荧光定量PCR检测尖锐湿疣皮损Toll样受体的表达水平

目的 检测尖锐湿疣皮损中Toll样受体(TLRs)的mRNA表达水平,探讨TLRs在人乳头瘤病毒(HPV)感染免疫中的可能作用.方法 提取40例尖锐湿疣患者皮损和35例HPV阴性的慢性宫颈炎患者宫颈刮落细胞的总RNA,逆转录为cDNA后用实时荧光定量PCR法检测TLR1～10的mRNA表达水平,并检测40例尖锐湿疣的HPV分型.结果 40例尖锐湿疣患者以低危型HPV6和11型为主(77.5%和55%).55%尖锐湿疣患者感染两种以上HPV亚型,其中35%合并高危型HPV感染.尖锐湿疣组TLR3、7、8的mRNA表达水平高于其他TLRs,TLR9的mRNA表达水平低于其他TLRs(P均<0.05).尖锐湿疣皮损TLR1～10的mRNA表达水平在HPV6型和HPV11型感染间以及在低危型与合并高危型HPV感染间差异无统计学意义(P均>0.05).尖锐湿疣组TLR1～3、TLR5～8和TLR10的mRNA表达水平均高于HPV阴性的慢性宫颈炎组(P均<0.05),其中TLR2、7、8的mRNA表达水平升高更显著(P均<0.01).而TLR4、TLR9的mRNA表达水平与对照组差异无统计学意义(P>0.05).结论 尖锐湿疣皮损中部分TLRs(3、7、8)表达水平较高,但TLR9表达水平较低.相对于HPV阴性的慢性宫颈炎,尖锐湿疣皮损中TLR1~3、TLR5～8和TLR10的mRNA表达上调.不同HPV型别感染的尖锐湿疣皮损中TLRs表达谱差异无统计学意义.推测尖锐湿疣TLRs表达谱的改变可能与HPV感染有一定关系,是否与HPV感染的免疫逃逸机制及持续感染有关尚有待进一步明确.

Abstract：

Objective To investigate the expression of Toll-like receptors(TLRs) in condyloma acuminatum(CA) lesions and their possible roles in the pathogenesis of CA. Methods The expressions of TLR1-10 mRNA level in the lesions of CA and in the cervix scrape cells from the patients with human papillomavirus(HPV) negative chronic cervicitis were detected by real-time quantitative fluorescent PCR. HPV typing was detected by HPV GenoArray test kit. Results Low-risk HPV type 6 and type 11 were the most prevalent types in the forty CA cases with positive rate of 77.5% and 55% respectively. 55% CA patients were found infected with more than two types of HPV. 35% CA patients were concurrently infected with high-risk HPV. The expressions of TLR3, 7, 8 mRNA were higher than other TLRs and the expression of TLR9 mRNA was lower than others in the lesions of CA. No significant differences of the TLR1-10 mRNA levels were found between HPV6 and HPV11 positive CA lesions, so did it between low-risk and high-risk HPV concurrent infected CA lesions. The expressions of TLR1-3, TLR5-8, TLR10 mRNA, especially TLR2, TLR7 and TLR8 in the lesions of CA were significantly higher than that in cervix scrape cells of HPV negative chronic cervicitis. There were no significant differences of TLR4 and TLR9 mRNA levels between the two groups. Conclusion There were higher expressions of some TLRs (3, 7, 8) and lower expression of TLR9 in the lesions of CA. Compared with HPV negative chronic cervicitis, the expressions of TLR1-3, TLR5-8, TLR10 mRNA in the lesions of CA were up-regulated. The expression profile of TLRs in different type of HPV infected CA lesions had no significant differences. Our results suggested that the expression profile of TLRs in CA may be associated with the HPV infection. Whether it was associated with the immune escape mechanism and persistent infection of HPV need further demonstration.     

Plasma cell toll‐like receptor (TLR) expression differs from that of B cells,and plasma cell TLR triggering enhances immunoglobulin production

Toll‐like receptors (TLRs) are key receptors of the innate immune system and show cell subset‐specific expression. We investigated the messenger RNA (mRNA) expression of TLR genes in human haematopoietic stem cells (HSC), in naïve B cells, in memory B cells, in plasma cells from palatine tonsils and in plasma cells from peripheral blood. HSC and plasma cells showed unrestricted expression of TLR1–TLR9, in contrast to B cells which lacked TLR3, TLR4 and TLR8 but expressed mRNA of all other TLRs. We demonstrated, for the first time, that TLR triggering of terminally differentiated plasma cells augments immunoglobulin production. Thus, boosting the immediate antibody response by plasma cells upon pathogen recognition may point to a novel role of TLRs.     

