EFFECTS OF CD14-159 C/T POLYMORPHISM ON CD14 EXPRESSION AND THE BALANCE BETWEEN PROINFLAMMATORY AND ANTI-INFLAMMATORY CYTOKINES IN WHOLE BLOOD CULTURE

Maternal Perinatal Dietary Patterns Affect Food Allergy Development in Susceptible Infants

BACKGROUND

The increasing incidence of food allergy (FA) can be attributed to interactions between genes and the environment, but these interactions are not yet fully clear.

OBJECTIVE

We aimed to evaluate the interaction between infant genetic variations and maternal dietary patterns to identify risk factors in the development of FA.

METHODS

We used the Cohort for Childhood Origin of Asthma and allergic diseases birth cohort of 1628 infants, born between 2007 and 2015. Maternal dietary intakes were assessed at 26 weeks of pregnancy using a food frequency questionnaire and grouped according to 5 dietary patterns. Infant cord blood samples were genotyped at 12 loci.

RESULTS

Among 1628 infants, 147 (9.0%) were diagnosed with FA based on history. A maternal confectionery diet characterized by a higher intake of baked and sugary products during pregnancy was associated with a higher prevalence of FA (adjusted odds ratio [OR] = 1.517, P = .02); this dietary pattern tended to be higher in trans fat (r = 0.498, P < .001). Development of FA was associated with longer periods of breastfeeding (adjusted OR = 1.792, P = .03), and this dietary pattern was more significantly related to the development of FA in infants with the homozygous TT genotype of CD14 (rs2569190) and more than 1 copy of GSTM1 and GSTT1.

CONCLUSIONS

A maternal confectionery diet during pregnancy that majorly consists of baked and sugary products, combined with a longer ensuing period of breastfeeding, may lead to the development of FA, suggesting a harmful effect of trans fats in the infant. Polymorphisms in CD14 and GST in the infant influence FA susceptibility.

High-dose acute exposure of paraquat induces injuries of swim bladder, gastrointestinal tract and liver via neutrophil-mediated ROS in zebrafish and their relevance for human health risk assessment

The exact toxicological mechanisms of paraquat (PQ) poisoning are not entirely clear, especially on the high-level acute exposure. To assess the health risk of PQ, especially to suicidal individuals, accidental ingestion eaters, occupational groups, and special multitude, firstly we explored the acute toxic effect and the possible mechanisms of high-level exposure of PQ using zebrafish. The mainly target organs of PQ were swim bladder which is the homolog of the mammalian lung, followed by gastrointestinal tract and liver. Morphological malformations which were further defined by histopathologic examination include smaller size, fibrosis and inflammatory cell invasion for swim bladder; irregularly arranged or dissolved epithelial folds, loss of villous architecture, and ecclasis of mucosal cells in a smaller lumen for gastrointestinal tract; as well as smaller size, degeneration, fibrous proliferation, atrophy for liver. In addition, PQ enhanced leukocyte recruitment (neutrophil migrated first, followed by macrophage) into swim bladder and induced ROS which can be scavenged by glutathione. Moreover, qRT-PCR results showed that PQ increased the expression level of genes involved in the inflammatory response, such as L-1β, IL-6, IL-8, TNF-α, TNF-β, IFN-1, TGF-β, and NF-kB. For the first time, our results demonstrated that acute exposure of PQ induced pulmonary toxicity which was followed by gastrointestinal and hepatic toxicity via neutrophil-mediated ROS in zebrafish. In summary, these findings generated here will contribute to our better understanding of characteristics of PQ acute poisoning and can provide valuable information on better PQ poisoning treatments, occupational disease prevention, and providing theoretical foundation for risk management measures.

