肝硬化患者外周血单个核细胞TLR4表达及其基因多态性的研究

目的：检测肝硬化及其不同Child分级患者外周血单个核细胞(PBMCs)Toll样受体4（TLR4）表达，分析TLR4基因Asp299Gly、Thr399Ile的多态性及其与肝硬化疾病发生的相关性。方法:分离110例汉族乙肝后肝硬化患者与健康对照者静脉抗凝血的PBMCs，流式细胞、实时荧光定量PCR及PCR-限制性片段长度多态性分别检测PBMCs TLR4蛋白、 mRNA及Asp299Gly、Thr399Ile基因多态性，分析TLR4基因多态性与肝硬化发生的相关性。结果:肝硬化组PBMCs TLR4阳性细胞率与mRNA表达正相关，均显著高于对照组(P<0.01)，且随着Child评分的升高而升高(P<0.01)；但220例受试对象均未检测到TLR4基因Asp299Gly、Thr399Ile的突变型。结论:乙肝后肝硬化患者PBMCs TLR4表达水平明显增高，与肝硬化损伤的严重程度相关；TLR4基因Asp299Gly、Thr399Ile多态性在中国汉族人群中出现频率低，且与肝硬化疾病的易感性可能无关。     

TLR4 Asp299Gly、Thr399Ile基因多态性对变应性哮喘的发病及IgE水平的影响

目的　探讨TLR4 (toll likereceptor 4 )Asp2 99Gly、Thr399Ile基因多态性对变应性哮喘的发病和血浆IgE水平的影响。方法　利用聚合酶链反应 限制性片段长度多态性分析技术 (PCR RFLP) ,对 1 97例变应性哮喘患者和 1 5 6例健康人进行TLR4的Asp2 99Gly、Thr399Ile两位点的基因型检测。同时利用免疫发光法检测血浆IgE的水平。结果　 1 97例变应性哮喘患者TLR4基因Asp2 99Gly位点Asp Asp、Asp Gly和Gly Gly的基因型频率为 0 .81 7、0 .1 4 7和 0 .0 36 ,与正常对照组相比差异无统计学意义 (χ2 =0 .0 32 ,P =0 .984 ) ;但变应性哮喘患者Gly Gly、Asp Gly基因型血浆总IgE对数值 ( x±s:2 .6 1 5± 0 .6 0 0 1 ,n =36 )与Asp Asp基因型血浆总IgE对数值 ( x±s:2 .2 4 0± 0 .6 894 ,n =1 6 1 )相比较高 ,差异有统计学意义 (P =0 .0 0 2 )。TLR4基因Thr399Ile位点Thr Thr、Thr Ile和Ile Ile的基因型频率为 0 .970、0 .0 2 0和 0 .0 1 0 ,与正常对照组相比差异无统计学意义 (χ2 =0 .6 2 0 ,P =0 .733) ;变应性哮喘患者Ile Ile、Thr Ile基因型血浆总IgE对数值 ( x±s:2 .4 1 7± 0 .4 4 2 3,n =6 )与Thr Thr基因型血浆总IgE对数值 ( x±s:2 .30 5± 0 .6 94 9,n =1 91 )相比差异无统计学意义 (P =0 .5 71 )。     

Toll样受体4多态性与强直性脊柱炎易感性的荟萃分析

目的 用荟萃分析方法评价toll样受体(TLR)4基因多态性与强直性脊柱炎的关系. 方法 检索在2007年2月前在PubMed及中国期刊全文数据库发表的中英文献.用RevMan 4.2对纳入文献进行荟萃分析,评价合并效应量、功效、异质性及发表偏倚. 结果 共纳入4篇有关Asp299Gly多态位点和3篇Thr399Ile多态位点的病例对照研究.未发现异质性及发表偏倚,合并后功效在80%左右.Asp299Gly位点合并效应量OR=0.94(95%CI:0.66～1.35),Thr399Ile位点合并效应量OR=1.08(95%CI:0.70～1.65). 结论 TLR4基因不是强直性脊柱炎的主要易感基因.     

