黏病毒抗性蛋白A基因多态性与HBV感染转归的关系

目的 探讨干扰素诱导的黏病毒抗性蛋白A(MxA)基因单核苷酸多态性(SNP)对乙型肝炎病毒(HBV)感染自然转归的影响.方法 收集湖北地区160例HBV自限感染者和243例慢性HBV感染者的外周血标本,应用聚合酶链反应-限制性片段长度多态性分析方法,检测MxA启动子-88,-123位点基因型.结果 MxA启动子-88G/T位点基因型和等位基因在慢性HBV感染者和自限性感染者中的分布差异有高度显著性.HBV自限性感染者MxA启动子-88位点GG基因型和G等位基因频率分别为41.3%和62.8%,均较慢性感染者频率52.7%和74.9%低(P=0.025和P= 0.001),而TT基因型和T等位基因频率分别为15.6%和37.2%,均较慢性感染者频率2.9%和25.1%高(P=0.000和P= 0.001),比值比为6.24,95%可信限2.63～14.81.然而,MxA启动子-123位点不同基因型和等位基因在HBV自限性感染组和慢性感染组间的分布频率差异均无统计学意义(P＞0.05).结论 MxA启动子-88G/T位点多态性与HBV感染后的结局有关,其中TT基因型或T等位基因的存在可能有利于HBV感染后的清除.     

MxA启动子和elF-2a调节区2基因多态性对HBV感染自然转归的影响

目的探讨干扰素诱导的黏病毒抗性蛋白A(MxA)和真核细胞起始因子2a调节区2(elF-2a-reg2)基因的单核苷酸多态性(SNP)对乙型肝炎病毒(HBV)感染自然转归的影响。方法收集湖北地区160例HBV自限感染者和243例慢性HBV感染者的外周血标本,应用聚合酶链反应-限制性片段长度多态性分析方法,检测MxA启动子-88、-123位点及elF-2a-reg2基因型。结果 MxA启动子-88G/T位点基因型和等位基因在慢性HBV感染者和自限性感染者中的分布差异有统计学意义(P<0.05)。HBV自限性感染者MxA启动子-88位点GG基因型和G等位基因频率分别为41.3%、62.8%,均较慢性感染者频率52.7%、74.9%低(P=0.025和P=0.001),而TT基因型和T等位基因频率分别为15.6%、37.2%,均较慢性感染者频率2.9%、25.1%高(P=0.000和P=0.001),比值比为6.24,95%可信限2.63～14.81。然而,MxA启动子-123位点、elF-2a-reg2基因的不同基因型和等位基因在HBV自限性感染组和慢性感染组间的分布频率差异均无统计学意义(P>0.05)。结论 MxA启动子-88G/T位点多态性与HBV感染后的结局有关,其中TT基因型或T等位基因的存在可能有利于HBV感染后的清除。     

IFN-γ基因+874位点单核苷酸多态性与乙型肝炎病毒感染关系的研究

【目的】研究干扰素（IFN-γ）基因＋874位点单核苷酸多态性与乙型肝炎病毒（HBV）感染、转归的关系,探讨HBV感染的遗传易感因素。【方法】采用序列特异性引物-聚合酶链反应（PCR—SSP）技术检测231例慢性HBV感染者、165例自限性HBV感染者和135名正常对照者IFN-γ基因第一内含子＋874位点T／A单核苷酸多态性。【结果】慢性HBV感染组IFN-γ基因＋874位点AA基因型频率（78．8％）显著高于正常对照组（64．4％）（x^2=9．60．P=0．008）,而自限性HBV感染组（62．4％）和对照组之间差异无显著性（x^2=0．16,P=0．92）。进一步比较慢性HBV感染者IFN-γ基因＋874住点单核苷酸多态性与HBV—DNA复制的关系,发现IFN-γ基因＋874住点基因型和等住基因频率在低水平HBV-DNA组和高水平HBV-DNA组之间的分布差异无显著性。【结论】IFN-γ基因第一内含子＋874位点多态性与慢性HBV感染有关,提示该位点多态性可能在决定个体HBV感染遗传易感性方面有一定意义。     