Quantitative Simulations Predict Treatment Strategies Against Fungal Infections in Virtual Neutropenic Patients

The condition of neutropenia, i.e., a reduced absolute neutrophil count in blood, constitutes a major risk factor for severe infections in the affected patients. Candida albicans and Candida glabrata are opportunistic pathogens and the most prevalent fungal species in the human microbiota. In immunocompromised patients, they can become pathogenic and cause infections with high mortality rates. In this study, we use a previously established approach that combines experiments and computational models to investigate the innate immune response during blood stream infections with the two fungal pathogens C. albicans and C. glabrata. First, we determine immune-reaction rates and migration parameters under healthy conditions. Based on these findings, we simulate virtual patients and investigate the impact of neutropenic conditions on the infection outcome with the respective pathogen. Furthermore, we perform in silico treatments of these virtual patients by simulating a medical treatment that enhances neutrophil activity in terms of phagocytosis and migration. We quantify the infection outcome by comparing the response to the two fungal pathogens relative to non-neutropenic individuals. The analysis reveals that these fungal infections in neutropenic patients can be successfully cleared by cytokine treatment of the remaining neutrophils; and that this treatment is more effective for C. glabrata than for C. albicans.

Association of CD14 rs2569190 polymorphism with mortality in shock septic patients who underwent major cardiac or abdominal surgery: A retrospective study

The aim of this study was to investigate the relationship between the CD14 rs2569190 polymorphism and death related to septic shock in white European patients who underwent major cardiac or abdominal surgery. We carried out a retrospective study in 205 septic shock patients. The septic shock diagnosis was established by international consensus definitions. The outcome variable was the death within 28, 60 and 90 days after septic shock diagnosis. The CD14 rs2569190 polymorphism was analyzed by Agena Bioscience’s MassARRAY platform. For the genetic association analysis with survival was selected a recessive inheritance model (GG vs. AA/AG). One hundred thirteen out of 205 patients (55.1%) died with a survival median of 39 days (95%CI = 30.6; 47.4). Patients with rs2569190 GG genotype had shorter survival probability than rs2569190 AA/AG genotype at 60 days (62.3% vs 50%; p = 0.035), and 90 days (62.3% vs 52.6%; p = 0.046). The rs2569190 GG genotype was associated with increased risk of septic shock-related death in the first 60 days (adjusted hazard ratio (aHR) = 1.67; p = 0.016) and 90 days (aHR = 1.64; p = 0.020) compared to rs2569190 AA/AG genotype. In conclusion, the presence of CD14 rs2569190 GG genotype was associated with death in shock septic patients who underwent major surgery. Further studies with bigger sample size are required to verify this relationship.

Impact of CD14 Polymorphisms on Anti-Apolipoprotein A-1 IgG-Related Coronary Artery Disease Prediction in the General Population

Objective—

We aimed to determine whether autoantibodies against apoA-1 (apolipoprotein A-1; anti-apoA-1 IgG) predict incident coronary artery disease (CAD), defined as adjudicated incident myocardial infarction, angina, percutaneous coronary revascularization, or bypass grafting, in the general population. We further investigated whether this association is modulated by a functional CD14 receptor single nucleotide polymorphism.

Approach and Results—

In a prospectively studied, population-based cohort of 5220 subjects (mean age 52.6±10.7 years, 47.4% males), followed over a median period of 5.6 years, subjects positive versus negative for anti-apoA-1 IgG presented a total CAD rate of 3.9% versus 2.8% ( P =0.077) and a nonfatal CAD rate of 3.6% versus 2.3% ( P =0.018), respectively. After multivariate adjustment for established cardiovascular risk factors, the hazard ratios of anti-apoA-1 IgG for total and nonfatal CAD were: hazard ratio=1.36 (95% confidence interval, 0.94–1.97; P =0.105) and hazard ratio=1.53 (95% confidence interval, 1.03–2.26; P =0.034), respectively. In subjects with available genetic data for the C260T rs2569190 single nucleotide polymorphism in the CD14 receptor gene (n=4247), we observed a significant interaction between anti-apoA-1 IgG and rs2569190 allele status with regards to CAD risk, with anti-apoA-1 IgG conferring the highest risk for total and nonfatal CAD in non-TT carriers, whereas being associated with the lowest risk for total and nonfatal CAD in TT homozygotes ( P for interaction =0.011 and P for interaction =0.033, respectively).