CD14、TLR4 基因多态性与百色地区原住壮族人群脊柱结核易感关联性 研究

目的:研究脂多糖受体(CD14)和Toll样受体4(TLR4)基因多态性在壮族人群的分布特征及其与脊柱结核易感性的关系。方法:2011年1月至2017年12月期间右江民族学院附属医院就诊的百色地区原住壮族人群脊柱结核患者60例、肺结核患者60例和健康对照组60例三组人群,用A测序法测定三组人群的TLR4基因序列和CD14基因序列,比较三组人群CD14、TLR4基因多态位点的基因型频率和等位基因频率。结果:TLR4基因Asp299Gly和Thr399 Ile位点在壮族人群脊柱结核患者和肺结核患者均未发现呈多态性分布。壮族人群均发现CD14/-159呈多态性,以TT基因型为主,CD14基因C-159T和G-1145A等位基因频率按Hard-Weiber平衡吻合度检验,脊柱结核组、肺结核组和健康对照组三组含有T等位基因携带者的基因型频率和等位基因频率分布两两比较有统计学显著性差异(χ~2=8.462,P=0.004;χ~2=5.432,P=0.025;χ~2=7.321,P=0.021)。结论:百色地区壮族脊柱结核患者和肺结核患者未发现TLR4基因Asp299Gly和Thr399Ile多态性;百色地区壮族人群脊柱结核患者和肺结核患者存在CD14/-159多态性,以TT为主,CD14基因-159TT和-1145AA基因型可能为百色地区原住壮族人群脊柱结核病的易感高风险因子。     

冠心病患者内皮脂肪酶基因Thr111Ile和Gly26Ser多态性与脂蛋白代谢的关系

目的: 探讨冠心病（CHD）患者内皮脂肪酶基因（LIPG）Thr111Ile和Gly26Ser 的多态性与脂蛋白代谢的关系。 方法: 438例冠状动脉造影患者，根据造影结果分为CHD组（242例）和对照组（196 例）。应用酶法测定患者的总胆固醇（TC）、甘油三酯（TG）、高密度脂蛋白胆固醇（HDL-c）、低密度脂蛋白胆固醇（LDL-c）水平。同时应用聚合酶链反应-限制性内切酶片段长度多态性（PCR-RELP）核苷酸分型技术检测Thr111Ile和Gly26Ser多态性，进行统计学分析。 结果: Thr111Ile在本研究人群中的基因频率分布为CC 76.7％、CT 23.3％、TT 0.0％，等位基因频率为C 88.3％、T 11.7%。CT组HDL-c水平高于CC组（P<0.05），经多因素逻辑回归分析，CT基因仍与高HDL-c水平呈显著相关（P<0.05），CHD与Thr111Ile多态性无显著相关（P>0.05）。未发现Gly26Ser基因变异。结论: 中国汉族人群中存在LIPG基因的Thr111Ile多态性。Thr111Ile多态性中的CT基因致HDL-c水平升高，但未发现其与CHD直接相关。本研究未发现Gly26Ser多态性。     

广东汉族正常人群TLR4基因单核苷酸多态性研究(英)

目的：人类Toll样受体4（TLR4）是先天免疫系统中一个重要的病原微生物识别受体。本研究将建立中国汉族正常人群TLR4基因座位的单核苷酸多态性图谱。方法：收集191例健康、无亲缘关系的中国广东汉族人外周血液,通过对TLR4基因的启动子区、3个外显子区以及它们周围的内含子区进行PCR扩增和测序,得到汉族正常人群TLR4基因座位单核苷酸多态性图谱及其频率分布特点。结果：共发现8个单核苷酸多态性位点,其中5个是首次发现的新位点。分布频率最高（0.283）的单核苷酸多态性位点是-1607 C/T。常见于高加索人中的2个非同义突变Asp299Gly和Thr399Ile在汉族人中没有被发现。中性检验显示汉族人群TLR4基因符合中性进化模型。结论：本研究建立了汉族正常人群TLR4基因座位的单核苷酸多态性图谱,发现了一些种族特异性的单核苷酸多态性位点,这些工作将为今后开展汉族人基因多态性与疾病相关性研究以及人群进化研究提供一定的帮助。     