IFN-γ+874A/T基因多态性与再生障碍性贫血免疫抑制治疗疗效的关系

目的:探讨IFN-γ+874A/T基因多态性与再生障碍性贫血(AA)易感性以及免疫抑制治疗疗效的关系。方法:收集四川大学华西医院血液科确诊的133例汉族AA患者的静脉血标本,其中有62例患者接受免疫抑制治疗且观察期超过4个月,100例汉族健康成人作为对照组。采用PCR、琼脂糖凝胶电泳和DNA测序法检测AA患者和健康对照者IFN-γ基因+874A/T单核苷酸多态性。结果:1AA组中IFN-γ+874 TT基因型频率和T等位基因的分布频率分别为24.8%和48.9%,显著高于健康对照组的7.0%、23.0%(P0.001,P0.001);2 62例AA患者中34例免疫抑制治疗有效,其中携带IFN-γ+874A/T位点TT基因型和T等位基因者的有效率分别为75%及71.4%,显著高于携带AA基因型和A等位基因者的27.3%和41.2%(P=0.008,P=0.001)。结论:IFN-γ+874A/T基因多态性与AA易感性和免疫抑制治疗疗效可能有关。     

γ干扰素基因多态性与鼻咽癌易感性的分析

目的探讨γ干扰素(IFN-γ)基因多态性位点rs2430561(+874T/A)和rs1861494(+2109A/G)与鼻咽癌(NPC)遗传易感性的关系。方法收集NPC患者150例和健康对照者150名,+874T/A位点采用聚合酶链反应(PCR)-序列特异引物技术(SSP)进行基因分型,+2109A/G位点采用PCR-限制性片段长度多态性方法(RFLP)进行基因分型。结果与AA基因型相比,rs2430561+874T/A位点TT基因型患病风险显著降低[比值比(OR)=0.132,95%可信区间(CI)=0.022～0.800,P=0.028]。rs1861494+2109A/G位点各基因模型比较,差异均无统计学意义(P0.05)。结论 IFN-γrs2430561+874T/A位点基因多态性与NPC遗传易感性相关联。     

广西壮族人群ADIPOQ基因rs2241766T/G多态性与T2DM易感性的相关性分析

摘要:目的探讨脂联素基因(ADIPOQ)rs2241766T/G位点单核苷酸多态性(SNP)与广西壮族人群新发2型糖尿病(T2DM)易感性及不同代谢参数之间的相关性。方法采用 SNPscan高通量技术检测广西地区212例新发T2DM患者和289例健康人对照者的rs2241766T/G基因分型,统计并分析二者的差异性。结果rs2241766T/G 位点存在GG、TG和TT基因型及G和T等位基因;T2DM组与对照组基因型频率差异有统计学意义(X = 6.294,P = 0.043) ;TG( OR= 2.443, 95%CI:1.197-4.988 ,P=0.014)、TT( OR= 2.057 ,95%CI:1.017-4.159, P=0.045)及TG+TT( OR= 2.222, 95%CI:1.122~4.402 ,P=0.022)基因型与T2DM风险增加显著相关;在调整性别和年龄共同混杂因素后,TG .TT和TG+TT基因型患T2DM风险分别是GG基因型的2.863倍 ( OR= 2.863 ,95% CI:1.352~ 6.060,P=0.006)、2.291倍(OR=2.291, 95%Cl:1.094~4.800, P=0.028)和2.532 倍(OR= 2.532,95%CI:1.235~ 5.192 ,P=0.011);与健康人对照组比较,不同基因型T2DM患者的多种临床生化代谢指标间的差异有统计学意义(P均<0.05),且证实rs2241766T/G SNP可影响患者肌酐(Gr)水平(P=0.049)。结论ADIPOQ rs2241766T/G SNP与广西壮族人群T2DM易感性增加相关,或可作为预测T2DM风险的潜在遺传标志物。     

