Gene Thr399Ile Research Articles

The role of TLR-2 and TLR-4 gene polymorphisms in the development of sepsis in children with severe burns

Recently, many studies are based on the study of innate immunity genes, namely the role of TLRs in the development of various diseases. Severe burn injury is characterized by the development of hyperimmune reactions, which further leads to the development of multiple organ complications and sepsis. The aim of our study was to identify the frequency and prognostic value of polymorphism of TLR-2 Arg753Gln and TLR-4 Thr399 Ile genes and their role in the development of sepsis and MOD in children with severe burns. Materials and methods: genetic analysis of TLR-2 Arg 753 Gln and TLR-4 Thr399 Ile gene polymorphisms was performed in children with severe and extremely severe burns (n ​​= 22) who were treated in the anesthesiology department with intensive care beds. Results: as a result of the obtained data, the heterozygous genotype TLR-2 Arg 753 Gln was detected in 69.5% (n = 16), in 31.8% (n = 7) patients with burn injury polymorphism was not detected. In 13.6% (n = 3) cases, polymorphism was associated with sepsis and MOD. Sepsis and normal homozygous genotype were diagnosed in 4.5% (n = 1). Heterozygous genotype TLR-4 Thr399 Ile was observed in 18.2% (n = 4) patients, of which only 4.5% (n = 1) patients had polymorphism associated with sepsis and MOD. Analysis of the association of TLR 2 genotypes and markers of acute inflammation revealed statistically significant differences between the heterozygous TLR 2 Arg 753 Gln genotype and C-reactive protein (CRP) levels in the blood of patients on day 3 of burn disease. Conclusions: The study of the role of innate immune system genes is promising in predicting the development of sepsis and complications in severe burns and requires further careful study.

Disseminated cysticercosis: clinical spectrum, Toll-like receptor-4 gene polymorphisms and role of albendazole: A prospective follow-up of 60 cases with a review of 56 published cases.

In this study, we describe clinical and imaging spectrum, and the natural course of patients with disseminated cysticercosis. How albendazole affects the course of disease has also been evaluated. We assessed the Toll-like receptor-4 gene polymorphisms, to know the reason for the apparently higher prevalence of disseminated cysticercosis in India.Sixty consecutive patients with disseminated cysticercosis were enrolled. Sixty age-and-sex-matched healthy controls were also enrolled for the purpose of genetic study. Twenty patients, who gave consent, were treated with albendazole along with corticosteroids. Forty patients did not give consent for antiparasitic therapy. Assessment for Toll-like receptor-4 gene polymorphisms (Asp299Gly and Thr399Ile genes) was done. Patients were followed for 6 months. We also performed a literature search of cases published in English language using PubMed electronic database and analyzed 56 cases thus available.There was an increased risk (6.63 fold and 4.61 fold) of disseminated cysticercosis in the presence of Asp299Gly and Thr399Ile polymorphisms in Toll-like receptor-4, respectively. The allelic frequency of Gly (11% vs. 3%, P = 0.024, odds ratio [OR] = 3.52) and Ile alleles (11% vs. 2%, P = 0.009, OR = 4.738) in disseminated cysticercosis was high. Albendazole resulted in complete disappearance of all cerebral lesions in 35% (7/20) patients and reduction in lesion load in remaining 65% (13/20) patients. No significant change in number of cysticercal lesion was noted in patients who did not receive albendazole. No major adverse reaction following antiparasitic treatment was noted. Three deaths were recorded in patients who did not receive antiparasitic treatment.Of the 56 cases reported in PubMed, 33 patients received antiparasitic treatment with follow-up data available for 31 patients. Most (24) of these patients received albendazole. A significant clinical and/or imaging improvements, on follow up, were observed in 27 patients. Of the 4 deaths recorded, 3 had a heavy parasitic load and died after praziquantel therapy.Toll-like receptor-4 gene polymorphisms are associated with an increased susceptibility to disseminated cysticercosis, in the Indian population. Albendazole treatment seems to reduce the lesion load and improve symptoms.