抗原处理相关运载体等位基因与I型糖尿病的关联研究

目的 :探讨抗原处理相关运载体 (transporterassociatedwithantigenprocessing ,TAP)等位基因与I型糖尿病 (DM1)的关联性。方法 :用聚合酶链反应 序列特异性寡核苷酸探针杂交技术 ,对 5 2例DM1患者及 6 1例正常对照人群进行TAP1、TAP2等位基因变异位点氨基酸表型频率分析。结果 :DM1患者TAP1333位Ile Ile、6 37位Asp Asp、TAP2 379位Val Val纯合子表型频率显著低于对照 (P <0 0 0 5 ) ,DM1患者TAP1333位Ile Val、6 37位Asp Gly、TAP2 379位Ile Val杂合子表型频率明显高于对照 (P <0 0 0 5 )。TAP基因的其它变异位点氨基酸表型频率在DM1患者与正常对照组之间的差异无显著性意义。结论 :TAP1333位Ile Ile、6 37位Asp Asp、TAP2 379位Val Val纯合子表型可能是DM1的保护基因。TAP1333位Ile Val、6 37位Asp Gly、TAP2 379位Ile Val杂合子表型可能是DM1的易感基因     

子宫内膜异位症与女性生育力的相关性分析

目的：探讨子宫内膜异位症与女性生育力的相关性。方法对我院于近年收治的子宫内膜异位症患者中87例已婚育龄女性作为研究对象,根据子宫内膜异位症分期表对患者进行分期并统计治疗前后妊娠率,分析子宫内膜异位症与女性妊娠的关系。结果本组患者中Ⅰ期占39.1%,Ⅱ期占18.4%,Ⅲ期占27.8%,Ⅳ期占14.9%。不同分期的患者经治疗后,妊娠率均得到明显提高,并具有显著差异(P<0.05)。结论随着子宫内膜异位症分期级别升高女性不育风险增大,在对子宫内膜异位症患者进行治疗后,不同分期患者妊娠率均有显著提高。     

小肠脂肪酸结合蛋白基因与2型糖尿病相关性研究

目的　探讨中国人群中小肠脂肪酸结合蛋白 (FABP2 )基因 Ala5 4 Thr多态性与 2型糖尿病的相关性。方法　采用聚合酶链反应 -寡核苷酸连接测定方法对北京地区 10 2对病例 -对照配偶对进行FABP2基因 Ala5 4 Thr多态性基因型检测。结果　对照组中携带 Thr/ Thr纯合子基因型组血清脂蛋白 a(L pa)水平高于 Ala/ Ala纯合子组 (P<0 .0 5 ) ;Thr5 4 Thr纯合子基因型组患 2型糖尿病的危险性较Ala5 4 Ala纯合子组高 ,但差异无显著性 (Thr/ Thr vs Ala/ Ala,调整 OR=2 .94 ;95 % CI:0 .93～ 9.32 ,P=0 .0 6 7)。结论　在中国汉族人群中 ,FABP2基因 Ala5 4 Thr多态性与血清 L pa水平相关 ,但不是 2型糖尿病的主要致病基因     

CYPl7、CYPlA2酶基因多态性与子宫内膜异位症的关系

目的探讨CYPl7 T-34C、CYPIA2 G-2964A基因多态性与子宫内膜异位症遗传易感性的关系。方法抽取108例确诊为子宫内膜异位症患者及84例对照组女性的静脉血,提取全基因组DNA,分别用聚合酶链式反应（PCR）技术扩增CYPl7 T-34C、CYPIA2 G-2964A多态位点的基因片段,并对其进行酶切,根据酶切结果计算出各等位基因的表型频率,用X2检验及OR值分析其多态性与子宫内膜异位症的关系。结果病例组和对照组CYPl7基因的基因型及等位基因的频率分布比较差异有统计学意义（P〈O.05）。病例组和对照组CYPIA2基因型、等位基因频率的比较差异无统计学意义（P〉0.05）。结论CYPl7 T-34C可能与III、IV期子宫内膜异位症发病风险相关。CYPlA2 G-2964A多态性可能不是子宫内膜异位症独立的危险因素。     