阜阳市慢性乙型肝炎病毒感染者HBV基因型调查

目的了解阜阳市慢性乙型肝炎病毒(HBV)感染者HBV基因型分布状况。方法选择165例HBVDNA阳性的慢性HBV感染者,采用型特异性聚合酶链反应(PCR)检测HBV基因型。结果 165例慢性HBV感染者中HBV基因型B型46例(27.9%)、B/C混合型29例(17.6%)、C型90例(54.5%),未发现其他基因型。结论阜阳市慢性HBV感染者基因型为B、B/C和C型,其中基因C型是主要流行株。     

云南三民族人群eNOS G894T多态性与HBV感染的相关性研究

目的:分析云南省西双版纳基诺族、傣族和僾尼族人群eNOS G894T多态性与HBV感染的相关性。方法:采用整群随机抽样的方法运用PCR-RFLP方法对三民族人群eNOS G894T位点进行基因分型。结果:(1)僾尼族人群HBV感染率显著高于基诺族及傣族(P均为0.000)。(2)僾尼族人群eNOS G894T位点基因型与等位基因分布频率与其他两民族显著不同(P均小于0.005),GG基因型与G等位基因频率降低,而TT基因型与T等位基因频率升高。(3)HBV感染组eNOS G894T位点GG基因型与G等位基因频率显著低于正常对照组,而TT基因型与T等位基因频率显著高于HC组(P均为0.000)。(4)以非条件logistic回归校正混杂因素后,在G隐性模式下,HBV感染组与正常对照组差异有显著性意义(P为0.000;OR为0.311;95%CI为0.179～0.540)。结论:eNOS G894T基因型和等位基因频率具有民族差异,并且其多态性与HBV感染密切相关,基因型为GG纯合子的个体降低了HBV感染风险。     

白介素13基因+1923C/T 及+2044G/A 多态性与支气管哮喘的相关性研究

目的：探讨白细胞介素13(IL-13)基因第3内含子+1923C/T 及第4外显子+2044G/A 多态性与哮喘的关系。方法采用聚合酶链反应限制性片段长度多态性(PCR-RFLP)方法,检测100例哮喘患者和100例健康人群 IL-13基因+1923C/T 及+2044G/A 位点单核苷酸多态性,分析其基因型和等位基因分布频率。结果 IL-13+1923C/T 位点基因型 CC、CT 和 TT 在哮喘组分布频率为21.0%、41.0%和38.0%,对照组为41.0%、44.0%和15.0%。IL-13+2044G/A 位点基因型 GG、GA 和 AA 在哮喘组分布频率为51.0%、39.0%和10.0%,对照组为70.0%、25.0%和5.0%。IL-13+1923C/T 和+2044G/A 位点各基因型分布在两组间差异有统计学意义(χ2=16.54,P <0.01;χ2=7.71,P <0.05)。结论 IL-13基因+1923C/T 和+2044G/A 多态性与哮喘易感性相关,携带+1923T 或+2044A 等位基因的个体患哮喘的风险更大。     

CTLA-4基因启动子区多态性与系统性红斑狼疮的关系分析

目的分析细胞毒性T淋巴细胞相关抗原-4(CTLA-4)基因启动子区-1722和-318位点多态性与系统性红斑狼疮(SLE)的关联性。方法利用聚合酶链反应-限制性片段长度多态性分析方法对112例患者和110例健康者检测-1722位点胸腺嘧啶/胞嘧啶(T/C)和-318位点T/C的多态性,并进行基因扩增,依据各条带相对分子质量的大小对CTLA-4基因-1722位点T/C和-318位点T/C进行分型。结果以组一为例,CTLA-4基因-1722位点TC基因型频率明显升高,差异有统计学意义(32%vs31%,P=0.015,OR=0.618);CC基因型频率明显升高,差异也有统计学意义(30%vs21%,P=0.039,OR=1.586);TT基因型频率虽有降低趋势,但差异无统计学意义(0%vs7%,P=0.346,OR=1.008),SLE组和健康对照组CTLA-4基因-1722位点等位基因C基因型频率明显升高,差异有统计学意义(61%vs68%,P=0.053,OR=1.781);携带者C基因型频率明显降低,差异也有统计学意义(52%vs59%,P=0.040,OR=1.652)。另外列出了CTLA-4基因-1722位点TC、CC和TT基因型的电泳结果及CTLA-4基因-318位点PCR单扩结果。结论 CTLA-4基因启动子区-1722的TC、CC基因可能是SLE易感性的一个危险因子,CTLA-4基因启动子区-1722基因型和CTLA-4基因启动子区-1722和-318位点的活性水平可作为推测SLE易感性的参考指标。     

