TLR4 Single Nucleotide Polymorphisms Research Articles

MYD88 and functionally related genes are associated with multiple infections in a model population of Kenyan village dogs.

The purpose of this study was to seek associations between immunity-related molecular markers and endemic infections in a model population of African village dogs from Northern Kenya with no veterinary care and no selective breeding. A population of village dogs from Northern Kenya composed of three sub-populations from three different areas (84, 50 and 55 dogs) was studied. Canine distemper virus (CDV), Hepatozoon canis, Microfilariae (Acantocheilonema dracunculoides, Acantocheilonema reconditum) and Neospora caninum were the pathogens studied. The presence of antibodies (CDV, Neospora), light microscopy (Hepatozoon) and diagnostic PCR (Microfilariae) were the methods used for diagnosing infection. Genes involved in innate immune mechanisms, NOS3, IL6, TLR1, TLR2, TLR4, TLR7, TLR9, LY96, MYD88, and three major histocompatibility genes class II genes were selected as candidates. Single nucleotide polymorphism (SNP) markers were detected by Sanger sequencing, next generation sequencing and PCR-RFLP. The Fisher´s exact test for additive and non-additive models was used for association analyses. Three SNPs within the MYD88 gene and one TLR4 SNP marker were associated with more than one infection. Combined genotypes and further markers identified by next generation sequencing confirmed associations observed for individual genes. The genes associated with infection and their combinations in specific genotypes match well our knowledge on their biological role and on the role of the relevant biological pathways, respectively. Associations with multiple infections observed between the MYD88 and TLR4 genes suggest their involvement in the mechanisms of anti-infectious defenses in dogs.

A case-control study of innate immunity pathway gene polymorphisms in Puerto Ricans reveals association of toll-like receptor 2 +596 variant with asthma.

BackgroundFor many years, African Dust Storms (ADE) has been thought to be associated with high prevalence of asthma in Puerto Rico (PR). Endotoxins (ENX) have been associated with ADE particulate matter (PM) and are known to promote pro-inflammatory responses in lung cells of susceptible individuals through the Toll-like receptor (TLR2/4) signaling pathways. Genetic variants are plausible contributors to such susceptibility. Therefore, we have evaluated a series of nine single nucleotide polymorphisms (SNPs) in TLR genes, which have been correlated positive and negatively to asthma prevalence and/or risk, in the Puerto Rican asthmatic population.MethodsThe following SNPs were evaluated in 62 asthmatics and 61 controls through Taqman® Real Time PCR Assay: TLR4 (+896A/G, +1196C/T, −6687A/G); TLR2 (+596C/T, −16934 T/A, +399A/G, +1349C/T) and CD14 (−159C/T, +1188C/G). Genotypes were assessed for asthma association employing an odds ratio (OR) analysis.ResultsMinor allele frequencies (n = 123) were determined for those variants as 0.07, 0.06, 0.35, 0.35, 0.37, 0.29, 0.04, 0.35 and 0.11, respectively. Two (+596C/T, +399A/G) TLR2 SNPs showed to be more represented in the asthmatic group by 89 % and 65 %, respectively. TLR4 SNP +896A/G analysis revealed only 1 G/G genotype (2 %) on the asthmatic group. The CD14 SNPs were similarly represented in the Puerto Rican population. Only the TLR2 +596 SNP was found to be significantly associated to asthma (OR = 3.24 for CT, 2.71 for TT) and particularly to females.ConclusionsThe identification of TLR SNPs will reveal potential candidates for gene-environment interactions in Puerto Ricans. As far as we know this is the first study to evaluate this type of TLR gene polymorphisms in Puerto Rican asthmatics, contributing to the current knowledge in the Hispanic population.Electronic supplementary materialThe online version of this article (doi:10.1186/s12890-016-0272-7) contains supplementary material, which is available to authorized users.

Genetic polymorphisms in the CD14 gene are associated with monocyte activation and carotid intima-media thickness in HIV-infected patients on antiretroviral therapy.