Common human Toll-like receptor 4 polymorphisms--role in susceptibility to respiratory syncytial virus infection and functional immunological relevance

Evidence suggests that Toll-like receptor 4 (TLR4) contributes to immune recognition of respiratory syncytial virus (RSV). The TLR4 gene harbours a polymorphism-Asp299Gly-previously associated with reduced TLR4 signalling. To understand of how host genetic variation influences the outcome of RSV infection in children, we examined the association between the TLR4 299Gly allele and severe RSV disease. By genotyping 236 children with RSV infection and 219 healthy controls we found no association between the risk of severe RSV infection and Asp299Gly polymorphisms (P>0.05), and we demonstrate that the TLR4 Asp299Gly genotype does not influence susceptibility to either RSV serotype A or B (P>0.05). Finally, examining the functional impact of the TLR4 Asp299Gly polymorphism (n=58), we demonstrate that proinflammatory cytokine production following TLR4 activation was indistinguishable between homozygous (Asp/Asp) and heterozygous (Asp/Gly) subjects. We conclude that the Asp299Gly TLR4 polymorphism does not alter receptor function and does not influence the risk of severe RSV infection.     

Effect of the functional toll-like receptor 4 Asp299Gly polymorphism on susceptibility to late-onset Alzheimer's disease

Experimental data have shown an upregulated expression of toll-like receptors, particularly toll-like receptor 4 (TLR4), in neurodegeneration. The Asp299Gly polymorphism of the TLR4 gene has been associated with an attenuated receptor signalling and a blunted inflammatory response. In the present study, we sought to determine whether this common genetic variant could influence susceptibility to late-onset Alzheimer's disease (LOAD) in an Italian population sample. A cohort of 277 LOAD patients and 300 cognitively healthy controls were genotyped for the TLR4 Asp299Gly polymorphism using restriction isotyping. The frequency of the minor 299Gly allele was significantly higher in the controls than in the LOAD cases (7.2% versus 3.1%, respectively, P=0.003). Additionally, the frequency of the variant genotypes (Asp/Gly and Gly/Gly) was 13.0% in the controls and 5.4% in LOAD patients (P=0.002). After adjustment for age, gender, and the APOE varepsilon4 carrier status, the odds ratio for the development of LOAD associated with the Asp/Gly and Gly/Gly versus Asp/Asp genotype was 0.37 (95% CI: 0.20-0.69, P=0.002). Our data further support a role for innate immunity in neurodegeneration and give the first evidence that the TLR4 Asp299Gly variant may be protective toward the development of LOAD.     

Microsatelite GT polymorphism in the toll-like receptor 2 is associated with colorectal cancer

Factors underlying genetic predisposition for development of sporadic colorectal cancer are largely unknown. The fact that this cancer is more common in patients suffering from inflammatory bowel disease raises the question of the relationship between chronic inflammation and cancer. Toll-like receptors 2 (TLR2) and 4 (TLR4) are critical in initiating innate immune response and inflammation toward various bacteria commonly found in the intestine. Recent evidence about the association of polymorphisms in these genes with ulcerative colitis and Crohn's disease, as well as other inflammatory conditions, was the basis for our investigation of their role in sporadic colorectal cancer. We assessed genotype and allele frequencies of TLR2 GT microsatelite polymorphism, TLR2 Arg753Gln, TLR4 Asp299Gly and TLR4 Thr399Ile polymorphisms in 89 colorectal cancer patients and 88 age- and sex-matched controls. The frequency of TLR2 GT microsatelite alleles with 20 and 21 GT repeats was decreased (p = 0.0044 and p = 0.001, respectively), while the frequency of the allele with 31 GT repeats was increased (p = 0.0147) in patients. The mutant allele Asp299Gly of TLR4 gene was slightly more frequent in colorectal cancer patients (p = 0.0269). In conclusion, we report an association of microsatelite GT polymorphisms of TLR2 gene and Asp299Gly polymorphism of the TLR4 gene with sporadic colorectal cancer among Croatians.     