Ligation of the T cell receptor complex results in activation of the Ras/Raf-1/MEK/MAPK cascade in human T lymphocytes.

Stimulation of T cells with antibodies directed towards the T cell receptor complex results in the activation of mitogen-associated protein kinase (MAPK). Two pathways have been described in other cell types that can lead to MAPK activation. One of these pathways involves the activation of Ras, leading to the activation of Raf-1, and the subsequent activation of MEK (MAPK or ERK kinase). The contribution of this pathway in T cells for anti-CD3 or phorbol myristate acetate (PMA)-mediated MAPK activation was examined. We detected the kinase activities of Raf-1 and MEK towards their substrates (MEK for Raf-1 and MAPK for MEK) in this pathway leading to the activation of MAPK. Stimulation of the T cells with either anti-CD3 antibody or PMA resulted in a rapid activation of both Ras and Raf-1. MEK activity towards kinase-active or -inactive recombinant MAPK also increased upon stimulation. In addition, both MAPK and p90rsk were activated in these cells. We suggest that activation of MAPK and the subsequent activation of ribosomal S6 kinase (p90rsk) occurs by the Ras/Raf-1/MEK cascade in T lymphocytes stimulated by ligation of the T cell receptor complex.     

T1/ST2-deficient mice demonstrate the importance of T1/ST2 in developing primary T helper cell type 2 responses

We have generated mice with a deficiency in T1/ST2 expression to clarify the roles of T1/ST2 in T helper cell type 2 (Th2) responses. Using immunological challenges normally characterized by a Th2-like response, we have compared the responses of T1/ST2-deficient mice with those generated by wild-type mice. Using a primary pulmonary granuloma model, induced with Schistosoma mansoni eggs, we demonstrate that granuloma formation, characterized by eosinophil infiltration, is abrogated in T1/ST2-deficient mice. Furthermore, we clearly demonstrate that in the absence of T1/ST2 expression, the levels of Th2 cytokine production are severely impaired after immunization. Thus, in a secondary pulmonary granuloma model, draining lymph node cells from the T1/ST2-deficient animals produced significantly reduced levels of IL-4 and IL-5, despite developing granulomas of a magnitude similar to those of wild-type mice and comparable antigen-specific immunoglobulin isotype production. These data clearly demonstrate that T1/ST2 expression plays a role in the development of Th2-like cytokine responses and indicate that effector functions are inhibited in its absence.     

Production of a T cell hybridoma that expresses the T cell receptor gamma/delta heterodimer

We have produced a T cell hybridoma line by fusion of an IL-2-dependent, long-term T cell receptor (TCR) gamma/delta+ Thy-1+, bone marrow-derived, dendritic epidermal cell line to the BW5147 tumor line. The resultant hybridoma was rapidly growing, lymphokine independent, and expressed T3 in association with the TCR gamma/delta heterodimer. Several subclones of the hybridoma line produced easily detectable levels of IL-2 after stimulation by anti-T3 or Con A. The availability of these cloned cell lines should greatly facilitate further functional, biochemical, and molecular studies of the TCR delta chain.     

Identification of a T3/T cell receptor complex in chickens

A mouse mAb, CT-3, recognizes on chicken T cells a complex of three polypeptides, Mr 20,000, 19,000, and 17,000, two of which are N-glycosylated. The CT-3 antibody is mitogenic for chicken T cells, and it coprecipitates two additional polypeptides of Mr 49,000 and 38,000 in lysates of T cell membranes. Ontogeny studies revealed that 5-6 d after thymic influx of hemopoietic stem cells, their thymocyte progeny begin to express the T3/TCR complex. After hatching 1 wk later, the CT-3+ cells begin splenic migration in large numbers.     