Dependence on p38 MAPK signalling in the up-regulation of TLR2, TLR4 and TLR9 gene expression in Trichomonas vaginalis-treated HeLa cells

Toll-like receptors (TLRs) are pattern recognition receptors (PRRs) that recognize conserved pathogen-associated molecular patterns (PAMPs) synthesized by micro-organisms. Despite the essential requirement for TLRs in prokaryotic infection, the pattern and regulation of TLR gene expression by Trichomonas vaginalis in the mucocutaneous barrier are still unknown. Our hypothesis is that T. vaginalis-infected epithelial cells are major effector cells in the skin barrier. These cells function as a central regulator of TLR gene expression, thus accelerating the process of barrier dysfunction via increased release of chemokines and proinflammatory cytokines. To test this hypothesis, RT-PCR was performed on TLRs, interleukin (IL)-8 and tumour necrosis factor (TNF)-alpha. Stimulation of HeLa cells by T. vaginalis was observed to up-regulate TLR2, 4 and 9 mRNA expression as well as that of IL-8 and TNF-alpha. To further clarify the molecular mechanism of barrier devastation triggered by these up-regulatory stimuli, we examined the profiles of extracellular signal-regulated kinase (ERK), p38 mitogen-activated protein kinase (MAPK) and nuclear factor (NF)-kappaB activation in HeLa cells using specific inhibitors. Interestingly, pretreatment of HeLa cells with the p38 MAPK inhibitor SB203580 demonstrated inhibition of T. vaginalis-induced up-regulation of TLR2, 4, and 9 mRNA expression. By contrast, inhibition of ERK or NF-kappaB activation failed to block T. vaginalis-induced up-regulation of TLR9 mRNA expression or TLR2 and TLR4 mRNA expression, respectively. In addition, pretreatment with SB203580 reduced epithelium-derived IL-8 and TNF-alpha release evoked by T. vaginalis. Our results show that T. vaginalis infection of the mucocutaneous barrier could up-regulate TLR2, 4 and 9 gene expression via the p38 MAPK signalling pathway in epithelial cells; this process then leads to modulation of p38 MAPK-dependent IL-8 and TNF-alpha release from the epithelium.     

Expression of Toll-like receptors and their association with cytokine responses in peripheral blood mononuclear cells of children with acute rotavirus diarrhoea

To understand virus and host interactions and host responses to rotavirus infection in children, we analysed by real-time polymerase chain reaction (PCR) the expression of mRNA for five Toll-like receptors (TLRs) (TLR2, TLR3, TLR4, TLR7 and TLR8) and four T helper (Th)1 and Th2 cytokines [interleukin (IL)-2, IL-12, interferon (IFN)-gamma and IL-4) in peripheral blood mononuclear cells (PBMC) of children with acute rotavirus diarrhoea. We observed significantly higher expression of genes encoding TLR2, TLR3, TLR4, TLR7 and TLR8 in PBMC of 41% (31/75) patients within 3 days of illness onset than those in healthy children. After 3 days of illness onset, only TLR3 and TLR8 mRNA expressions were still significantly (P<0.05) increased in 59% (44/75) children with diarrhoea. We also observed significantly (P<0.05) elevated expression of IL-12p40 and IFN-gamma in PBMC of patients during the entire period of illness and the first 3 days of illness, respectively. We further demonstrated a weak but significant association between elevated levels of gene expression of four TLRs (TLR2, TLR3, TLR4 and TLR8) and IFN-gamma. Our results suggest that multiple TLRs may modulate the immune response in the acute phase of rotavirus infection and play a role in the activation of IFN-gamma.     

Toll样受体7作为新靶点在过敏性及自身免疫性疾病中的研究进展

Toll样受体(Toll-like receptors,TLRs)属于模式识别受体(pattern recognition receptors,PRRs)家族,通过迅速识别入侵微生物病原相关分子模式(pathogen-associated molecular patterns,PAMP)激活下游信号传导途径,引发机体的免疫反应,是连接固有免疫与适应性免疫的桥梁.目前在人类发现10种不同TLRs,分别命名为TLR1 ～TLR10.近年的研究显示,TLR7与过敏性疾病、自身免疫性疾病—过敏性哮喘、系统性红斑狼疮(systemic lupus erythematosus,SLE)等有密切的联系.TLR7的激活状态影响上述疾病的发生、发展和预后.这些证据预示TLR7可能作为潜在靶点为哮喘和SLE的治疗提供新的方向.     

