TLR4基因多态性与慢性胃炎幽门螺杆菌感染无相关性

目的:研究我国湖北汉族人群TLR4基因 Asp299Gly多态性与慢性浅表性胃炎及幽门螺杆(H pylori)感染的关系．方法:采用病例-对照研究和多聚酶链反应-限制性片段长度多态性(PCR-RFLP)方法,检测 115例慢性浅表性胃炎患者115例和正常对照者2644例的TLR4等位基因Asp299Gly基因型分布．结果:慢性浅表性胃炎患者的H pylori阳性率 89．6％,显著高于正常对照组61．7％(P<0．000 1, OR=5．319．95％CI:2．784-10．162)．在H pylori 感染相关性的慢性胃炎组和正常对照组中 TLR4基因Asp299Gly基因型所有个体均为 AA纯合子,未发现的突变型,其基因型、等位基因以及携带者频率总体分布无显著性差异．结论:TLR4基因Asp299Gly基因多态性与H pylori相性慢性胃炎无明显相关性．     

TLR2、TLR4和NOD2/CARD15基因多态性与溃疡性结肠炎相关性的meta分析

背景:近年我国溃疡性结肠炎(UC)的患病率明显增高,Toll样受体2(TLR2)、TLR4和NOD2/CARD15基因多态性与UC的发生、发展可能密切相关。目的:探讨TLR2、TLR4和NOD2/CARD15基因多态性对UC发生的影响。方法:计算机检索Pub Med、中国生物医学文献、中国知网、万方数据库、重庆维普等数据库中所有TLR2、TLR4和NOD2/CARD15基因多态性与UC相关性的研究。按照纳入与排除标准筛选文献、评价质量并提取数据,采用Rev Man 5.3软件进行meta分析。结果:共纳入15项研究。Meta分析结果显示,TLR2 Arg753Gln基因多态性与UC发生风险无关(P 0.05)。除隐性模型外,TLR4 Asp299Gly基因多态性可显著增加UC的发生风险(P 0.05),TLR4 Thr399Ile基因超显性模型可导致UC风险增加(P 0.05),但显性模型和隐性模型与UC无关(P 0.05)。NOD2/CARD15(Arg702Trp、Gly908Arg、Leu1007fsins C)基因多态性均与UC无关(P 0.05)。结论:NOD2/CARD15(Arg702Trp、Gly908Arg、Leu1007fsins C)、TLR2(Arg753Gln)与UC发生风险无关,TLR4(Asp299Gly、Thr399Ile)可增加UC的发生风险。     

CD14及Toll样受体4基因多态性与大肠癌的相关性研究

目的探讨我国湖北汉族人Toll样受体（TLR）4基因Asp299Gly和CD14 C-260T基因多态性分布与大肠癌的相关性。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110例大肠癌患者及160例正常对照者TLR4基因Asp299Gly及CD14 C-260T基因型及等位基因频率的分布。结果大肠癌组CD14 C-260T基因型与正常对照组比较，差异有统计学意义（P〈0．05）。正常对照组CC基因型的频率为15．6%，明显低于大肠癌组的31．8％（P=0．0027，OR=0．3968，95％CI=0．2209～0．7129）；正常对照组中CT基因型的频率为48．1％，明显高于大肠癌组的30．9％（P=0．0056，OR=2．074，95%CI=1．246～3．452）。所有样本中均未发现TLR4基因Asp299Gly的突变型。结论CD14 C-260T基因多态性与中国湖北汉族大肠癌显著相关，而TLR4基因Asp299Gly多态性与大肠癌无关。     

浙江汉族人群Toll样受体4基因多态性与幽门螺杆菌相关消化性溃疡的关系

背景：幽门螺杆菌（H.pylori）感染是消化性溃疡的主要病因,然而其致病性存在个体差异,可能与宿主遗传易感性和先天性免疫机制有关。Toll样受体（TLR）在机体的先天性抗感染免疫中起重要作用。目的：探讨浙江汉族人群TLR4基因Asp299Gly多态性与H.pylori相关消化性溃疡的关系。方法：以聚合酶链反应-限制性片段长度多态性（PCR-RFLP）方法检测118例浙江汉族消化性溃疡患者和210名健康对照者的TLR4基因Asp299Gly等位基因和基因型;行快速尿素酶试验和血清H.pyloriIgG检测判断H.pylori感染情况。结果：本组浙江汉族人群TLR4基因Asp299Gly均为AA纯合子基因型,未见突变基因型AG和GG。消化性溃疡组H.pylori感染率为94.9%,显著高于正常对照组的62.4%（P=0.000）;两组Asp299Gly基因型频率差异无统计学意义。结论：浙江汉族人群TLR4基因Asp299Gly多态性与H.pylori相关消化性溃疡无相关性。     

