KIR2DS1, 2DS2, 2DS3, 2DS5, 3DL1, 3DS1, 2DL1 and 2DL2. The activating gene KIR2DS5 was the least frequent locus found in our group. Interaction of KIR/HLA was more common in the 2DS1−/2DL1+/C2+ association. This study demonstrated the diversity of KIR genes and of KIR/HLA association in a Caucasian group of Southern Brazil, establishing differences and similarities to other different populations.     

Killer cell immunoglobulin-like receptor genotypes in the Turkish population

One hundred eighty-seven healthy and unrelated volunteers from various regions of Turkey were selected for the study. Killer-cell immunoglobulin-like receptors (KIR) genotyping was performed by polymerase chain reaction using commercial sequence-specific oligonucleotide probe (SSOP) kits. Gene frequencies of the Turkish population were determined by direct counting of the positive and negative loci. The genotype data is publicly available in the Allele Frequencies Net Database under the population name “Turkey KIR pop 3” number “3399”.     

Killer immunoglobulin-like receptor and human leukocyte antigen expression as immunodiagnostic parameters for pelvic endometriosis

PROBLEM: We investigated host immunologic responses to endometriosis by comparing immune cell surface antigens in peripheral blood (PB) and peritoneal fluid (PF) from women with endometriosis with those in PB and PF from other patients. METHOD OF STUDY: Japanese women with endometriosis (n = 56) were compared with controls with other laparoscopic diagnoses (n = 68). PB and PF were collected at the time of laparoscopy for flow cytometry. RESULTS: No significant difference in phenotypic parameters of T cells (CD3, CD4, and CD8), B cells (CD19), natural killer (NK) cells (CD56), or monocytes/macrophages (CD14) was seen between women with and without endometriosis. However, increased killer immunoglobulin-like receptor (CD158a) expression by NK cells and decreased human leukocyte antigen (HLA)-ABC and -DR expression by macrophages, all suggesting decreased functional activation were found in endometriosis. These markers showed significant association with endometriosis by odds ratio, logistic regression, and decision tree analyses. CONCLUSIONS: Increased CD158a(+) NK cells in PB and PF indicated decreased NK cell cytotoxicity in endometriosis, while decreased HLA expression on PF macrophages suggested impaired antigen presentation. Thus, aberrant immune responses by NK cells and macrophages may represent risk factors for endometriosis.