A large subpopulation of avian T cells express a homologue of the mammalian T gamma/delta receptor

This report describes an avian TCR molecule, TCR1, whose molecular characteristics, signal-transducing property, and tissue distribution suggest that it is a homologue of the mammalian TCR-gamma/delta. TCR1+ cells are the first to be generated in the thymus during ontogeny, preceding other T3+ cells by approximately 3 d. Unlike their mammalian counterpart, TCR1+ cells constitute a relatively large subpopulation of peripheral T cells in mature chickens. These results suggest a phylogenetically important role for this receptor in T cell development and function.     

Human epidermal T cells predominantly belong to the lineage expressing alpha/beta T cell receptor

The epidermis of clinically normal-appearing human skin harbors a phenotypically heterogeneous population of T lymphocytes (TCs), the majority of which are CD2+/CD3+/CD5+ "memory" cells, but in an unactivated state, and express the TCR-alpha/beta. In contrast to murine skin, only a very minor subpopulation of CD3+ cells in the human epidermis bears the TCR-gamma/delta. Epidermal TCs primarily are distributed along the rete ridges in the basal keratinocyte layer and are often in close apposition to Langerhans cells (LCs). These TCs were propagated from epidermal cell suspensions after stimulation with TC activating agents (Con A, rIL-1, rIL-2), then evaluated for phenotypic features and TCR diversity. Similar to the in situ situation, most were CD4-/CD8+/TCR-alpha/beta+. In addition, two cultures contained TCR- gamma/delta+ cells; one of these determined to be an adherent CD4-/CD8+ population. Epidermal TCs were significantly (p less than 0.0001) more abundant in the sole than in the other body regions examined (i.e., 40 vs. 7 CD3+ cells/linear centimeter of epidermis) and seemed to have a particular affinity for the acrosyringial epithelium of eccrine sweat ducts. Moreover, the sole usually contained a greater number of CD8+ relative to CD4+ TCs, whereas the epidermal CD4/CD8 ratio in the trunk and extremities was quite variable, although the trend also was towards a slightly larger percentage of CD8+ cells. Collectively, our data suggest that the volar epidermis has a unique microenvironment which is responsible for both the higher density of TCs, preferentially CD8+, and lower number of LCs. This study has not only provided evidence for significant regional variability in the human epidermal TC population of normal skin, but also strengthens the concept for skin-associated lymphoid tissues (SALT), whereby memory TCs recirculate back to the epidermis and interact with resident antigen-presenting cells (i.e., LC).     

Retroviral transformation in vitro of chicken T cells expressing either alpha/beta or gamma/delta T cell receptors by reticuloendotheliosis virus strain T

Exposure of normal juvenile chicken bone marrow cells to the replication defective avian reticuloendotheliosis virus strain T (REV- T) (chicken syncytial virus [CSV]) in vitro resulted in the generation of transformed cell lines containing T cells. The transformed T cells derived from bone marrow included cells expressing either alpha/beta or gamma/delta T cell receptors (TCRs) in proportions roughly equivalent to the proportions of TCR-alpha/beta and TCR-gamma/delta T cells found in the normal bone marrow in vivo. Essentially all TCR-alpha/beta- expressing transformed bone marrow-derived T cells expressed CD8, whereas few, if any, expressed CD4. In contrast, among TCR-gamma/delta T cells, both CD8+ and CD8- cells were derived, all of which were CD4-. Exposure of ex vivo spleen cells to REV-T(CSV) yielded transformed polyclonal cell lines containing > 99% B cells. However, REV-T(CSV) infection of mitogen-activated spleen cells in vitro resulted in transformed populations containing predominantly T cells. This may be explained at least in part by in vitro activation resulting in dramatically increased levels of T cell REV-T(CSV) receptor expression. In contrast to REV-T(CSV)-transformed lines derived from normal bone marrow, transformed lines derived from activated spleen cells contained substantial numbers of CD4+ cells, all of which expressed TCR- alpha/beta. While transformed T cells derived from bone marrow were stable for extended periods of in vitro culture and were cloned from single cells, transformed T cells from activated spleen were not stable and could not be cloned. We have therefore dissociated the initial transformation of T cells with REV-T(CSV) from the requirements for long-term growth. These results provide the first demonstration of efficient in vitro transformation of chicken T lineage cells by REV- T(CSV). Since productive infection with REV-T(CSV) is not sufficient to promote long-term growth of transformed cells, these results further suggest that immortalization depends not only upon expression of the v- rel oncogene but also on intracellular factor(s) whose expression varies according to the state of T cell physiology and/or activation.     