HIV-infected individuals on antiretroviral therapy (ART) are at increased risk of cardiovascular disease (CVD). Given the relationship between innate immune activation and CVD, we investigated the association of single-nucleotide polymorphisms (SNPs) in TLR4 and CD14 and carotid intima-media thickness (cIMT), a surrogate measurement for CVD, in HIV-infected individuals on ART and HIV-uninfected controls as a cross-sectional, case-control study. We quantified the frequency of monocyte subsets (CD14, CD16), markers of monocyte activation (CD38, HLA-DR), and endothelial adhesion (CCR2, CX3CR1, CD11b) by flow cytometry. Plasma levels of lipopolysaccharide, sCD163, sCD14, sCX3CL1, and sCCL2, were measured by ELISA. Genotyping of TLR4 and CD14 SNPs was also performed. The TT genotype for CD14/-260SNP but not the CC/CT genotype was associated with elevated plasma sCD14, and increased frequency of CD11b+CD14+ monocytes in HIV-infected individuals. The TT genotype was associated with lower cIMT in HIV-infected patients (n = 47) but not in HIV-uninfected controls (n = 37). The AG genotype for TLR4/+896 was associated with increased CX3CR1 expression on total monocytes among HIV-infected individuals and increased sCCL2 and fibrinogen levels in HIV-uninfected controls. SNPs in CD14/-260 and TLR4/+896 were significantly associated with different markers of systemic and monocyte activation and cIMT that differed between HIV-infected participants on ART and HIV-uninfected controls. Further investigation on the relationship of these SNPs with a clinical endpoint of CVD is warranted in HIV-infected patients on ART.

Risk Factors for Hepatocellular Carcinoma in Cirrhotic Patients with Chronic Hepatitis B.

To investigate the clinical and genetic risk factors associated with hepatocellular carcinoma (HCC) in cirrhotic patients with chronic hepatitis B (CHB). Nine hundred forty-nine Chinese Han patients with CHB were studied, including noncirrhotic patients without HCC (N = 234), cirrhotic patients without (N = 281) and with HCC (N = 434). Patients were genotyped for 10 candidate single nucleotide polymorphisms (SNPs) by the polymerase chain reaction (PCR)-ligase detection reaction (LDR) method. By multivariate logistic regression analysis adjusted for Child-Pugh scores, noneffective antiviral treatment, drinking history, family history of HCC, and age ≥50 years old were associated with HCC risk (odds ratio [OR] = 5.923, 2.456, 2.241, 1.955, respectively). Sixty-two of 170 cirrhotic patients who achieved sustained virological suppression by antiviral treatment developed HCC, with fatty liver disease, family history of HCC, and family history of hepatitis B virus (HBV) infection as the risk factors (OR = 11.646, 3.339, 2.537, respectively). The SNPs associated with HCC risk in patients with cirrhosis and CHB were rs11536889 in TLR4 and rs2853744 in SPP1. Polymorphisms of TLR4 rs2149356, AP3S2 rs2290351, STXBP5L rs2169302, MLEC rs7976497, and SOCS3 rs4969168 were associated with HCC risk in specific stratified analyses with gender, age, and drinking history in the cirrhotic patients. Inadequate antiviral treatment, family history of HCC, drinking history, and age ≥50 years old are risk factors for HCC. Sustained suppression of HBV does not eliminate the risk of HCC. Specific host genetic factors may impact HCC development in Han Chinese cirrhotic patients with CHB, including SNPs in TLR4, SPP1, AP3S2, STXBP5L, MLEC, and SOCS3, which warrant further validation in additional cohorts.

Clinical Significance of TLR1 I602S Polymorphism for Patients with Metastatic Colorectal Cancer Treated with FOLFIRI plus Bevacizumab.