Conclusions—

Anti-apoA-1 IgG are independent predictors of nonfatal incident CAD in the general population. The strength of this association is dependent on a functional polymorphism of the CD14 receptor gene, a finding suggesting a gene–autoantibody interaction for the development of CAD.

The CD14 rs2569190 TT Genotype Is Associated with an Improved 30-Day Survival in Patients with Sepsis: A Prospective Observational Cohort Study

According to previous investigations, CD14 is suggested to play a pivotal role in initiating and perpetuating the pro-inflammatory response during sepsis. A functional polymorphism within the CD14 gene, rs2569190, has been shown to impact the pro-inflammatory response upon stimulation with lipopolysaccharide, a central mediator of inflammation in sepsis. In this study, we hypothesized that the strong pro-inflammatory response induced by the TT genotype of CD14 rs2569190 may have a beneficial effect on survival (30-day) in patients with sepsis. A total of 417 adult patients with sepsis (and of western European descent) were enrolled into this observational study. Blood samples were collected for rs2569190 genotyping. Patients were followed over the course of their stay in the ICU, and the 30-day mortality risk was recorded as the primary outcome parameter. Sepsis-related organ failure assessment (SOFA) scores were quantified at sepsis onset and throughout the observational period to monitor organ failure as a secondary variable. Moreover, organ support-free days were evaluated as a secondary outcome parameter. TT-homozygous patients were compared to C-allele carriers. Kaplan-Meier survival analysis revealed a higher 30-day mortality risk among C-allele carriers compared with T homozygotes (p = 0.0261). To exclude the effect of potential confounders (age, gender, BMI and type of infection) and covariates that varied at baseline with a p-value < 0.2 (e.g., comorbidities), we performed multivariate Cox regression analysis to examine the survival time. The CD14 rs2569190 C allele remained a significant covariate for the 30-day mortality risk in the multivariate analysis (hazard ratio, 2.11; 95% CI, 1.08-4.12; p = 0.0282). The 30-day mortality rate among C allele carriers was 23%, whereas the T homozygotes had a mortality rate of 13%. Additionally, an analysis of organ-specific SOFA scores revealed a significantly higher SOFA-Central nervous system score among patients carrying the C allele compared with T-homozygous patients (1.9±1.1 and 1.6±1.0, respectively; p = 0.0311). In conclusion, CD14 rs2569190 may act as a prognostic variable for the short-term outcome (30-day survival) in patients with sepsis.

A virtual infection model quantifies innate effector mechanisms and Candida albicans immune escape in human blood

Candida albicans bloodstream infection is increasingly frequent and can result in disseminated candidiasis associated with high mortality rates. To analyze the innate immune response against C. albicans, fungal cells were added to human whole-blood samples. After inoculation, C. albicans started to filament and predominantly associate with neutrophils, whereas only a minority of fungal cells became attached to monocytes. While many parameters of host-pathogen interaction were accessible to direct experimental quantification in the whole-blood infection assay, others were not. To overcome these limitations, we generated a virtual infection model that allowed detailed and quantitative predictions on the dynamics of host-pathogen interaction. Experimental time-resolved data were simulated using a state-based modeling approach combined with the Monte Carlo method of simulated annealing to obtain quantitative predictions on a priori unknown transition rates and to identify the main axis of antifungal immunity. Results clearly demonstrated a predominant role of neutrophils, mediated by phagocytosis and intracellular killing as well as the release of antifungal effector molecules upon activation, resulting in extracellular fungicidal activity. Both mechanisms together account for almost of C. albicans killing, clearly proving that beside being present in larger numbers than other leukocytes, neutrophils functionally dominate the immune response against C. albicans in human blood. A fraction of C. albicans cells escaped phagocytosis and remained extracellular and viable for up to four hours. This immune escape was independent of filamentation and fungal activity and not linked to exhaustion or inactivation of innate immune cells. The occurrence of C. albicans cells being resistant against phagocytosis may account for the high proportion of dissemination in C. albicans bloodstream infection. Taken together, iterative experiment–model–experiment cycles allowed quantitative analyses of the interplay between host and pathogen in a complex environment like human blood.