Toll样受体及其基因多态性与感染性疾病关系的研究进展

Toll样受体是近年来发现的跨膜信号传递受体,他作为一种重要的模式识别受体(PRRs)在先天免疫中通过对病原体相关的分子模式(PAMPs)的识别发挥作用,通过刺激信号的级联反应诱导炎症因子和细胞因子产生,在抗感染中起重要作用.基因多态性影响机体对疾病的遗传易感性,TLRs的位点多态性与炎性应答损伤和感染性疾病的遗传易感性相关.目前多数研究表明TLR4的Asp299Gly和Thr399Ile,TLR2的Arg753Gln和Arg667Trp多态性与感染性疾病的发生相关,其他TLRs的基因多态性也有研究.本文就TLRs家族的功能及其基因多态性与感染性疾病的关系作一综述.     

Toll样受体4基因多态性与消化性溃疡和幽门螺杆菌感染的相关性研究

背景：幽门螺杆菌（H．pylori）感染是消化性溃疡的主要病因。脂多糖（LPS）通过TOU样受体（TLR）4激活核因子（NF）-KB，在抗感染免疫应答中起启动和调节作用。TLR4基因发生Asp299Gly突变可中断TLR4介导LPS信号传导。目的：研究我国湖北省汉族人群TLR4基因Asp299Gly多态性与消化性溃疡和肌pylori感染的关系。方法：采用病例对照研究和聚合酶链反应-限制性片段长度多态性（PCR-RFLP）法．检测126例消化性溃疡患者和264名正常对照者的TLR4等位基因Asp299Gly基因型分布。结果：消化性溃疡者肌pylori阳性率（90．5％）显著高于正常对照组（61．7％）（P〈0．0001，OR=5．889，95％CI：3．089-11．216）。在H．pylori感染相关性消化性溃疡组和正常对照组中均未发现TLR4基因Asp299Gly的突变型，其基因型、等位基因以及携带者频率总体分布无显著性差异。结论：本研究未能显示TLR4基因Asp299Gly基因多态性与H.pylori感染、H．pylori相关性消化性溃疡形成有相关性。     

类风湿关节炎与TLR4单核苷酸多态性关联研究的Meta分析

目的探讨类风湿关节炎(RA)与TLR4基因Asp299Gly多态性的关联情况。方法检索已发表的有关RA和TLR4基因Asp299Gly多态性的文献．进行Meta分析。结果3项研究共纳入718例RA患者和1392名正常对照，综合分析显示TLR4基因Asp299Gly多态性不是RA的关联基因，OR=1．23(0．67，2．25)，P=0．5；TLR4基因Asp299Gly多态性分布在男女性RA患者分布差异无统计学意义，OR=0．48(0．22．1．03)，P=0．06：在共同表位基因阳性和阴性患者组差异无统计学意义，OR=0．67(0．40，1．13)，P=0．13；在类风湿因子(RF)阳性和阴性患者组差异无统计学意义，OR=I．02(0．51，2．02)，P=-I；RA患者中，Asp299Asp基因型患者发病早于Asp299Gly基因型者，OR=-4．35(-7．45，-1．25)，P=0．006。结论Meta分析显示，TLR4基因Asp299Gly多态性与RA易感性无关联．但Asp299Asp基因型者起病早于Asp299Gly基因型者。应在东方人群进一步开展随机对照和前瞻的队列研究揭示其在RA发病中的作用。     

TLR4和TNF-α基因多态性与支气管哮喘的相关性研究

目的探讨Toll样受体4和肿瘤坏死因子-α基因多态性与支气管哮喘的关系。方法采用病例对照研究和PCR-DNA测序的方法,检测50例支气管哮喘患者和30例对照组的TLR4的Asp299Gly和TNF-308的基因多态性。结果 （1）在支气管哮喘和健康对照组间,未发现TLR4Asp299Gly突变型。（2）支气管哮喘和正常对照组间未发现存在TNF-308G-A替换多态性。结论 （1）TLR4Asp299Gly基因多态性与支气管哮喘的易感性不相关,TNF-α基因多态性与支气管哮喘的易感性无相关性。     