The purpose of this study was to evaluate the clinical significance of single-nucleotide polymorphisms in TLR1, TLR2, TLR6, and TAK1 in patients with metastatic colorectal cancer (mCRC). We genotyped 9 SNPs of TLR1, TLR2, TLR6, and TAK1 in mCRC patients treated with first-line FOLFIRI (combination therapy of irinotecan, 5-fluorouracil, and folinic acid) plus bevacizumab, using a discovery cohort (TRIBE trial, n = 228) and a validation cohort (FIRE-3 trial, n = 297), and analyzed for the association with response rate (RR), progression-free survival (PFS), and overall survival (OS). There was a significant association of TLR1 rs5743618 (T1805G) with the clinical outcome. In the TRIBE cohort, a homozygous wild-type genotype (T/T) associated with a significantly lower RR compared with variant T/G and G/G genotypes (43% vs. 62%, P = 0.025), and this observation was validated in the FIRE-3 cohort (46% vs. 65%, P = 0.021). In addition, those patients with the T/T genotype had significantly worse PFS (median, 8.2 vs. 10.5 months; HR, 1.57; 95% CI, 1.09-2.28, P = 0.014) and OS (median: 19.9 vs. 27.9 months; HR, 1.63; 95% CI, 1.14-2.35, P = 0.007), compared with those with other genotypes in the TRIBE cohort. These differences remained statistically significant in multivariate analysis. Our data suggest that TLR1 rs5743618 could serve as a predictor of clinical response to FOLFIRI plus bevacizumab in patients with mCRC. Mol Cancer Ther; 15(7); 1740-5. ©2016 AACR.

Common NOD2/CARD15 and TLR4 Polymorphisms Are Associated with Crohn's Disease Phenotypes in Southeastern Brazilians.

To investigate whether variants in NOD2/CARD15 and TLR4 are associated with CD and ulcerative colitis (UC) in a genetically admixed population of Rio de Janeiro, where IBD has continued to rise. We recruited 67 consecutive patients with CD, 61 patients with UC, and 86healthy and ethnically matched individuals as controls. DNA was extracted from buccal brush samples and genotyped by PCR with restriction enzymes for G908R and L1007finsC NOD2/CARD15 single-nucleotide polymorphisms (SNPs) and for T399I and D299G TLR4 SNPs. Clinical data were registered for subsequent analysis with multivariate models. NOD2/CARD15 G908R and L1007finsC SNPs were found in one and three patients, respectively, with CD. NOD2/CARD15 G908R and L1007finsC SNPs were not found in any patients with UC, but were found in three and three controls, respectively. With regard to the TLR4 gene, no significant difference was detected among the groups. Overall, none of the SNPs investigated determined a differential risk for a specific diagnosis. Genotype-phenotype associations were found in only CD, where L1007finsC was associated with colonic localization; however, TLR4 T399I SNP was associated with male gender, and D299G SNP was associated with colonic involvement, chronic corticosteroid use, and the need for anti-TNF-alpha therapy. Variants of NOD2/CARD15 and TLR4 do not confer susceptibility to IBD, but appear to determine CD phenotypes in this southeastern Brazilian population.

Sex-specific effects of TLR9 promoter variants on spontaneous clearance of HCV infection

ObjectiveAs pathogen sensors, Toll-like receptors (TLR) play a role in the first defence line during HCV infection. However, the impact of the DNA sensor TLR9 on the natural course of...

Altered Th17 Cytokine Expression in Helicobacter pylori Patients with TLR4 (D299G) Polymorphism

ABSTRACTHelicobacter pylori (H. pylori) is associated with gastric ulcer and gastric adenocarcinoma. Polymorphisms in the host genes coding for Toll-like receptors (TLRs) may influence the innate and adaptive immune response to the infection, affecting the susceptibility to H. pylori or the disease outcomes. However, the details and association with different polymorphism and clinical expression of infection remain unclear. A case-control study consisting of 58 patients with H. pylori infection and 44 H. pylori uninfection was conducted. Genomic DNA was extracted and genotypes of TLR4 Asp299Gly polymorphism were assessed through polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Mucosal cytokines expression in H. pylori-infected and uninfected gastric biopsies was determined by real-time PCR. The expression of IL-6, IL-17, IL-21, IL-23 and TGF-β1 was significantly higher in patients with D299G polymorphism in TLR4. But the expression of IL-18 between patients with single-nucleotide polymorphisms (SNPs) in TLR4 and patients with the wild-type allele was not significant. In H. pylori-infected patients with gastritis, SNPs in TLR4 may alter cytokine expression toward Th17 immune response in the gastric mucosa and may have increased risk for the development of peptic ulcer.

A common TLR1 polymorphism is associated with higher parasitaemia in a Southeast Asian population with Plasmodium falciparum malaria.

