Sepsis In Chinese Han Population Research Articles

Genetic variation in the tissue factor gene is associated with clinical outcome in severe sepsis patients.

IntroductionActivation of inflammation and coagulation was closely related and mutually interdependent in sepsis. Tissue factor (TF) and its endogenous inhibitor, tissue factor pathway inhibitor (TFPI) was the main regulators of the initiation of coagulation process. Altered plasma levels of TF and TFPI have been related to worse outcome in sepsis. The objective of this study was to investigate whether single nucleotide polymorphisms (SNPs) in the TF and TFPI genes were associated with risk and outcome for patients with severe sepsis.MethodsSeventeen SNPs in TF and TFPI were genotyped in samples of sepsis (n =577) and severe sepsis patients (n =476), and tested for association in this case–control collection. We then investigated correlation between the associated SNPs and the mRNA expression, and protein level of the corresponding gene. The mRNA levels of TF were determined using real-time quantitative reverse transcription-polymerase chain reaction and the soluble plasma levels of TF were measured using enzyme linked immunosorbent assay (ELISA) method.ResultsAssociation analysis revealed that three TF SNPs in perfect linkage disequilibrium, rs1361600, rs3917615 and rs958587, were significantly associated with outcome of severe sepsis. G allele frequency of rs1361600 in survivor patients was significantly higher than that in nonsurvivor severe sepsis patients (P =4.91 × 10-5, odds ratio (OR) =0.48, 95% confidence interval (CI) 0.33 to 0.69). The association remained significant after adjustment for covariates in multiple logistic regression analysis and for multiple comparisons. Lipopolysaccharide-induced TF-mRNA expression levels in peripheral blood mononuclear cells from subjects carrying rs1361600 AG and GG genotypes, were significantly lower than those subjects carrying AA genotype (P =0.0012). Moreover, severe sepsis patients of GG and GA genotypes showed lower serum levels of TF than patients with AA genotype (Padj =0.02). The plasma levels of TF were also associated with outcome of severe sepsis patients (Padj =0.01). However, genotype and allele analyses did not show any significant difference between sepsis and severe sepsis patients.ConclusionsOur findings indicate that common genetic variation in TF was significantly associated with outcome of severe sepsis in Chinese Han population.Electronic supplementary materialThe online version of this article (doi:10.1186/s13054-014-0631-9) contains supplementary material, which is available to authorized users.

Genomic polymorphisms within alpha 7 nicotinic acetylcholine receptor and severe sepsis in Chinese Han population

Alpha 7 nicotinic acetylcholine receptor, a kind of ligand-gated ion channel mainly expressed in macrophages, plays a crucial role in improving survival in sepsis via suppressing proinflammatory cytokines. The predisposition of genomic polymorphisms within alpha 7 nicotinic acetylcholine receptor gene (CHRNA7) to sepsis has not been investigated. The current association study was performed to analyse six common genetic variations within 5'-upstream region of CHRNA7 gene in 229 patients with severe sepsis and 267 controls. Neither allelic frequencies nor genotype distributions were significantly different between patients and controls, as well as between surviving and nonsurviving patients. The frequencies of estimated haplotypes were also comparable between above defined groups. The present study suggests that genomic polymorphisms in the 5'-upstream region of CHRNA7 gene may not be a major risk factor for severe sepsis in Chinese Han population.

Increased Genomic Copy Number of DEFA1/DEFA3 Is Associated with Susceptibility to Severe Sepsis in Chinese Han Population