Analysis of TLR4 (Asp299Gly and Thr399Ile) gene polymorphisms and mRNA level in patients with dengue infection: A case-control study

BackgroundDengue is a systemic viral infection that spreads to humans by the bite of infected Aedes mosquitoes. The secreted NS1 protein of dengue virus activates macrophages and human PBMCs via TLR4 and induce the release of pro-inflammatory cytokines which is responsible for the pathogenesis of disease. Mutations in TLR4 gene have been associated with the increased susceptibility to many viral, bacterial and parasitic diseases. ObjectiveTo study the impact of TLR4 Asp299Gly (rs4986790) and Thr399Ile (rs4986791) gene polymorphisms with susceptibility to dengue infection. MethodsA total of 120 dengue infected (57; DHF/DSS and 63; DF) and 200 healthy controls were included in the study. TLR4 Asp299Gly and Thr399Ile gene polymorphisms was studied by PCR-RFLP. Expression of TLR4 mRNA was evaluated by rRT-PCR. ResultsIndividuals with heterozygous genotype for TLR4 Asp299Gly and Thr399Ile polymorphisms had increased susceptibility to dengue infection (OR-1.70, 95% CI=1.01–2.86 P=0.042 and OR-2.17, 95% CI=1.10–4.28, P=0.024, respectively). The frequency of Gly and Ile alleles were higher in dengue patients as compared to controls (OR-1.67, 95% CI=1.05–2.64, P=0.029 and OR-2.20, 95% CI=1.19–4.07, P=0.011, respectively). IIe/Gly haplotype was associated with the risk of the disease when compared with controls (OR=3.15, 95% CI=1.09–9.09, P=0.035). The mRNA expression was higher in DF when compared with DHF/DSS and controls (P=0.040 and 0.009, respectively). ConclusionA higher expression of TLR4 mRNA was associated with DF. The TLR4 Asp299Gly and Thr399Ile gene polymorphisms were associated with the susceptibility of dengue infection probably by altering the immune response.

The effect of genetic polymorphisms of TLR2 and TLR4 in Turkish patients with coronary artery disease

Coronary artery disease (CAD), being a multifactorial disease process, has been suggested to be associated by the interaction of both environmental and genetic risk factors. Toll-like receptors (TLRs) are related to the receptors of the innate immune system which serves as the recognition of the conserved pathogen motifs and the activation of the signals that stimulate inflammatory genes. In this study, we investigated the relationship between the polymorphisms in the TLR2-Arg753Gly, TLR4-Asp299Gly and Thr399Ile gene and CAD. The study population consisted of 300 patients (149 men, 151 women) with angiographically documented CAD. The polymorphisms were genotyped by real time PCR. No association between TLR2-Arg677Trp or TLR4-Asp299Gly and -Thr399Ile gene polymorphisms and the presence or the severity of CAD was observed. On the other hand, the TLR2-Arg753Arg genotype seemed to have a protective effect against development of CAD (OR=0.17; 95% CI=0.04–0.83). Our findings suggest that TLR2-Arg753Gly polymorphism is associated with CAD susceptibility in Turkish patients.

O4-3.4 Neurocysticercosis in pig farming community from North India

IntroductionNeurocysticercosis (NCC) is a major public health problem, especially in the developing world and also increasingly reported in the developed world either due to migration of infected population or Taenia...