Background The factors leading to poor outcomes in malaria infection are incompletely understood. Common genetic variation exists in the human genes for Toll like receptors (TLRs) that alter host responses to pathogen-associated molecular patterns. Genetic variation in TLR1 and TLR6 could alter the risk of development of complicated malaria and ability of the host to control the parasite burden during acute Plasmodium falciparum infection.Methods Five single nucleotide polymorphisms in TLR1 and TLR6 in 432 patients with clinical P. falciparum monoinfection acquired on the Thai-Myanmar border were genotyped. Using logistic regression, associations with the development of complicated malaria and the percentage of infected erythrocytes (parasitaemia) on the day of presentation to clinical care (day zero) were tested.ResultsGenotypes carrying the T (major) allele of TLR1 rs5743551—an allele associated with improved outcomes in sepsis—were associated with higher parasitaemia measured on day zero (p = 0.03).DiscussionSince malaria exerts strong genetic pressure on the human genome, protection from parasitaemia associated with TLR1 rs5743551 may account for the maintenance of an allele associated with poor outcomes in Caucasians with sepsis.ConclusionThese data suggest that genetic variation in TLR1 has effects on the host response to Plasmodium falciparum malaria in Asian populations. Genotypes from TLR6 showed no evidence of association with either complicated malaria or parasite burden.

Frequency of TLR4 (1063A/G and 1363C/T) polymorphisms in healthy and HIV-infected Omani individuals and their relationship to viral load and T cell count.

Toll-like receptors (TLRs) are essential elements of the innate immune response to different infections including the infection with human immunodeficiency virus (HIV). Single nucleotide polymorphisms (SNPs) in TLRs such as TLR4 1063A/G and 1363C/T have been found to be associated with changes in CD4 count, viral load (VL), and disease progression during HIV infection. However, the association of these SNPs with the pathogenesis during HIV infection is controversial. We investigated the frequency of TLR4 1063A/G and 1363C/T SNPs in 168 Omani donors [68 HIV-infected patients (>3% of Omani HIV-infected patients) and 100 healthy controls] and the association of these SNPs with the VL, CD8 and CD4 counts, and the immune recovery after cART as observed by CD4 T cell increase. SNPs were analyzed after the amplification of the regions that contain them by polymerase chain reaction (PCR) and sequencing of the PCR products. The TLR4 1063GG genotype was detected in the HIV-infected group only. No association was found between the studied SNPs and the average VL during 1 year of infection, the average CD4 and CD8 count during 1 year of viremia, the nadir CD4 count, the CD4 count when the patient reached VL < 50 copies/mL due to cART, and the ratio of the CD4 count 3 and 6 months after reaching VL < 50 copies/mL after cART to the last CD4 count before reaching VL < 50 copies/mL. Our study suggests that TLR4 (1063A/G and 1363C/T) SNPs have no association with the VL or the CD4 and CD8 counts during HIV infection.

TLR2, TLR4 and TLR9 genotypes and haplotypes in the susceptibility to and clinical course of Chlamydia trachomatis infections in Dutch women.

Chlamydia trachomatis infections demonstrate remarkable differences in clinical course that are approximately 40% based on host genetic variation. Here, we study the single nucleotide polymorphisms (SNPs) and their haplotypes in TLR2, TLR4 and TLR9 (TLR2 +2477G>A; TLR2 -16934T>A; TLR4+896A>G; TLR9 -1237T>C and TLR9 +2848G>A) in relation to the susceptibility to, and severity of C. trachomatis infections. We analysed the five SNPs in a cohort of 770 Dutch Caucasian women either attending a sexually transmitted diseases outpatient clinic (n = 731) or having complaints of subfertility (n = 39). Haplotype analyses showed a trend for TLR2 haplotype I (-16934T/+2477G) to protect against the development of symptoms and tubal pathology (Ptrend = 0.03) after Chlamydia infection. In the susceptibility cohort, TLR9 haplotype III (-1237C/+2848A) showed a significant decreasing trend in the development of symptoms after C. trachomatis infection (P = 0.02, OR: 0.55, 95%CI: 0.33-0.91). Logistic regression of the TLR2 haplotypes, TLR4+896A>G, and TLR9 haplotypes showed that the TLR2 haplotype combinations AG-TA and AG-TG confer risk (OR 3.4 (P = 0.01) and 1.6 (P = 0.03)), while the TLR9 haplotype combination TG-TA protects against C. trachomatis infections (OR: 0.4, P = 0.004). Our study shows that both TLR2 and TLR9 genes and SNP combinations do influence the clinical course of Chlamydia infections.