EV71感染患儿Toll样受体表达初探

目的 探讨肠道病毒71型( EV71)感染患儿免疫活性细胞模式识别受体(pattern recognition receptor,PRR)及细胞因子水平的变化。方法 EV71感染患儿71例,其中轻症EV71感染组20例,重症EV71感染组25例,危重症EV71感染组26例,同年龄正常对照组20例。采用real -time PCR检测外周血单个核细胞维甲酸蛋白Ⅰ(retinoic acidinducible gene Ⅰ,RIG-Ⅰ)、黑色素瘤分化相关基因5（melanoma differentitation-associated gene 5,MDA5）及细胞因子(IL-12、IFN-α)表达;流式细胞术检测外周血单核/巨噬细胞( monocyte/macrophages,MC)、髓样树突状细胞(myloid dentritic cells,mDC)及浆样树突状细胞（plasmacytoid dentritic cells,pDC）Toll样受体(TLRs)表达率;ELISA检测细胞因子IL-12及IFN-α的变化。结果 (1)轻症患儿仅TLR7升高,重症EV71感染患儿外周血MC、mDC、pDCTLR7表达明显升高(P＜0.05),MC、mDC高表达TLR2、3、4,危重症患儿呈下降趋势。(2)EV71感染患儿胞内模式识别受体RIG- Ⅰ/MDA5 mRNA表达明显增加;(3)轻症患儿DC相关细胞因子有上升趋势,重症患儿DC相关细胞因子IL-12、IFN-α明显增高(P＜0.05),轻症及危重症患儿明显降低(P＜0.05)。结论 TLR7可能是免疫活性细胞识别EV71的主要模式识别受体;RIG-I/MDA5也可能参与识别EV71;合并细菌感染或细胞破坏释放的内源性配体导致TLR2或TLR4活化,诱导炎症反应。     

IFNs activate toll-like receptor gene expression in viral infections

Toll-like receptors (TLRs) mediate innate immune responses to microbes. TLR2, TLR5, TLR6, and TLR9 have been implicated in responses to bacterial components, and TLR4 is the receptor for Gram-negative bacteria. Recently, TLR4 was described to function in respiratory syncytial virus-induced NF-kappaB activation. Here we have analyzed TLR1-9 mRNA expression in human primary macrophages infected with influenza A and Sendai viruses. TLR1, TLR2, TLR4, TLR6, and TLR8 mRNAs were expressed at basal levels in macrophages. Viral infection enhanced TLR1, TLR2, TLR3, and TLR7 mRNA expression, and neutralizing anti-IFN-alpha/beta antibodies downregulated gene expression of these TLRs. Exogenously added IFN-alpha upregulated TLR1, TLR2, TLR3, and TLR7 mRNA expression in macrophages, as well as TLR3 mRNA expression in epithelial and endothelial cell lines. IFN-gamma enhanced the expression of TLR1 and TLR2 mRNA in macrophages, and TLR3 in epithelial and endothelial cells. The data suggests a novel role for IFNs in the activation of innate immunity.     

Porcine Toll-like receptors: the front line of pathogen monitoring and possible implications for disease resistance

Toll-like receptors (TLRs) are the most famous pattern-recognition receptors (PRRs); they monitor pathogen-associated molecular patterns and play a critical role in activation of the immune system against infection. TLR gene mutations may affect the gene products in terms of their ligand-binding ability or their signal transduction ability after ligand binding; such changes have a great influence on pathogen monitoring and disease resistance. Thirteen mammalian TLRs have been identified, and genes corresponding to all 10 TLR genes identified in humans have been fully cloned in pigs. Porcine TLR gene coding sequences possess a large number of nonsynonymous single nucleotide polymorphisms (SNPs). They are concentrated in ectodomains, and may increase the variability of pathogen recognition in pig populations. We summarize the current knowledge of TLR molecules in mammals and livestock (particularly pigs) and speculate on the relationship between SNPs in porcine TLRs and their application to vaccine design and disease-resistance breeding.     