Human neutrophil peptides 1-3 are endogenous cationic antimicrobial peptides implicated in host defense against microbes. The genes encoding human neutrophil peptides 1-3 (DEFA1/DEFA3) exhibit copy number variations. This study was designed to determine whether DEFA1/DEFA3 copy number variations conferred susceptibility to infection-induced complications such as severe sepsis. This case-control study was performed in 179 patients with severe sepsis and 233 healthy blood donors and was replicated in an independent cohort of 112 cases and 118 controls. Plasma levels of human neutrophil peptides 1-3, tumor necrosis factor-alpha, interleukin-6, and interleukin-10 were detected. The genotype of DEFA1/DEFA3 with more than eight copies was more frequent in patients with severe sepsis than in controls (55.9% vs. 31.3%; P = 1.13 x 10, odds ratio 2.77, 95% confidence interval 1.85-4.16). After adjustment for age and gender, logistic regression analysis confirmed the association of the genotype of more than eight copies with an increased risk of severe sepsis (P = 2.25 x 10, odds ratio 2.66, 95% confidence interval 1.69-4.19). This established association was replicated in a second age- and gender-matched case-control cohort (P = 0.02, odds ratio 1.90, 95% confidence interval 1.11-3.27). Furthermore, compared with those with fewer copies, the patients carrying more than eight copies of DEFA1/DEFA3 presented significantly lower plasma levels of human neutrophil peptides 1-3, tumor necrosis factor-alpha, interleukin-6, and interleukin-10 (P = 0.039, 0.017, 0.030, and 0.029, respectively). DEFA1/DEFA3 is an important genetic component participating in host immune response to severe sepsis. A higher copy number of DEFA1/DEFA3 (>8 copies) is significantly associated with the risk of severe sepsis.

Protein C -1641A/-1654C haplotype is associated with organ dysfunction and the fatal outcome of severe sepsis in Chinese Han population

Activation of protein C plays an important role in modulating coagulation as well as inflammation during severe sepsis. The baseline of activated protein C level in patients with severe sepsis showed interindividual variability between survivors and nonsurvivors, and the decreased level of protein C correlated with organ dysfunction and poor outcome. However, there are limited data concerning the genetic predisposition of individuals carrying two functional polymorphisms -1641A>G and -1654C>T within protein C gene to sepsis. Here we investigated the impact of these two variations on the development of severe sepsis in 240 patients with severe sepsis and 323 healthy controls using direct sequencing. After Bonferroni correction for multiple comparisons, -1641A/-1654C haplotype was significantly associated with the fatal outcome of severe sepsis (P = 0.008, OR 1.739, 95% CI 1.165-2.595), which was confirmed by multiple logistic regression analysis (P = 0.024, OR 2.090, 95% CI 1.101-3.967). Compared to patients without carrying -1641A/-1654C haplotype, the -1641A/-1654C haplotype carriers showed higher SOFAmax scores (10.3 +/- 5.2 vs. 9.0 +/- 4.5; P = 0.014) and more hepatic dysfunction (P = 0.004, OR 2.270, 95% CI 1.312-3.930). These findings suggest that protein C haplotype -1641A/-1654C is associated with organ dysfunction and is an independent risk factor for the fatal outcome of severe sepsis in Chinese Han population.

Genomic variations within DEFB1 are associated with the susceptibility to and the fatal outcome of severe sepsis in Chinese Han population

Sepsis is a systemic inflammatory response syndrome to infection. Human beta-defensin 1 (DEFB1) is a multifunctional mediator in infection and inflammation, which has been largely explored in ex vivo studies. The present case-control study was designed to investigate whether DEFB1 genomic variations are associated with the susceptibility to and the outcome of severe sepsis in 211 patients with severe sepsis and 157 ethnic-matched healthy controls. After correcting for multiple testing, the -44G/C was the only polymorphism found to show significant associations with both the susceptibility to and the fatal outcome of severe sepsis (P=0.0049, odd ratio (OR) 1.971 and P=0.002, OR 2.406, respectively). Haplotype -20A/-44C/-52G showed a protective role against severe sepsis (P=0.0066, OR 0.6751), whereas haplotype -20G/-44G/-52G served as a risk factor for the fatal outcome of severe sepsis (P=0.0052, OR 2.427). These findings provide further evidence that beta-defensin 1 may play a role in the pathogenesis of severe sepsis.