Polymorphisms at Locus 4p14 of Toll-Like Receptors TLR-1 and TLR-10 Confer Susceptibility to Gastric Carcinoma in Helicobacter pylori Infection.

Helicobacter pylori (H. pylori) -induced gastric inflammation impacts the functions of leptin- and ghrelin-producing cells in the gastroduodenum. Inflammation resulting from H. pylori sensing via Toll-like receptors (TLRs) and the associated downstream signaling largely remain ambiguous. Here, we investigated the role of gut hormones, pro-inflammatory cytokines and single nucleotide polymorphisms (SNPs) associated with TLR 4p14 in H. pylori disease in 30 subjects with non-ulcer dyspepsia (NUD), 40 with peptic ulcer disease (PUD) and 15 with gastric cancer (GC) subjects positive and negative for H. pylori infection. The level of pro-inflammatory cytokines was directly proportional to the severity of gastritis, and disease status influenced the levels of gut hormones and pro-inflammatory cytokines. TLR-1 SNPs rs4833095 and TLR-10 SNPs rs10004195 and were directly associated with H. pylori disease, and were up-regulated in the presence of H. pylori in a genotype-independent manner. We concluded that TLR-1 rs4833095 and TLR10 rs10004195 confer susceptibility to development of gastroduodenal disease, especially GC in H.pylori disease.

TLR4 Asp299Gly polymorphism may be protective against chronic periodontitis.

Periodontitis results from interplay between genetic and environmental factors. Single nucleotide polymorphisms (SNPs) in the coding region of the toll-like receptor 4 gene (TLR4) may be associated with periodontitis, although previous studies have been inconclusive. Moreover, the interaction between environmental factors, such as cigarette smoking (a major risk factor for periodontitis), and Porphyromonas gingivalis (a major periodontal pathogen) with the TLR4 coding region Asp299Gly SNP (rs4986790; a SNP associated with lipopolysaccharide-mediated inflammatory responses in periodontitis), have been largely ignored in previous reports. Therefore, the objective of this study was to examine the association between TLR4 Asp299Gly (rs4986790) with alveolar bone height loss (ABHL) and periodontitis, accounting for interactions between this SNP with smoking and P.gingivalis prevalence. The CD14/-260 SNP (rs2569190) served as a control, as a recent meta-analysis suggested no relationship between this SNP and periodontitis. This multicenter study included 617 participants who had rheumatoid arthritis or osteoarthritis. This report presents a secondary outcome from the primary case-control study examining the relationship of periodontitis with established rheumatoid arthritis. The Centers for Disease Control/American Academy of Periodontology case definitions of periodontitis were used for this analysis. Participants received a full-mouth clinical periodontal examination and panoramic radiograph. Percentage ABHL was measured on posterior teeth. The TLR4 Asp299Gly and CD14/-260 SNPs were selected a priori and genotypes were determined using the ImmunoChip array (Illumina(®) ). Minor allele frequencies and associations with periodontitis and ABHL did not differ according to rheumatoid arthritis vs. osteoarthritis status; therefore, data from these two groups were pooled. The presence of P.gingivalis was detected in subgingival plaque by PCR. Multivariate ordinal logistic regression examined associations between the SNPs and periodontitis or ABHL. SNP interactions with smoking and P.gingivalis were analyzed. A significant, negative interaction was observed between the TLR4 SNP and the presence of P.gingivalis (p=0.045) with respect to periodontitis. The TLR4 minor variant was also associated with less ABHL: 16.8% of individuals with low ABHL, 9.0% with moderate ABHL and 11.2% with high ABHL had the minor allele [p=0.029; odds ratio=0.58 (95% confidence interval: 0.36-0.95)]. The interaction between the TLR4 SNP and smoking was not significant with respect to periodontitis or ABHL. The CD14 SNP was not associated with periodontitis or ABHL. The TLR4 Asp299Gly SNP significantly interacted with P.gingivalis in conferring a decreased risk of periodontitis and may be protective against ABHL, a feature of periodontitis. Agents blocking TLR4 signaling, a strategy currently under investigation for the treatment of other inflammatory conditions, may warrant investigation in the context of periodontitis related to the presence of P.gingivalis.