海南汉族2型糖尿病患者胰岛素受体底物1基因Gly972Arg多态性的研究

目的 研究胰岛素受体底物1（IRS。1）基因Gly972Argr矢变与海南汉族2型糖尿病（T2DM）的关系。方法应用聚合酶链反应-限制性片段长度多态性技术对海南汉族60例T2DM患者和60例糖耐量正常人群进行IRS-1基因Gly972Arg突变位点基因型检测。结果T2DM组IRS-1基因Gly972Arg突变频率13．3％,对照组IRS-1基因Gly972Arg突变频率3．3％,两者比较有统计学差异（r=7．2,P〈0．01）。结论IRS—1基因Gly972Arg突变可能与海南汉族T2DM的发生有相关性。     

胰岛素受体底物1基因Gly972Arg多态性与2型糖尿病不相关

目的：探讨中国汉族人群胰岛素受体底物1（IRS－1）基因Gly972Arg多态性与2型糖尿病的关系。方法：选取102例2型糖尿病患者及102例糖耐量正常的患者配偶进行对照研究，应用聚合酶链反应－－限制性片断长度多态性的方法进行胰岛素受体底物1基因Gly972Arg多态性位点基因型检测。结果：IRS－1基因Gly972Arg突变频率在病例组和对照组均为2％，明显低于白人。结论：在中国汉族人群中，IRS－1基因Gly972Arg突变不是2型糖尿病的主要致病因素。     

The lack of genetic association of the Toll-like receptor 2 (TLR2) Arg753Gln and Arg677Trp polymorphisms with rheumatic heart disease

Acute rheumatic fever (ARF) is a non-suppurative inflammatory disease after group A, beta haemolytic streptococcal pharyngitis. Certain individuals can develop ARF. This finding implies variability in host predisposition to ARF. A variety of studies have linked specific genetic markers with ARF or rheumatic heart disease (RHD) as a sequelae of ARF. For this purpose, we aimed to search the role of polymorphisms in Toll-like receptor-2 and -4 (TLR2 and TLR4) gene in Turkish patients with RHD. This study included a total 84 patients with RHD, ages ranging between 18 and 65, 25 male and 59 female, fulfilling the revised classification criteria of Jones. One hundred forty healthy unrelated persons were selected as a control group. Genotype analysis: DNA was extracted from whole blood. TLR4 gene (Asp 299Gly and Thr399Ile) and TLR2 gene (Arg753Gln and Arg677Trp) polymorphisms were genotyped by the previously reported method. Statistical analysis: binary logistic regression models were used. Results were expressed as odds ratios (OR) with corresponding 95% confidence intervals (95% CI). Significant level was predefined at 0.05. There was a significant difference for carrying Ile allele in the 399 position in the patients compared to healthy controls (OR = 5.26, 95% CI, 1.40-19.73, p = 0.014). In the TLR4 gene, Asp 299Gly polymorphism did not reach to a statistically significant value (OR = 3.02). We found no Arg753Gln polymorphism of the TLR2 gene in the patient group. There were three heterozygote samples in the healthy group. We did not detect Arg677Trp polymorphism of the TLR2 gene in both patient and control groups.     

Lack of association of single nucleotide polymorphisms in toll-like receptors 2 and 4 with enthesitis-related arthritis category of juvenile idiopathic arthritis in Indian population

Toll-like receptors 2 and 4 are over expressed in patients with enthesitis-related arthritis and cause increased production of pro-inflammatory cytokines. This aberrant functioning could be due to polymorphisms in TLR2 and TLR4. Hence, we genotyped ERA patients for Arg753Gln and Arg677Trp polymorphism in TLR2 gene and Asp299Gly and Thr399Ile polymorphism in TLR4 gene. DNA was extracted from blood from ERA patients and healthy controls. All four polymorphisms were studied by PCR–RFLP method. 200 healthy controls and 97 ERA patients were enrolled. All healthy controls and patients had wild-type allele for Arg753Gln and Arg677Trp TLR2 polymorphism. Regarding TLR4, Asp299Gly polymorphism A allele frequency was 90 % in controls and 96 % in patients (OR 2.7, 95 % CI 0.81–8.8). GG homozygous genotype was detected in one healthy control and was absent from patients. The TLR4 Thr399Ileu variant was not detected in patients. Out of 200 healthy controls, 10 were heterozygous (5 %) and only one was homozygous for rare variant (0.5 %). Polymorphisms in TLR2 and TLR4 are not associated with ERA.     