Triggering of toll-like receptor signaling pathways in T cells contributes to the anti-tumor efficacy of T cell responses

Traditionally, expression of toll-like receptors (TLRs) has been associated with innate immune cells in particular professional antigen presenting cells and natural killer cells. This led to the concept that the adjuvant effects of ligation of TLR in a host occur mainly in innate immune cells. However, this concept has been challenged by recent studies including ours demonstrating that T cells express appreciated levels of different TLRs, which can serve as costimulatory co-receptors during polyclonal and antigen-specific stimulation of T cells. Because T cells express low levels of TLRs as compared to innate immune cells, increasing the expression levels of TLRs in T cells can significantly maximize their responses to the costimulatory effects of TLR ligation. This review article focuses on the potential role of TLR expression in T cells in their responses to vaccination regimen containing TLR agonists and how it can be modulated to optimize anti-tumor immunity.     

Expression and distribution of Toll-like receptors 11–13 in the brain during murine neurocysticercosis

The functions of Toll-like receptors (TLRs) 11–13 in central nervous system (CNS) infections are currently unknown. Using a murine model of neurocysticercosis, we investigated the expression and distribution of TLRs 11–13 by using both gene specific real-time PCR analysis and in situ immunofluoresence microscopy in both control and neurocysticercosis brains. In the mock infected brain, mRNAs of TLRs 11–13 were constitutively expressed. Parasite infection caused an increase of both mRNAs and protein levels of all three TLRs by several fold. All three TLR proteins were present in both CNS and immune cell types. Among them TLR13 was expressed the most in terms of number of positive cells and brain areas expressing it, followed by TLR11 and TLR12 respectively. Among the nervous tissue cells, TLRs 11–13 protein levels appeared highest in neurons. However, TLR13 expression was also present in ependymal cells, endothelial cells of pial blood vessels, and astrocytes. In contrast, infiltrating CD11b and CD11c positive myeloid cells predominantly produced TLR11 protein, particularly early during infection at 1 wk post infection (~50% cells). TLRs 12 and 13 proteins were present on approximately 5% of infiltrating immune cells. The infiltrating cells positive for TLRs 11–13 were mostly of myeloid origin, CD11b+ cells. This report provides a comprehensive analysis of the expression of TLRs 11–13 in normal and parasite infected mouse brains and suggests a role for them in CNS infections.     

Rotavirus and coxsackievirus infection activated different profiles of toll-like receptors and chemokines in intestinal epithelial cells

Objective  To understand the inflammatory-immune response in intestinal epithelial cells after infection of rotavirus and coxsackievirus B3. Methods  We examined by quantitative PCR the expression profiles of genes encoding five toll-like receptors (TLR) and levels of three chemokines in response to rotavirus and coxsackievirus B3 infection in a human intestinal epithelial cell line (HT-29 cells). Results  We demonstrated that rotavirus induced significantly increased levels of mRNA expression for TLR2, TLR3, TLR7 and TLR8 in HT-29 cells in a time-dependent manner. In contrast, coxsackievirus B3 did not stimulate mRNA expression for TLR3. Rotavirus and coxsackievirus B3 also induced higher levels of mRNA expression for RANTES, IP-10 and IL-8 during the period of infection in a different manner. Finally, significantly elevated levels of RANTES, IP-10 and IL-8 were detected by ELISA in rotavirus-infected cells from 24 to 48 h. Conclusion  Our findings suggest that different patterns of TLRs and chemokines were induced in the initiation and modulation of immune response to rotavirus and coxsackievirus B3 infection.     

Allelic variation of the ovine Toll-like receptor 4 gene

The family of Toll-like receptors (TLRs) is responsible for recognition of pathogen-associated molecular patterns (PAMPs), and Toll-like receptor 4 (TLR4) recognizes not only exogenous ligands such as the lipopolysaccharide (LPS) of Gram-negative bacteria, but also a number of endogenous ligands. Variation in the nucleotide sequence of the ovine TLR4 gene was investigated by amplification of a fragment containing a putative ligand-binding region using polymerase chain reaction (PCR), followed by single-strand conformational polymorphism (PCR-SSCP) analysis and DNA sequencing. Four novel SSCP patterns, representing four different sequences, were identified. Either one or two different sequences were detected in individual sheep and all the sequences identified shared high homology to the TLR4 sequences from a variety of species, suggesting that these sequences represent allelic variants of the ovine TLR4 gene. Fourteen single nucleotide polymorphisms (SNPs) were detected, and 79% (11 of 14) of SNPs were non-synonymous substitutions that would result in amino acid changes. Variation detected here might have an impact on pattern recognition and hence affect the immune response to pathogens.     