Polymorphisms in TLR9 but not in TLR5 increase the risk for duodenal ulcer and alter cytokine expression in the gastric mucosa.

Colonization of the gastric mucosa by Helicobacter pylori can lead to peptic ulcer and gastric adenocarcinoma. TLRs are signaling receptors involved in the recognition of microorganisms, and polymorphisms in their genes may influence the innate and adaptive immune response to H. pylori, affecting the clinical outcomes of the infection. We assessed the association between single nucleotide polymorphisms in TLR9 and TLR5 and gastroduodenal diseases. All patients were genotyped by allelic discrimination in regions 1174C>T and 1775A>G of TLR5 and -1237T>C and 2848G>A of TLR9. The 2848A allele of TLR9 was more frequent in duodenal ulcer and showed an association of risk with this pathology. Polymorphisms in TLR5 were not found to be associated with disease. Patients with polymorphisms in TLR9 and TLR5 expressed significantly lower levels of IL-1β and TNF-α, whereas polymorphisms in TLR5 also decreased the expression of IL-6 and IL-10. Our findings suggest that 2848G>A polymorphism in TLR9 increases the risk for the development of duodenal ulcer probably by modifying the inflammatory response to H. pylori infection. This is the first study to show an association of 2848A allele of TLR9 with duodenal ulcer and with altered expression of inflammatory cytokines in the gastric mucosa.

Single nucleotide polymorphism of toll-like receptor 4 (TLR4) is associated with juvenile spondyloarthritis in Croatian population.

Single nucleotide polymorphisms (SNP) of toll-like and NOD-like receptors have been associated with altered receptor activity and modified production of proinflammatory cytokines leading to a number of diseases. Our aim was to determine whether SNP of TLR2 (Arg753Gln), TLR4 (Asp299Gly, Thr399Ile), and NLRP3 (Q705K) influence susceptibility to juvenile spondyloarthrtis (jSpA) and juvenile idiopathic arthritis (JIA). After the DNA extraction, 26 patients with jSpA, 11 with oligoarticular, polyarticular, or systemic JIA, and 40 healthy controls were genotyped for Arg753Gln, Asp299Gly, Thr399Ile, and Q705K SNP using real-time PCR-SNP analysis. Statistically significant difference in genotype frequency for Thr399Ile SNP of TLR4 was observed in the jSpA (χ2 = 6.705, p = 0.035) and not in the JIA group (χ2 = 3005, p = 0.223). Regarding Asp299Gly SNP, no significant difference in genotype frequency was found; however, allele frequency was significant in both jSpA and JIA patients. No significant difference in genotype or allele frequency was observed for Arg735Gln and Q705K SNP. The399Ile polymorphism of TLR4 may be responsible for altered immune response to microbial infection in variant carriers and represent a mechanism of triggering overproduction of proinflammatory cytokines and long-term inflammation in jSpA. SNP of TLR2, NLRP3, and TLR4 (Asp299Gly) were not associated with jSpA or JIA.

TLR9 2848 GA heterozygotic status possibly predisposes fetuses and newborns to congenital infection with human cytomegalovirus.