Variant Toll-like receptor4 (Asp299Gly and Thr399Ile alleles) and Toll-like receptor2 (Arg753Gln and Arg677Trp alleles) in colorectal cancer

The innate immune system recognizes the presence of bacterial products through the expression of a family of membrane receptors known as Toll-like receptors (TLRs). Polymorphisms in TLRs have been shown to be associated with increased susceptibility to diseases such as inflammatory bowel disease. The aim of this study was to determine whether there was a correlation between polymorphisms of TLR4 (Asp299Gly; Thr399Ile) and TLR2 (Arg677Trp; Arg753Gln) genes and risk of colorectal cancer. DNA from 60 colorectal carcinoma patients from 3 major races in Malaysia (22 Malays, 20 Chinese and 18 Indians) and blood from 50 apparently healthy individuals were evaluated. Control group were matched to study group by race and age. The polymorphisms were determined by Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP). Genotyping results showed two out of sixty tumour specimens (3.3%) harbored both variant TLR4 Asp299Gly and Thr399Ile alleles. In contrast, DNA isolated from blood cells of 50 apparently healthy individuals harbored wild type TLR4. In the case of TLR2 Arg753Gln genotyping, all of the fifty normal and 60 tumours were of the wild type genotype. TLR2 Arg677Trp genotyping showed a heterozygous pattern in all samples. However, this may not be a true polymorphism of the TLR2 gene as it is likely due to a variation of a duplicated ( pseudogene) region. There was only a low incidence (2/60; 3.3%) of TLR4 polymorphism at the Asp299Gly and Thr399Ile alleles in colorectal cancer patients. All normal and tumour samples harbored the wild type TLR2 Arg753 allele. Our study suggests that variant TLR4 (Asp299Gly and Thr399Ile alleles) as well as TLR2 (Arg753Gln allele) are not associated with risk of colorectal cancer.     

Analysis of TLR4 and TLR2 polymorphisms in inflammatory bowel disease in a Guangxi Zhuang population

AIM: To study the polymorphisms of toll-like receptor 4 (TLR4) gene Asp299Gly, Thr399Ile and TLR2 gene Arg753Gln, Arg677Trp and susceptibility to inflammatory bowel disease (IBD) in the Zhuang population from Guangxi, China.METHODS: A case-control study was performed from February 2007 to October 2011 which included 146 Zhuang patients with IBD in the experimental group and 164 healthy Zhuang subjects who acted as the control group. All patients and healthy subjects were from the Guangxi Zhuang Autonomous Region of China. Genomic DNA was extracted from intestinal tissue by the phenol chloroform method. TLR4 gene Asp299Gly, Thr399Ile and TLR2 gene Arg753Gln, Arg677Trp were amplified by polymerase chain reaction (PCR), and then detected by PCR-restriction fragment length polymorphism (RFLP).RESULTS: The TLR4 gene Asp299Gly was digested using Nco I restriction enzyme, and a single band of 249 bp was observed which showed that it was a wild type (AA). The TLR4 gene Thr399Ile was digested using Hinf Irestriction enzyme and only the wild type (CC) was detected. In addition, the TLR2 gene Arg677Trp was digested using Aci I restriction enzyme and only the wild type (CC) was detected. The TLR2 gene Arg753Gln was digested using Pst I restriction enzyme. Only the wild type (GG) as a single band of 254 bp was observed during RFLP. Overall, no heterozygous or homozygous single nucleotide polymorphism mutations were found in patients with Crohn’s disease and ulcerative colitis both in the TLR4 gene Asp299Gly, Thr399Ile and the TLR2 gene Arg677Trp, Arg753Gln in the Zhuang population from the Guangxi Zhuang Autonomous Region of China.CONCLUSION: The TLR4 gene Asp299Gly, Thr399Ile and TLR2 gene Arg753Gln, Arg677Trp polymorphisms may not be associated with IBD in the Zhuang population from the Guangxi Zhuang Autonomous Region of China.     

Polymorphism of CD14 gene but not the mutation of TLR4 gene is associated with colorectal cancer in Chinese patients

Objectives: Toll‐like receptor 4 and CD14 are components of the lipopolysaccharide receptor complex. Our study aimed to investigate an association between TLR4 Asp299Gly and CD14‐260 polymorphisms in Chinese patients with colorectal cancer. Method: By a method of polymerase chain reaction–based restriction fragment length polymorphism (PCR‐RFLP), we genotyped TLR4 Asp299Gly and CD14‐260 polymorphisms in 110 unrelated patients with colorectal cancer and 160 healthy controls from the Chinese Han population. Results: We found significant differences in CD14 genotypes between healthy controls and patients with colorectal cancer. The frequency of the C/C genotype in healthy controls (15.6%) was significantly lower than in the group of colorectal cancer patients (32%). The frequency of the C/T genotype in healthy controls (48.1%) was significantly higher than that in the group of colorectal cancer patients (31%). No TLR4 Asp299Gly mutation was detected in any patients or healthy controls in the Chinese Han population. Conclusions: These findings indicated that the polymorphism of CD14 but not TLR4 Asp299Gly mutation was associated with Chinese patients with colorectal cancer, and the CD14 gene may contribute to the predisposition to colorectal cancer. Screening for the CD14 C‐260T genotype is likely to be a useful tool for risk assessment or prognostication for colorectal cancer in the Chinese Han population.     