Candida albicans is the most important fungal pathogen in nosocomial bloodstream infections. So far little is known about the interplay of different cellular and non-cellular immune mechanisms mediating the protective response against C. albicans in blood. The in vivo scenario of C. albicans infection can be mimicked by human whole-blood infection assays to analyze the innate immune response against this pathogen. These experiments reveal the time-evolution of certain mechanisms while leaving the values of other quantities in the dark. To shed light on quantities that are not experimentally accessible, we exploited the descriptive and predictive power of mathematical models to estimate these parameters. The combination of experiment and theory enabled us to identify and quantify the main course of the immune response against C. albicans in human blood. We quantified the central role of neutrophils in the defence against this fungal pathogen, both directly by phagocytosis and indirectly by secreting antimicrobial factors inducing extracellular killing. Other findings include the distribution of C. albicans cells in neutrophils and monocytes as well as the immune escape of C. albicans cells in the course of infection.

Association between CD14 promoter -159C/T polymorphism and the risk of sepsis and mortality: a systematic review and meta-analysis

Background

Recent studies on the association between CD14-159C/T polymorphism and sepsis showed inconclusive results. Accordingly, we conducted a comprehensive literature search and a meta-analysis to determine whether the CD14-159C/T polymorphism conferred susceptibility to sepsis or was associated with increased risk of death from sepsis.

Methodology

Data were collected from the following electronic databases: PubMed, Embase, Medline, Web of Knowledge, and HuGE Navigator, with the last report up to June 15, 2012. The odds ratio (OR) and 95% confidence interval (CI) were used to assess the strength of association. We summarized the data on the association between CD14-159C/T polymorphism and sepsis in the overall population and subgroup by ethnicity and sepsis subtype.

Principal Findings

A total of 16 studies on sepsis morbidity (1369 cases and 2382 controls) and 4 studies on sepsis mortality (731 sepsis patients) met the inclusion criteria for meta-analysis. Overall analysis showed no strong evidences of association with sepsis susceptibility under any genetic model. However, slight associations were found in Asian populations (dominant model: OR = 1.38, 95%CI = 0.96–1.98, P = 0.08) and septic shock patients (dominant model: OR = 1.72, 95%CI 1.05–2.83, P = 0.03; allelic model: OR = 1.52, 95%CI 1.09–2.12, P = 0.01) in the stratified analysis. Moreover, there was borderline association between CD14-159C/T and sepsis mortality under the dominant genetic model (OR = 1.44, 95%CI = 0.98–2.11, P = 0.06).

Conclusions/Significance

This meta-analysis suggests that the CD14-159C/T polymorphism may not be a significant susceptibility factor in the risk of sepsis and mortality. Only weak associations were observed in Asian populations and septic shock patients. More studies based on larger sample sizes and homogeneous sepsis patients are needed to confirm these findings.

Helicobacter pylori Infection Enhances Gastric Mucosal Inflammation in Individuals Carrying the 260-T Allele of the CD14 Gene

BACKGROUND/AIMS

We aim to evaluate the association between promoter polymorphism of the clusters of differentiation 14 (CD14) gene and Helicobacter pylori-induced gastric mucosal inflammation in a healthy Korean population.

METHODS

The study population consisted of 267 healthy subjects who visited our hospital for free nationwide gastric cancer screening. Promoter polymorphism at -260 C/T of the CD14 gene was determined by polymerase chain reaction and restriction fragment length polymorphism analysis. The severity of gastric mucosal inflammation was estimated by a gastritis score based on the sum of the values of the grade and activity of the gastritis. Expression of soluble CD14 (sCD14) was assessed by quantitative sandwich ELISA.

RESULTS

CD14 polymorphism was not associated with H. pylori infection. There were no significant differences in gastritis scores among the genotype subgroups, but subjects carrying the CD14 -260 CT/TT genotype had significantly higher sCD14 levels than those carrying the CC genotype. Subjects with the 260-T allele of the CD14 gene and H. pylori infection had significantly higher sCD14 levels than those with the same genotype but without infection.

CONCLUSIONS

In individuals with the T allele at the -260 site of the promoter region of the CD14 gene, H. pylori infection accentuates gastric mucosal inflammation.

