TREM-1 as a Marker of Multiple Organ Failure in Cardiac Surgery.

Systemic inflammatory response syndrome (SIRS) frequently accompanies early postoperative period after cardiac surgery and in some cases is complicated by multiple organ failure (MOF). Inherited variation in the innate immune response genes (e.g., TREM1) is among the major factors determining the development of SIRS and the risk of MOF. This research was aimed to study whether the polymorphisms within the TREM1 gene are associated with MOF after the coronary artery bypass graft (CABG) surgery. Here we enrolled 592 patients who underwent CABG surgery in the Research Institute for Complex Issues of Cardiovascular Diseases (Kemerovo, Russia) and documented 28 cases of MOF. Genotyping was performed by allele-specific PCR using TaqMan probes. In addition, we measured serum soluble triggering receptor expressed on myeloid cells 1 (sTREM-1) using enzyme-linked immunosorbent assay. Five polymorphisms (rs1817537, rs2234246, rs3804277, rs7768162 andrs4711668) within the TREM1 gene were significantly associated with MOF. Patients with MOF had higher serum sTREM-1 as compared with those without MOF at both pre- and post-intervention stages. Serum sTREM-1 was associated with the rs1817537,rs2234246 and rs3804277 polymorphisms within the TREM1 gene. Minor alleles within the TREM1 gene define the level of serum sTREM-1 and are associated with MOF after CABG surgery.

IL18-family Genes Polymorphism Is Associated with the Risk of Myocardial Infarction and IL18 Concentration in Patients with Coronary Artery Disease.

BACKGROUND: Atherogenesis is mainly determined by endothelial dysfunction, lipid metabolism disorders and inflammation. The atherogenesis-related inflammatory process is a complex interaction between serum blood lipoproteins, inflammatory cells, endothelial and smooth muscle cells and extracellular matrix; the role of chronic inflammation in atherogenesis was proposed. MATERIAL AND METHODS: A pathogenetic role of polymorphism in NF-kB pathway genes in coronary artery disease and associated pathological conditions has been suggested in a case-control retrospective study. 260 coronary artery disease patients permanently living in a large industrial region of Russian Federation (Kemerovo region) were recruited in the study. We examined nine single nucleotide polymorphisms in IL18, IL18R1 and IL18RAP genes by polymerize chain reaction; and serum blood level of IL18 by enzyme-linked immunosorbent assay. RESULTS: Polymorphic variants rs13015714 (IL18R1) and rs917997 (IL18RAP) are associated with the risk of myocardial infarction and high serum levels of IL18. Minor alleles of rs13015714 and rs917997 sites are associated with high risk of developing multifocal atherosclerosis and arterial hypertension in patients with stable coronary artery disease after myocardial infarction. CONCLUSIONS: Thus, polymorphism in the genes of IL18 receptor is determine the IL18 contents and important in the development of coronary atherosclerosis, associated pathological conditions and the risk of acute coronary events; prospective monitoring of patients with early clinical signs of adverse events is required to confirm the role of IL18, IL18R1, and IL18RAP genes polymorphism in atherogenesis.

Inherited Variation in Cytokine, Acute Phase Response, and Calcium Metabolism Genes Affects Susceptibility to Infective Endocarditis.

Infective endocarditis (IE) is a septic inflammation of the endocardium. Recognition of microbial patterns, cytokine and acute phase responses, hemostasis features, and alterations in plasma lipid and calcium profile all have been reported to affect pathogenesis and clinical course of IE. Having recruited 123 patients with IE and 300 age-, sex-, and ethnicity-matched healthy blood donors, we profiled their genomic DNA for 35 functionally significant polymorphisms within the 22 selected genes involved in the abovementioned pathways, with the further genetic association analysis. We found that the G/A genotype of the rs1143634 polymorphism within the IL1B gene, the G/T genotype of the rs3212227 polymorphism within the IL12B gene, the A/G genotype of the rs1130864 polymorphism within the CRP gene, and the G allele of the rs1801197 polymorphism within the CALCR gene were associated with a decreased risk of IE whereas the T/T genotype of the rs1205 polymorphism within the CRP gene was associated with a higher risk of IE. Furthermore, heterozygous genotypes of the rs1143634 and rs3212227 polymorphisms were associated with the higher plasma levels of IL-1ß and IL-12, respectively. Our results indicate that inherited variation in the cytokine, acute phase response, and calcium metabolism pathways may be linked to IE.

A Genomics-Based Model for Prediction of Severe Bioprosthetic Mitral Valve Calcification.

Severe bioprosthetic mitral valve calcification is a significant problem in cardiovascular surgery. Unfortunately, clinical markers did not demonstrate efficacy in prediction of severe bioprosthetic mitral valve calcification. Here, we examined whether a genomics-based approach is efficient in predicting the risk of severe bioprosthetic mitral valve calcification. A total of 124 consecutive Russian patients who underwent mitral valve replacement surgery were recruited. We investigated the associations of the inherited variation in innate immunity, lipid metabolism and calcium metabolism genes with severe bioprosthetic mitral valve calcification. Genotyping was conducted utilizing the TaqMan assay. Eight gene polymorphisms were significantly associated with severe bioprosthetic mitral valve calcification and were therefore included into stepwise logistic regression which identified male gender, the T/T genotype of the rs3775073 polymorphism within the TLR6 gene, the C/T genotype of the rs2229238 polymorphism within the IL6R gene, and the A/A genotype of the rs10455872 polymorphism within the LPA gene as independent predictors of severe bioprosthetic mitral valve calcification. The developed genomics-based model had fair predictive value with area under the receiver operating characteristic (ROC) curve of 0.73. In conclusion, our genomics-based approach is efficient for the prediction of severe bioprosthetic mitral valve calcification.