Genetic polymorphism in CD14 gene,a co-receptor of TLR4 associated with non-alcoholic fatty liver disease

AIM To evaluate the pathogenic role of toll-like receptor(TLR) gene polymorphisms in patients with nonalcoholic fatty liver disease(NAFLD).METHODS Two hundred and fifty subjects(NAFLD = 200, healthy volunteers = 50) underwent polymerase chain reaction and restriction fragment length polymorphism to assess one polymorphism in the toll-like receptor 2(TLR2) gene(A753G), two polymorphisms in the TLR4 gene(TLR4 Asp299 Gly and Thr399 Ile allele), and two polymorphisms in the cluster of differentiation 14(CD14)(C-159 T and C-550T) gene, a co-receptor of TLR4. Association of TLR gene polymorphisms with NAFLD and its severity was evaluated by genetic models of association.RESULTS On both multiplicative and recessive models of gene polymorphism association, there was significant association of CD14 C(-159) T polymorphism with NAFLD; patients with TT genotype had a 2.6 fold increased risk of developing NAFLD in comparison to CC genotype. There was no association of TLR2 Arg753 Gln, TLR4 Asp299 Gly, Thr399 Ile, and CD14 C(-550) T polymorphisms with NAFLD. None of the TLR gene polymorphisms had an association with histological severity of NAFLD.CONCLUSION Patients with CD14 C(-159) T gene polymorphism, a co-receptor of TLR4, have an increased risk of NAFLD development.     

No evidence for involvement of the toll-like receptor (TLR) 4 gene Asp299Gly and Thr399Ile polymorphisms in susceptibility to primary gouty arthritis

Previous studies demonstrated that toll-like receptor (TLR) 4 was involved in the development of autoinflammatory disease including gouty arthritis (GA). TLR4 functional gene Asp299Gly and Thr399Ile polymorphisms play a role in some autoinflammatory disease susceptibility. We undertook this study to analyze the association between the genetic polymorphisms within TLR4 gene and the susceptibility to GA in Chinese Han people. Two functional variants, Asp299Gly and Thr399Ile, in the TLR4 gene were genotyped using 5′ exonuclease TaqMan^® technology from 218 male GA patients and 226 ethnically matched controls. None polymorphisms of Asp299Gly and Thr399Ile were detected in all GA cases and controls, which indicates that there is no evidence for involvement of the TLR4 gene Asp299Gly and Thr399Ile polymorphisms in susceptibility to primary GA in the Chinese Han population. Further studies with extended single nucleotide polymorphisms should be performed.     

Toll-Like Receptor 2 Gene Polymorphisms Arg677Trp and Arg753Gln in Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is a leading cause of death worldwide, with a continually rising mortality rate. As COPD is driven by abnormal pulmonary and systemic inflammation, Toll-like receptors (TLRs) seem to be important. TLRs play a key role in innate response, and in particular TLR2 gene polymorphisms Arg677Trp and Arg753Gln have been linked to an increased risk of infection. The purpose of this study was to investigate whether there is a link between polymorphisms in TLR2 and the onset or course of COPD. We analyzed 149 Caucasian COPD patients and 150 healthy individuals by using polymerase chain reaction (PCR) followed by restriction fragment length polymorphism (RFLP) analysis. To further characterize the disease, patients were classified according to GOLD and divided into two subgroups comprising a stable (60/149) course and an unstable (89/149) course. The TLR2 Arg677Trp mutant allele was not found in any of the subjects. With a prevalence of 8.72% (13/149) for TLR2 Arg753Gln, the patients did not differ from the controls, with a prevalence of 10.67% (16/150). No significant difference was apparent (P = 0.571). None of the individuals showed homozygosity for TLR2 Arg753Gln. With regard to the course of COPD, the prevalence of TLR2 Arg753Gln in the control group did not differ significantly either from the stable subgroup (P = 0.196) or from the unstable subgroup (P = 0.891). Our results suggest that there is no association of the TLR2 polymorphisms Arg677Trp and Arg753Gln with either the onset or the course of COPD.