The synergy of -260T T CD14 and -308GG TNF-α genotypes in survival of critically ill patients

Literature suggests that the analysis of several polymorphic genetic markers is more informative than the analysis of a single polymorphism. In this study, we tested whether the shared inheritance of TLR2 and TLR4 and TNF-α allelic variants may act in synergy with -260C>T CD14 SNP on the outcome from critical conditions. We monitored 524 critically ill patients from South Brazilian, daily from the ICU admission to their discharge from hospital, or death. Our results revealed that TLR2, TLR4 or TNF-α SNPs alone did not show a significant role in the outcome from critical illness. However, when we performed a combined analysis with the CD14 inheritance, we detected a significant higher survivor rate in -260TT CD14/-308GG TNF-α individuals (P = 0.037). In the adjusted analysis including the main clinical predictors to mortality, we observed that -260TT/-308GG double-genotype was a significant protective factor towards survival (P = 0.046). An increased probability for survival of -260TT/-308GG was also observed by 'pathway genetic load' analysis (unweighted: P = 0.041; weighted: P = 0.036). When we applied a hazard function analysis with the -260TT/-308GG variable as a discriminating factor, -260TT/-308GG patients group had, in fact, a higher survivor rate (P = 0.024). Connected to the beneficial effect of -260TT CD14, the -308GG TNF-α genotype was protective against the reported over expression of TNF-α caused by -308A rare allele. Results support the hypothesis that the interaction between -260C>T CD14 and -308G>A TNF-α functional SNPs may be synergistically influencing the outcome of critically ill patients.

Lack of association of the CD14/C -- 159T polymorphism with susceptibility and progression parameters in Turkish multiple sclerosis patients

Soluble (s) CD14, being a receptor for lipopolysaccharides (LPSs) may inhibit LPS-triggered apoptosis and T lymphocyte proliferation. C to T exchange at position -159 in the promoter region of the CD14 gene might lead to higher sCD14 levels. Limited number of groups have studied whether these polymorphisms might influence the development of organ specific autoimmunity and whether higher CD14 levels are associated with increased levels of cytokines trigerring inflammatory processes. However their data contradict each other. In this study serum levels of sCD14 based on ELISA were measured in 77 treatment-naive patients and in 67 healthy controls. As the C-159T proximal promoter region regulates sCD14 levels, we investigated whether C-159T polymorphism is related to progression index in 250 MS patients vs. 183 healthy controls. CD14 polymorphism frequency between the healthy controls and the MS patients were not significantly different. While TT genotype of MS patients demonstrated significantly lower sCD14 levels compared to CC genotype; this difference was not reflected on the disease progression index. Our study that extends the prior data of previous studies reflects that sCD14 do not appear to be a solely prominent element of innate immunity in MS.

Genetic predisposition to respiratory infection and sepsis

Genetic variations, in part, determine individual susceptibility to sepsis and pneumonia. Advances in genetic sequence analysis as well as high throughput platform analysis of gene expression has allowed for a better understanding of immunopathogenesis during sepsis. Differences in genes can also modulate immune and inflammatory response during sepsis thereby translating to differences in clinical outcomes. An increasing number of candidate genes have been implicated to play a role in sepsis susceptibility, most of which are controversial with few exceptions. This does not refute the significance of genetic polymorphisms in sepsis, but rather highlights the difficulties and pitfalls related to genetic association studies. These difficulties include differences in study design such as heterogeneous patient cohorts and differences in pathogenic organisms, linkage disequilibrium, and lack of power for detailed haplotype analysis or examination of gene-gene interactions. There is extensive diversity in the pathways of inflammation and immune response during sepsis making it even harder to prove the functional and clinical significance of one single genetic polymorphism which could be easily masqueraded or compensated by other upstream or downstream events of the pathway involved. The majority of studies have analysed candidate genes in isolation from other possible polymorphisms. It is likely that susceptibility to sepsis is the result of polymorphisms from multiple genes rather than one single mutation. Future studies should aim for multi-centered collaborative approach looking at genome wide association or gene profiling to provide a more complete appraisal of the key genetic players in determining genetic susceptibility to sepsis. This review paper will summarise the prominent candidate gene polymorphisms with known functional changes or those with haplotype data. In addition, a summary of the expanding research in the field of epigenetics and post-sepsis immunosuppression will be discussed.