Regulation and signal transduction of toll-like receptors in human chorioncarcinoma cell lines

PROBLEM: Toll-like receptors (TLRs) are expressed on placental cells. The aim of this study is to analyze signaling components activated in placenta cells after TLR ligand engagement. METHODS OF STUDY: In chorioncarcimoma cell lines the regulation of TLRs was determined by real time polymerase chain reaction as well as by fluorescence-activated cell sorter analysis. Activation of NF-kappaB was determined in a reporter assay system and the activation of the mitogen-activated protein kinase signaling pathways by immunoblot analysis. RESULTS: Both lipopolysaccharide (LPS) and DNA oligonucleotides containing unmethylated CpG motifs (CpG) induced the enhanced expression of TLR2 mRNA as well as a TLR2 surface protein expression. Functionally, incubation of JAR cells with microbial stimuli such as LPS activated NF-kappaB, as well as the phosphorylation of ERK1/2 and p38 MAP kinases and secretion of interleukin-8. CONCLUSION: The functional expression of TLRs on placental cells may play an important role in the initiation of an immune response in the developing fetus.     

Toll-like receptors (TLRs) in innate immune defense against Staphylococcus aureus

Toll-like receptors (TLRs) are the most important class of innate pattern recognition receptors (PRRs) by which host immune and non-immune cells are able to recognize pathogen-associated molecular patterns (PAMPs). Most mammalian species have 10 to 15 types of TLRs. TLRs are believed to function as homo- or hetero-dimers. TLR2, which plays a crucial role in recognizing PAMPs from Staphylococcus aureus, forms heterodimers with TLR1 or TLR6 and each dimer has a different ligand specificity. Staphylococcal lipoproteins, Panton-Valentine toxin and Phenol Soluble Modulins have been identified as potent TLR2 ligands. Conversely, the ligand function attributed to peptidoglycan and LTA remains controversial. TLR2 uses a MyD88-dependent signaling pathway that results in NF-kB translocation into the nucleus and activation of the expression of pro-inflammatory cytokine genes. Recognition rouses both an inflammatory response, culminating in the phagocytosis of bacteria, and an adaptive immune response, with the presentation of resulting bacterial compounds to T cells. Here, recent advances on the recognition of S. aureus by TLRs are presented and discussed, as well as the new therapeutic opportunities deriving from this new knowledge.     

脐血与成人外周血粒细胞Toll样受体表达的比较

 目的：比较脐血与成人外周血粒细胞Toll样受体（TLRs）的表达情况,为新生儿相关疾病的临床治疗积累实验资料。方法：取脐血和成人外周血,用密度梯度离心结合红细胞裂解法分离、收集粒细胞,流式细胞术鉴定粒细胞纯度,RT-qPCR检测TLRs 10个成员的mRNA表达水平,流式细胞术测定部分TLRs的蛋白荧光强度。结果：（1）流式细胞术检测结果：采用密度梯度离心结合红细胞裂解法分离收集的脐血粒细胞CD19-CD24+为（95.66±1.73）%,CD3+为（4.27±1.22）%,成人外周血粒细胞CD19-CD24+为（95.48±2.13）%,CD3+为（4.82±1.07）%。（2）RT-qPCR结果显示：脐血粒细胞和成人外周血粒细胞TLR1（0.141±0.091 vs 0.691±0.447）、TLR2（0.388±0.337 vs 0.901±0.508）、TLR4(0.093±0.071 vs 0.254±0.147)、TLR6(0.056±0.045 vs 0.202±0.034)、TLR7(0.001±0.001 vs 0.004±0.003)和TLR8(0.046±0.040 vs 0.211±0.146）的表达差异有统计学意义（P<0.01）,TLR3、TLR5、TLR9和TLR10的表达差异无统计学意义(P>0.05);其中TLR3、TLR7和TLR9在脐血和成人外周血粒细胞的相对表达水平均较低。（3）流式分析显示脐血与成人外周血粒细胞TLR2平均蛋白荧光强度（21.40±3.09 vs 30.50±5.69）差异有统计学意义（P<0.05）;而TLR4平均蛋白荧光强度差异无统计学意义（P>0.05）。结论：脐血粒细胞TLR1、TLR2、TLR4和TLR6 mRNA及TLR2蛋白表达低于成人外周血粒细胞,提示新生儿粒细胞识别细菌性病原微生物感染的能力可能存在缺陷或尚未完全成熟。这是否与新生儿急性细菌性毒血症发病及病死率较高有直接联系,有待进一步研究。