Analysis of association between TLR-4 Asp299Gly and Thr399Ile gene polymorphisms and chronic periodontitis in a sample of south Indian population

Background:To analyze the association between TLR-4 Asp299Gly and Thr399Ile gene polymorphisms and chronic periodontitis in a sample of south Indian population.Materials and Methods:Genomic DNA was obtained from peripheral blood of 60 patients with chronic periodontitis and 60 periodontally healthy subjects. TLR-4 Asp299Gly and Thr399Ile gene polymorphisms were genotyped by a polymerase chain reaction–restriction fragment length polymorphism method. The data were analyzed by a χ2-test and by relative risk estimation.Results:Thr399Ile alleles were found in 4% of chronic periodontitis patients and in 1% of periodontally healthy subjects. The prevalence of a Thr399Ile heterozygote was found to be 5% in the chronic periodontitis group and 1.67% in the periodontally healthy group, respectively. Homozygosity for TLR-4 Thr399Ile was seen in chronic periodontitis patients only, which was 1.67%. The TLR-4 Asp299Gly gene polymorphism was not detected in either chronic periodontitis or periodontally healthy groups.Conclusion:There is no significant association between TLR-4 Thr399Ile polymorphism and chronic periodontitis in a sample of south Indian population.

Toll-Like Receptor 4 Gene Polymorphisms and Preeclampsia: Lack of Association in a Caucasian Population

Preeclampsia is a multifactorial disorder with genetic and environmental components. As Toll-like receptor 4 (TLR4) has an essential role in innate immune response, which is exaggeratedly activated in preeclampsia, our aim was to investigate whether two single nucleotide polymorphisms (SNPs) of the TLR4 gene--Asp299Gly (A896G) and Thr399Ile (C1196T)--are associated with preeclampsia in a Caucasian population from Hungary. In a case-control study, we analyzed blood samples from 180 preeclamptic patients and 172 normotensive, healthy pregnant women with the polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) method. The linkage disequilibrium (LD) profile of the TLR4 gene was investigated and tag SNPs were identified using data from the International HapMap Project. There were no significant differences in the genotype and allele frequencies of Asp299Gly and Thr399Ile polymorphisms between the two study groups. Additionally, no significant difference was found in the distribution of the estimated haplotypes created by the two polymorphisms between the preeclamptic and the control group. Furthermore, no significant differences were detected in the genotype, allele and haplotype frequencies of Asp299Gly and Thr399Ile TLR4 SNPs between patients with mild and severe preeclampsia, between patients with late and early onset of the disease, or between preeclamptic patients with and without fetal growth restriction. In conclusion, we did not find an association between TLR4 Asp299Gly and Thr399Ile gene polymorphisms and preeclampsia. As the Thr399Ile polymorphism is a highly informative tag SNP of the TLR4 gene, our results suggest that variations in this genomic region are not associated with preeclampsia. Nevertheless, further studies are required with determination of fetal TLR4 genotypes to explore the role of TLR4 gene polymorphisms in the risk of preeclampsia, especially in ethnically different populations.

TLR2 Arg753Gly, TLR4 Asp299Gly and Thr399Ile gene polymorphisms are not associated with chronic periodontitis in a Turkish population

Toll-like receptor (TLR) gene polymorphisms could affect the host's ability to respond to microbial pathogens. In this case-control study, the association of TLR2 and TLR4 gene polymorphisms with chronic periodontitis (CP) was investigated. Genomic DNA was obtained from the peripheral blood of 83 patients with CP and 106 periodontally healthy subjects. The TLR2 Arg753Gly, Arg677Trp and TLR4 Asp299Gly, Thr399Ile gene polymorphisms were genotyped by the polymerase chain reaction-restriction fragment length polymorphism method. The data were analysed by a chi2 test, logistic regression analysis and the Mann-Whitney U test. The 753Gln allele was found in 6.1% of the CP patients as compared with 6.6% in the control group (p>0.05). The frequency of the 299Gly and 399Ile allele was 2.4% and 1.8% in CP patients. For the healthy subjects, the frequency was 2.8% for the 299Gly and 2.5% for the 399Ile allele (p>0.05). None of the CP patients or healthy subjects showed homozygosity for the TLR2 and TLR4 alleles. Percentage of sites with bleeding on probing and plaque were significantly higher in 299Gly-positive patients compared with 299Gly-negative patients (p<0.05). These results showed that the TLR2 and TLR4 gene polymorphisms studied are not associated with susceptibility to CP in Turkish patients.