Association between toll-like receptors/CD14 gene polymorphisms and inflammatory bowel disease in Korean population

The innate immune response in patients who develop inflammatory bowel disease (IBD) may be abnormal. However, the exact role of Toll-like receptors (TLRs) / CD14 gene in the pathogenesis of IBD has not been fully elucidated. We aimed to investigate the association between polymorphisms of TLR1, 2, 4, 6, and CD14 gene and susceptibility to IBD in Korean population. A total 144 patients of IBD (99 patients with ulcerative colitis, 45 patients with Crohn's disease) and 178 healthy controls were enrolled. Using a PCR-RFLP, we evaluated mutations of TLR1 (Arg80Thr), TLR2 (Arg753Gln and Arg677Trp), TLR4 (Asp299Gly and Thr399Ile), TLR6 (Ser249Pro) genes and the -159 C/T promoter polymorphism of CD14 gene. No TLR polymorphisms were detected in Korean subjects. T allele and TT genotype frequencies of CD14 gene were significantly higher in IBD patients than in healthy controls. In subgroup analysis, T allelic frequency was higher in pancolitis phenotype of ulcerative colitis. In Korean population, the promoter polymorphism at -159 C/T of the CD14 gene is positively associated with IBD, both ulcerative colitis and Crohn's disease.

Macrophage migration inhibitory factor, Toll-like receptor 4, and CD14 polymorphisms with altered expression levels in patients with ulcerative colitis

Ulcerative colitis is a multifactorial disease in which genetic factors play a major role. Functional mutations in the genes related to innate immune response exacerbate mucosal damage coupled with persistent inflammation. The cytokine macrophage migration inhibitory factor (MIF), CD14, and Toll-like receptor 4 (TLR4) are the central players with clearly defined roles in inflammation. The aim of this study was to investigate the association between MIF-173G > C, CD14-159C > T, and TLR4-299A > G polymorphisms and mononuclear cell expression in patients with ulcerative colitis (UC). Genotyping of MIF-173G > C, CD14-159C > T, and TLR4-299A > G polymorphisms was performed by amplification refractory mutation system-polymerase chain reaction and allele-specific amplification in 139 and 176 patients with UC and controls, respectively. Simultaneously, the expression levels of intracellular MIF, mCD14, and mTLR4 were determined in mononuclear cells using a flow cytometer. Polymorphisms in CD14-159C > T and TLR4-299A > G significantly affected mCD14 and mTLR4 expression levels and also increased susceptibility to UC. Although intracellular MIF expression levels differed among patient and control groups, the polymorphism in MIF 173G > C was not observed to be associated with a risk of UC.

Gene polymorphisms contributing to hypertension in immunoglobulin A nephropathy

BACKGROUND

Hypertension, which is affected by genetic and environmental factors, is one of the major risk factors for chronic kidney disease. Identification of the genetic factor contributing to hypertension in patients with chronic kidney disease may potentially refine a therapeutic strategy.

METHODS

In the present multicenter cross-sectional study, 240 patients were eligible (aged 15-50 years with urinary protein ≥0.25 g/day) out of 429 patients who were diagnosed as having immunoglobulin (Ig) A nephropathy (IgAN) by renal biopsy between 1990 and 2005 and enrolled in our previous study, PREDICT-IgAN. The outcome was hypertension defined as ≥140 and/or ≥90 mmHg of systolic and diastolic blood pressure and/or use of antihypertensives at renal biopsy. We assessed associations between hypertension and 28 polymorphisms with the frequency of minor genotype ≥10% among 100 atherosclerosis-related polymorphisms using the Chi-squared test in dominant and recessive models. We identified polymorphisms associated with hypertension in multivariate logistic regression models.