Isotope dilution tandem mass spectrometric method for T4/T3

BACKGROUND: The thyroid hormones thyroxine (T4) and 3,5,3'-triidothyronine (T3) are essential for regulating a number of biological processes, including growth, neurodevelopment, carbohydrate metabolism, oxygen consumption and protein synthesis. Immunoassays are the current methods for thyroid hormone measurement and suffer from a lack of specificity. Our objective was to simultaneously measure T4 and T3 using isotope dilution tandem mass spectrometry within a single run. To compare the results obtained by this MS/MS method with those obtained by an immunoassay procedure on the same samples (DPC Immulite for T3, Diagnostics Product, and Dade RxL Dimension for T4, Dade-Behring). METHODS: An API-3000 tandem mass spectrometer (SCIEX, Toronto, Canada) equipped with TurboIonSpray and Shimadzu HPLC system was used employing isotope dilution with deuterium-labeled internal standard (l-thyroxin-d2). The method requires 100 microl of serum and involves addition of internal standard, precipitation of proteins with methanol and injection of the supernatant onto a C-18 column. After washing, the switch valve is activated and T4 and T3 eluted using a methanol gradient. T4 and T3 by immunoassay were performed using the Dade RxL Dimension and the DPC Immulite, respectively. RESULTS AND CONCLUSIONS: An isotope dilution tandem mass spectrometry method for the simultaneous determination of total T4 and T3 in serum is described which is accurate, specific, precise (%CVs 3.5-9.0), simple and fast (<7 min).     

Antibody-induced modulation of the CD3/T cell receptor complex causes T cell refractoriness by inhibiting the early metabolic steps involved in T cell activation

We investigated the mechanism involved in T cell unresponsiveness that follows the monoclonal antibody-induced surface modulation of the CD3-TCR complex. We determined whether modulation of CD3-TCR affected the early metabolic steps such as [Ca2+]i rise and InsP3 formation. A strong inhibition of the increase on [Ca2+]i mediated by either anti-TCR or anti-CD2 mAbs was detected. In contrast, surface modulation of CD2 molecules did not prevent the [Ca2+]i increase induced by anti-TCR mAb. Similarly, InsP3 increase was strongly reduced only after modulation of CD3-TCR complex (but not of CD2 molecules). Therefore, it appears that surface modulation of CD3-TCR complex causes T cell refractoriness by inhibiting the very early metabolic events that follow receptor-ligand interactions.     

先兆流产孕妇Th1／Th2细胞因子平衡状况分析

目的探讨辅助T细胞1（Th1）、辅助T细胞2（Th2）型细胞因子平衡与正常妊娠及先兆流产之间的关系。方法采用酶联免疫吸附试验（ELISA）检测60例先兆流产妇女和42名正常妊娠妇女血清中Th1型细胞因子（IL-2、TNF-α及Th2型细胞因子（IL4、IL-10）的表达水平。结果与正常妊娠组相比,先兆流产组血清中IL-2和TNF-α的表达水平明显升高（P均〈0．05）;而2组之间IL-4和IL-10的表达水平差异无统计学意义（P〉0．05）。Th1型细胞因子与Th2型细胞因子平衡向Th1的方向移动。结论Th1／Th2型细胞因子的病理性失衡可能与先兆流产的发生有-定关系。