BackgroundSome single nucleotide polymorphisms (SNP), located in Toll-like receptor (TLR) genes, were reported to be associated with human cytomegalovirus (HCMV) infections. The study was aimed to assess the correlation of SNPs at TLR4 and TLR9 genes with the occurrence of congenital cytomegaly, based on available samples.MethodsReported case-control study included both HCMV infected and non-infected fetuses and newborns. The specimens were classified to the molecular analyses, based on serological features of the recent infection and HCMV DNAemia in body fluids. TLR SNPs were studied, using multiplex nested PCR-RFLP assay, and determined genotypes were confirmed by sequencing. Hardy-Weinberg equilibrium was assessed for the identified genotypes. The linkage disequilibrium was also estimated for TLR4 SNPs. A relationship between the status of TLR genotypes and congenital cytomegaly development was estimated, using a logistic regression model.ResultsHardy Weinberg equilibrium was observed for almost all SNPs, both infected and non-infected patients, with exception of TLR4 896 A>G polymorphism in the control group (P≤0.050). TLR4 896 A>G and 1196 C>T SNPs were found in linkage disequilibrium in both study groups (P≤0.050). The CC genotype at TLR4 1196 SNP and the GA variant at TLR9 2848 G>A SNP were significantly associated with HCMV infection (P≤0.050). The risk of congenital cytomegaly was higher in heterozygotes at TLR9 SNP than in the carriers of other genotypic variants at the reported locus (OR 4.81; P≤0.050). The GC haplotype at TLR4 SNPs and GCA variants at TLR4 and TLR9 SNPs were significantly associated with HCMV infection (P≤0.0001). The ACA variants were more frequent among fetuses and neonates with symptomatic, rather than asymptomatic cytomegaly (P≤0.0001).Conclusions TLR4 and TLR9 polymorphisms may contribute to the development of congenital infection with HCMV in fetuses and neonates. The TLR9 2848 GA heterozygotic status possibly predisposes to HCMV infection, increasing the risk of congenital cytomegaly development.

Polymorphisms of nucleotide-binding oligomerization domain 2 (NOD2) gene in miniature dachshunds with inflammatory colorectal polyps

Inflammatory colorectal polyps (ICRPs) frequently occur in miniature dachshunds (MDs) in Japan, typically form multiple polyps with severe neutrophil infiltration. ICRPs are speculated as a novel, breed-specific canine inflammatory bowel disease. Pattern recognition receptors (PRRs) play an important role in the differentiation of pathogens from commensal bacteria and food antigens, and polymorphisms of various PRRs have been shown to be associated with human and canine IBD. We recently reported that the reactivity of nucleotide-binding oligomerization domain 2 (NOD2), toll-like receptor (TLR) 1/2, TLR2, and TLR2/6 are greater in ICRP-affected MDs than that in controls. Therefore, this study was aimed to investigate single nucleotide polymorphisms (SNPs) of PRRs associated with ICRPs in MDs. Mutational analysis of canine NOD2, TLR1, TLR2, and TLR6 genes was performed with six ICRP-affected MDs, five control MDs, and five healthy beagles. The mutational analysis identified 13 non-synonymous SNPs in NOD2, TLR1, TLR2, and TLR6 genes, of which six SNPs in NOD2 exon 3 were further analyzed in an association study using 63 ICRP-affected MDs, 82 control MDs, and 237 control dogs of various breeds. Four of the SNPs (A1532G, T1573C, C1688G, and G1880A of the NOD2 gene) were in Hardy–Weinberg equilibrium and in complete linkage disequilibrium in MDs, and their minor allele frequencies were significantly lower in ICRP-affected MDs than in control MDs (0.016 vs. 0.140, P=0.0002). The calculated inheritance model was an additive model (odds ratio=0.10, 95% confidence interval=0.02–0.45, P=0.0001), which indicates that the haplotype with minor alleles in these SNPs (A, T, C, and G in A1532G, T1573C, C1688G, and G1880A) possess a protective effect regarding the development of ICRPs. However, these SNPs were not specific for MDs, although the minor allele frequencies of these SNPs in control MDs were significantly lower than in other breed dogs. These results suggest that the identified four SNPs (A1532G, T1573C, C1688G, and G1880A in the NOD2 gene) may play a role in the pathogenesis of ICRPs in MDs. Because the majority of MDs and other breed dogs do not have the protective alleles, their absence may not be a specific cause of ICRPs in MDs but rather contribute to the development of inflammation.

Associations of toll-like receptor (TLR)-4 single nucleotide polymorphisms and rheumatoid arthritis disease progression: an observational cohort study.