RESULTS

Baseline characteristics: hypertension 36.3%. Among 28 polymorphisms, the Chi-squared test revealed that CD14 (-159CC vs CT/TT, P = 0.03) and ACE (DD vs DI/II, P = 0.03) were significantly associated with hypertension after Bonferroni correction. Multivariate logistic regression models revealed that CD14 -159CC [vs CT/TT, odds ratio (OR) 3.58 (95% confidence interval (CI) 1.66-7.63)] and ACE DD [vs DI/II, OR 4.41 (95% CI 1.80-10.8), P = 0.001] were independently associated with hypertension.

CONCLUSIONS

CD14 C-159T and ACE I/D contributed to hypertension in patients with IgAN.

CD14 (C-260T) polymorphism is not associated with sudden infant death syndrome (SIDS) in a large South Australian cohort

Similarities have been drawn between models of endotoxic shock and gross and microscopic pathology observed in sudden infant death syndrome (SIDS) cases. Polymorphisms in genes that influence the expression of endotoxin receptors could affect the outcome of toxaemia, and could, therefore, play a role in SIDS. The CD14 gene promoter contains a single nucleotide polymorphism that affects the level of CD14 gene expression. The TT genotype of the CD14 (C-260T) polymorphism causes a significantly higher density of CD14 receptor expression on monocytes which makes the individual more sensitive to endotoxin than those with the wild-type (CC). This investigation was designed to determine whether SIDS infants have a higher frequency of the CD14 (C-260T) polymorphism compared with non-SIDS controls. One hundred and sixteen SIDS and 228 control infants were genotyped using PCR followed by restriction fragment length analysis of amplified product. Carriage of the TT or CT genotypes did not significantly differ between SIDS and control infants (P = 0.218 and 0.081, respectively). The frequencies observed in the control group were consistent with Hardy-Weinberg equilibrium and did not differ significantly from the published frequencies in Caucasian Australians. These results suggest that CD14 (C-260T) polymorphism is unlikely to be implicated in SIDS.

Association between lymphotoxin-alpha (tumor necrosis factor-beta) intron polymorphism and predisposition to severe sepsis is modified by gender and age

OBJECTIVE

To investigate the significance of functional polymorphisms of inflammatory response genes by analysis of a large population of patients, both with and without severe sepsis, and representative of the diverse populations (geographic diversity, physician diversity, clinical treatment diversity) that would be encountered in critical care clinical practice.

DESIGN

: Collaborative case-control study conducted from July 2001 to December 2005.

SETTING

A heterogeneous population of patients from 12 U.S. intensive care units represented by the Genetic Predisposition to Severe Sepsis archive.

PATIENTS

A total of 854 patients with severe sepsis and an equal number of mortality, age, gender, and race-matched patients also admitted to the intensive care unit without evidence of any infection (matched nonseptic controls).

MEASUREMENTS AND MAIN RESULTS

We developed assays for six functional single nucleotide polymorphisms present before the first codon of tumor necrosis factor at -308, IL1B at -511, IL6 at -174, IL10 at -819, and CD14 at -159, and in the first intron of LTA (also known as tumor necrosis factor-B) at +252 (LTA[+252]). The Project IMPACT critical care clinical database information management system developed by the Society of Critical Care Medicine and managed by Tri-Analytics and Cerner Corporation was utilized. Template-directed dye-terminator incorporation assay with fluorescence polarization detection was used as a high-throughput genotyping strategy. Fifty-three percent of the patients were male with 87.3% and 6.4% of Caucasian and African American racial types, respectively. Overall mortality was 35.1% in both severe sepsis and matched nonseptic control patients group. Average ages (standard deviation) of the severe sepsis and matched nonseptic control patients were 63.0 (16.05) and 65.0 (15.58) yrs old, respectively. Among the six single nucleotide polymorphisms, LTA (+252) was most overrepresented in the septic patient group (% severe sepsis; AA 45.6: AG 51.1: GG 56.7, p = .005). Furthermore, the genetic risk effect was most pronounced in males, age >60 yrs (p = .005).

CONCLUSIONS

LTA(+252) may influence predisposition to severe sepsis, a predisposition that is modulated by gender and age. Although the genetic influences can be overwhelmed by both comorbid factors and acute illness in individual cases, population studies suggest that this is an influential biological pathway modulating risk of critical illnesses.