Association of TLR and TREM-1 gene polymorphisms with atherosclerosis severity in a Russian population.

Local vascular immune response is primarily initiated via Toll-like receptors (TLRs) and triggering receptor expressed on myeloid cells-1 (TREM-1). We previously showed that certain TLR and TREM-1 gene polymorphisms are associated with coronary artery disease (CAD). Therefore, we hypothesized that these gene polymorphisms are associated with atherosclerosis severity. This study included 292 consecutive patients with CAD who were admitted to the Research Institute for Complex Issues of Cardiovascular Diseases (Kemerovo, Russian Federation) during 2011-2012. Sample genotyping was performed in 96-well format using the TaqMan SNP genotyping assay. We found that C/C genotype of the rs3804099 polymorphism within TLR2 gene and T/T genotype of the rs4711668 polymorphism within TREM-1 gene were significantly associated with severe coronary atherosclerosis while C allele of the rs5743551 polymorphism within TLR1 gene, A/G genotype of the rs4986790 polymorphism and C/T genotype of the rs4986791 polymorphism within TLR4 gene, and C allele of the rs3775073 polymorphism within TLR6 gene were significantly associated with severe noncoronary atherosclerosis. However, A/A genotype of the rs5743810 polymorphism within TLR6 gene was significantly associated with mild noncoronary atherosclerosis. We conclude that certain TLR and TREM-1 gene polymorphisms are significantly associated with atherosclerosis severity in a Russian population.

An association between single nucleotide polymorphisms within TLR and TREM-1 genes and infective endocarditis.

Infective endocarditis (IE) is an inflammatory condition of the lining of the heart chambers and valves, which is generally caused by bacteria. Toll-like receptors (TLRs) and Triggering receptor expressed on myeloid cells (TREMs) are key effectors of the innate system that play a significant role in the recognition of infectious agents, particularly, bacteria. We hypothesised that inherited variation in TLR and TREM-1 genes may affect individual susceptibility to IE. The distribution of genotypes and alleles of the TLR1 (rs5743551, rs5743611), TLR2 (rs3804099, rs5743708), TLR4 (rs4986790, rs4986791), TLR6 (rs3775073, rs5743810), and TREM-1 (rs1817537, rs3804277, rs6910730, rs7768162, rs2234246, rs4711668, rs9471535, rs2234237) gene polymorphisms was investigated in 110 Caucasian (Russian) subjects with IE and 300 age-, sex-, and ethnicity-matched healthy blood donors. Odds ratios with 95% confidence intervals were calculated. We found that C/C genotype of the rs3775073 polymorphism within TLR6 gene was associated with a decreased risk of IE (OR=0.51, 95% CI=0.26-0.97, P=0.032) according to the recessive model; however, we observed no association between the other investigated SNPs within TLR and TREM-1 genes and IE. Further in-depth investigations in this field are necessary to shed the light on the impact of inherited variation within innate immune response genes on the development of IE.

Association of TLR and TREM-1 gene polymorphisms with risk of coronary artery disease in a Russian population.

Atherosclerosis, manifesting itself as acute coronary syndrome, stroke, and peripheral arterial diseases, is a chronic progressive inflammatory disease which is driven by responses of both innate and adaptive immunity. Toll-like receptors (TLRs) and Triggering Receptor Expressed on Myeloid Cells-1 (TREM-1) are important effectors of the innate immune system, and polymorphisms within genes encoding them may increase risk of occurrence of various pathologies including cardiovascular disorders. Thus, we carried out a genetic association study on the sample of 702 consecutive Caucasian (Russian) patients with coronary artery disease (CAD) and 300 age-, sex-, and ethnicity-matched healthy controls. We revealed that the C/C genotype of the TLR1 rs5743551 polymorphism was significantly associated with a reduced risk of CAD according to the recessive model (OR=0.41, 95% CI=0.20-0.84, P=0.017, adjusted by age and gender). Concerning TREM-1 gene polymorphisms, we found that A/A genotype of the rs2234237 polymorphism, the G/G genotype of the rs6910730 polymorphism, the C/C genotype of the rs9471535 polymorphism, and the T/T genotype of the rs4711668 polymorphism were significantly associated with elevated CAD risk according to the recessive model (OR=5.52, 95% CI=1.17-25.98, P=0.011; OR=4.28, 95% CI=1.09-16.81, P=0.021; OR=5.55, 95% CI=1.18-26.09, P=0.011, and OR=1.66, 95% CI=1.10-2.52, P=0.014, respectively, adjusted by age and gender). Conversely, the G allele of the rs1817537 polymorphism, the T allele of the rs2234246 polymorphism, and the T allele of the rs3804277 polymorphism significantly correlated with similarly decreased risk of CAD according to the dominant model (OR=0.57, 95% CI=0.40-0.81, P=0.0013; OR=0.59, 95% CI=0.42-0.84, P=0.003, and OR=0.58, 95% CI=0.41-0.81, P=0.0014, respectively, adjusted by age and gender). We conclude that certain TLR and TREM-1 gene polymorphisms may be associated with CAD in Russian population; however, their significance as predictive and pathogenic markers of CAD should be interpreted with caution in other populations.