To examine the associations of toll-like receptor (TLR)-4 single nucleotide polymorphisms (SNPs) with disease progression in rheumatoid arthritis (RA). A total of 1188 RA patients were genotyped for TLR4 SNPs (rs1927911, rs11536878, and rs4986790). Measures of disease activity were examined, including Disease Activity Score-28 (DAS28), Multidimensional Health Assessment Questionnaire (MD-HAQ), Clinical Disease Activity Index (CDAI), and Simplified Disease Activity Index (SDAI). Genetic associations with these longitudinal measures were examined using generalized estimating equations in both univariate and multivariate analyses. Analyses were then stratified by antigen specific anti-citrullinated peptide antibody (ACPA) status including antibody to citrullinated fibrinogen and citrullinated histone H2B. Disease activity measures progressed less over time in the homozygous minor allele group of rs1927911 including DAS28 (p<0.001), CDAI (p=0.008), and MD-HAQ (p=0.015) in univariate analysis and DAS28, CDAI and SDAI in multivariate analysis. Disease activity progression among those homozygous for the minor allele tended to be lower in the groups with positive ACPA though major differences by autoantibody status were not identified. There were no associations of TLR4 rs11536878 and rs4986790 SNPs with RA disease activity progression. In this population, TLR4 rs1927911 genotypes are associated with disease activity independent of other covariates.

Polymorphisms of Toll-Like Receptor 4 as a Risk Factor for Periodontitis: Meta-Analysis.

Toll-like receptors play an important role in the recognition of periopathogens. There are widely known polymorphisms of these receptors that may alter host susceptibility to periodontitis. Evaluating the association of TLR4 polymorphisms (Asp299 and Thr399Ile) with the occurrence of periodontitis and its two clinical types: chronic (CP) and aggressive (AgP) among Caucasians. A review of 4 electronic databases was made to identify studies that match the inclusion criteria for the meta-analysis and were published up to December 31, 2013. Fifteen studies met the inclusion criteria. For Asp299Gly polymorphism 1621 patients with periodontitis (1148 with CP and 473 with AgP) and 1755 individuals without clinical signs of periodontitis were included in the meta-analysis. The occurrence of polymorphism The 399Ile was evaluated among 1522 patients with periodontitis (1017 with CP and 505 with AgP) and 1461 subjects in the control group. The pooled OR with a random effects model for the Asp299Gly and chronic periodontitis was 1.35 (95% CI: 1.02-1.8, p = 0.038), indicating a possible association between this polymorphism and CP. Other published meta-analyzes showed no significant association between single nucleotide polymorphisms of TLR4 and periodontitis nor its clinical types. No publication bias was reported. Our meta-analysis showed statistically significant association between TLR4 Asp299Gly allele and increased susceptibility to chronic periodontitis.

The CD14 C-260T single nucleotide polymorphism (SNP) modulates monocyte/macrophage activation in treated HIV-infected individuals.

BackgroundHIV-infected individuals have an increased risk of cardiovascular disease (CVD). T-allele carriers of the CD14 C-260T single-nucleotide polymorphism (SNP) have reported increased expression of the LPS-binding receptor, CD14 and inflammation in the general population. Our aim was to explore the relationship of this SNP with monocyte/macrophage activation and inflammation and its association with sub-clinical atherosclerosis in HIV-infected individuals.MethodsPatients with no pre-existing CVD risk factors on suppressive antiretroviral therapy were recruited from University Malaya Medical Centre, Malaysia (n = 84). The CD14 C-260T and TLR4 SNPs, Asp299Gly and Thr399Ile were genotyped and soluble(s) CD14 and sCD163 and high-sensitivity C-reactive protein, hsCRP were measured in plasma. Subclinical atherosclerosis was assessed by measuring carotid intima media thickness (cIMT). The association between CD14 C-260T SNP carriage and cIMT was assessed in a multivariable quantile regression model where a p-value of <0.05 was considered significant.ResultsWe found the CD14 C-260T T-allele in 56% of the cohort and evidence of subclinical atherosclerosis in 27%. TT genotype was associated with higher sCD163 (p = 0.009) but only marginally higher sCD14 (p = 0.209) and no difference in hsCRP (p = 0.296) compared to CC/CT. In multivariable analysis, only Framingham risk score was independently associated with higher cIMT while lower sCD163 was trending towards significance. No association was found in TT-genotype carriers and cIMT measurements.ConclusionThe CD14 C-260T SNP was associated with increased monocyte activation but not systemic inflammation or cIMT in this HIV-infected cohort with low CVD risk profile.