Toll-like receptor (TLR) 2 and 4 mutations in periodontal disease

Toll-like receptors (TLR) are signal molecules essential for the cellular response to bacterial cell wall components. Different functional effective polymorphisms for the TLR 4 gene (Asp299Gly; Thr399Ile) and for the TLR 2 gene (Arg677Trp, Arg753Gln) have recently been described that are associated with impaired lipopolysaccharide signal transduction. A total of 122 patients with chronic periodontal disease and 122 healthy unrelated controls were genotyped for the Asp299Gly and Thr399Ile polymorphism of the TLR 4 gene and the Arg677Trp and Arg753Gln mutation of the TLR 2 gene. The mutations were identified with polymerase chain reaction followed by restriction fragment length polymorphism (RFLP) analysis. The prevalence of the Asp299Gly and the Thr399Ile mutant allele was 4.1% (10/244) and 4.5% (11/244) among periodontitis patients. For the healthy controls the prevalence was 3.3% (8/244) for the Asp299Gly (P = 0.810) and 3.7% (9/244) for the Thr399Ile mutant allele (P = 0.819). The Arg753Gln mutant allele was found in 2.9% (7/244) of the periodontitis subjects as compared to 4.1% (10/244) in the control group (P = 0.622). The Arg677Trp mutant allele was not found in any of the study subjects. Unlike in ulcerative colitis there was not observed an association between chronic periodontitis and the various mutations of the TLR 2 and 4 gene.     

Toll-like receptor (TLR) 4 polymorphisms are associated with a chronic course of sarcoidosis

The aetiology of sarcoidosis, an inflammatory granulomatous multi-system disorder, is unclear. It is thought to be the product of an unknown exogenous antigenic stimulus and an endogenous genetic susceptibility. Toll-like receptors (TLR) are signal molecules essential for the cellular response to bacterial cell wall components. Lipopolysaccharide (LPS), for example, binds to TLR 4. Two different polymorphisms for the TLR4 gene (Asp299Gly and Thr399Ile) have been described recently. This leads to a change in the extracellular matrix function of TLR4 and to impaired LPS signal transduction. We genotyped a total of 141 Caucasian patients with sarcoidosis and 141 healthy unrelated controls for the Asp299Gly and Thr399Ile polymorphisms in the TLR4 gene. The mutations were identified with polymerase chain reaction followed by restriction fragment length polymorphism (RFLP) analysis. Among sarcoidosis patients the prevalence for each Asp299Gly and Thr399Ile mutant allele was 15.6% (22/141). In the control group the prevalence was 5.67% (8/141) (P = 0.07). In the subgroup of patients with acute sarcoidosis there was no difference in the control group (P = 0.93), but there was a highly significant association between patients with a chronic course of sarcoidosis and TLR4 gene polymorphisms (P = 0.01).     

Role of TLR4 C>1196T (Thr399Ile) and TLR4 A>896G (Asp299Gly) polymorphisms in a North Indian population with asthma: a case‐control study

Toll‐like receptor 4 (TLR4) is the most important TLR among the pattern recognition receptors which recognizes lipopolysaccharide of gram‐negative bacteria. They identify a highly conserved structure of microbes called pathogen‐associated molecular patterns and activate immune and inflammatory responses that have been shown to be involved in the pathogenesis of asthma. The role of TLR4 gene polymorphisms in asthma was detected in a total of 964 individuals, including 483 healthy controls and 481 asthma patients from a North Indian population. The genotyping was carried out using polymerase chain reaction–restriction fragment length polymorphism method. Statistical analysis revealed that the heterozygous genotype as well as the mutant (T) allele of the TLR4 C>1196T (Thr399Ile) polymorphism shows resistance towards asthma with OR = 0.70, 95% CI (0.49–0.99), P corrected value = 0.046 and OR = 0.72, 95% CI (0.52–0.98), P corrected value = 0.039, respectively. However, no association was found between the TLR4 A>896G (Asp299Gly) polymorphism and asthma patients (P > 0.05). This is the first study conducted in India conferring TLR4 (Thr399Ile) polymorphism resistance towards asthma, while lack of association was found between TLR4 (Asp299Gly) polymorphism and asthma in the studied North Indian population.     

Single step high-throughput determination of Toll-like receptor 4 polymorphisms

BACKGROUND: Toll-like receptors are central components of host defence in humans, responsible for recognition of pathogen-associated molecular patterns and activation of innate immunity. Toll-like receptor 4 (TLR4) is activated by lipopolysaccharide (LPS) and other microbial components, thereby initiating the expression and release of pro-inflammatory cytokines. The common, frequently co-segregating allelic variants Asp299Gly and Thr399Ile have been related to susceptibility to gram-negative infections and sepsis and may be involved in the development of atherosclerosis. Identification of TLR4 Asp299Gly and Thr399Ile genotypes can be important for examination of genotype/phenotype relationships as well as for individual risk assessment of patients. METHODS: TLR4 Asp299Gly and Thr399Ile genotypes were detected by a single tube polymerase chain reaction (PCR), based on exonuclease degradation of dual labelled allele-specific oligonucleotides. The assay results were compared with conventional restriction fragment length polymorphism (RFLP) analysis. RESULTS: Genotypes of 345 individuals were determined simultaneously in a single PCR assay. Allele frequencies for our population were 6.8% for the TLR4 Asp299Gly polymorphism and 6.4% for the Thr399Ile polymorphism. Validation by RFLP analysis revealed a correct detection of all genotypes. CONCLUSIONS: We have developed a novel method for the detection of the TLR4 Asp299Gly and Thr399Ile mutations, permitting rapid genotyping which should be useful for large-scale population studies as well as applicable for routine clinical testing.     

Polymorphisms of toll-like receptor 2 and 4 genes in rheumatoid arthritis and systemic lupus erythematosus

Human toll-like receptors (TLRs) participate in the innate response and signal the activation of adaptive immunity. Therefore, these TLRs may be important in autoimmune diseases such as rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). We investigated, by using a polymerase chain reaction restriction-fragment length polymorphism method, the possible association between the polymorphisms of TLR2 (Arg677Trp and Arg753Gln) and TLR4 (Asp299Gly and Thr399Ile) genes with the susceptibility or severity of RA and SLE. Our study population consisted of 122 patients with SLE, 224 patients with RA, and a control group of 199 healthy individuals. The TLR2 polymorphisms were very rare in our population; no individual carrying the TLR2-Arg677Trp polymorphism was observed, whereas the TLR2-Arg753Gln polymorphism was present in only 1% of the total population. We found no statistically significant differences in the TLR4-Asp299Gly and the TLR4-Thr399Ile genotype or allele distribution between SLE patients, RA patients, and control individuals. Similarly, no association was found with any of the demographic and clinical parameters tested either in RA or in SLE patients. In conclusion, a case-control study was used to analyze, for the first time, the influence of TLR2 and TLR4 gene polymorphism on the predisposition and clinical characteristics of SLE and RA but provided no evidence for association of TLR2 or TLR4 gene polymorphism with either disease in the population under study.     

Rarity of TLR4 Asp299Gly and Thr399Ile polymorphisms in the Korean population

PURPOSE: Activation of the innate immune system and chronic low-grade inflammation are thought to be involved in the pathogenesis of atherosclerosis and also thought to be associated with type 2 diabetes and its complications. As a receptor for bacterial lipopolysaccharide and heat-shock proteins, Toll-like receptor 4 (TLR4) is one of the central regulators of the immune response. Recent studies have reported an association between TLR4 polymorphisms and diabetes and its complications in Caucasian populations. MATERIALS AND METHODS: In this study, we analyzed the association between TLR4 gene polymorphisms in patients with features of type 2 diabetes and healthy controls in Korea. Two polymorphisms of the TLR4 gene (Asp299Gly and Thr399Ile) were examined in 225 diabetic patients and 153 healthy controls using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and single-strand conformation polymorphism (SSCP). RESULTS: No Asp299Gly or Thr399Ile mutations were detected in any of the 378 subjects. Seven subjects from each group who had slightly different SSCP patterns were selected for sequencing, but we found no TLR4 polymorphisms on Exon3. The Asp299Gly and Thr399Ile TLR4 gene polymorphisms were absent in both groups, which was similar to the results for Japanese and Chinese Han subjects. CONCLUSION: Our data and other Asian data suggest that a racial difference can be found in the frequency of the TLR4 polymorphism.