Impact of genetic variants of CD14 and TLR4 on subgingival periodontopathogens

CD14 and toll-like receptor 4 (TLR4) are involved in host's immune response to bacterial pathogens including periodontal bacteria. Functional important gene polymorphisms are described for both genes. The aim of this study was to evaluate links between genetic polymorphisms of CD14 and TLR4 and risk markers of periodontitis in a multivariate model. One hundred and thirty-three periodontitis patients (chronic: n = 60, aggressive: n = 73) and 80 healthy controls without periodontitis were included in the study. Polymorphisms in CD14 c.-159C>T and in TLR4 Asp299Gly, Thr399Ile were determined by restriction fragment length polymorphism analyses. The clinical investigation included smoking status, plaque and bleeding indexes, pocket depth and attachment loss. Subgingival bacterial colonization was analysed molecularbiologically using the micro-Ident test. Prevotella intermedia occurred less frequently in individuals positive for the TT genotype of CD14 in bivariate analysis (odds ratio = 0.36%, confidence interval: 0.14-0.91, P = 0.045). In binary logistic regression analyses, the occurrence of this bacterium was significantly decreased in TT carriers (odds ratio = 0.31%, confidence interval: 0.81-0.12, P = 0.017) considering age, smoking and maximum clinical attachment loss at microbial test site as confounding factors. However, no significant association with chronic and or aggressive periodontitis and polymorphisms in CD14 and TLR4 could be proven. Although the CD14 c.-159C>T polymorphism could be shown to be associated with subgingival colonization with P. intermedia, there is no evidence that CD14 and TLR4 polymorphisms investigated are independent risk factors for chronic or aggressive periodontitis in German periodontitis patients.

CD14 expression in the first 24h of sepsis: effect of -260C>T CD14 SNP

Sepsis is defined as systemic inflammation caused by infection. The membrane bound CD14 (mCD14) or the soluble form (sCD14) play a crucial role facing Gram-negative and Gram-positive sepsis since they are pattern recognition receptors of the innate immune response enabling cells to produce inflammatory cytokines against bacterial infections. A -260C>T single nucleotide polymorphism (SNP) was detected in the promoter modulating the CD14 gene expression. We hypothesized that the CD14 expression depends of the genetic inheritance of -260C>T CD14 SNP and it is modulated by sepsis condition. We investigated human CD14 expression on early sepsis diagnosis (in vivo) and after LPS stimulation (in vitro), and determined the -260C>T CD14 SNP. We found that TT homozygotes showed higher mCD14 density (p = 0.0207), but not different sCD14 levels when compared to the CT+CC genotypes. Monocyte mCD14 density and sCD14 serum levels in our sample of early 14 septic patients were significantly higher than normal 30 controls (p<0.0001). Our results suggest that the -260TT CD14 genotype is associated with higher monocyte mCD14, but not sCD14 expression, and that in the first 24 h after sepsis diagnosis, both monocyte mCD14 density and sCD14 levels are elevated, similarly to what is observed in vitro upon challenge with LPS.

159C>T CD14 genotype--functional effects on innate immune responses in term neonates

Given the susceptibility of newborns to infection and the potential harm of overwhelming proinflammatory immune responses, the impact of genetic variation in innate immune molecules is of increasing interest for risk stratification and prevention. We studied the functional relevance of the 159C>T CD14 single nucleotide polymorphism in cord blood samples of n=135 healthy term neonates by investigation of sCD14, interleukin (IL)-6, IL-10, and tumor necrosis factor (TNF)-alpha concentrations in whole-blood culture supernatants and intracellular assessment of IL-1beta, IL-6, and TNF-alpha expression by flow cytometry. The 159C>T CD14 genotype frequencies were n=42 (0.31) for homozygous CD14-159 CC, n=69 (0.51) for heterozygous CD14-159 CT, and n=24 (0.18) for homozygous CD14-159 TT. No genotype-associated differences were noted for ex vivo baseline expression of sCD14, IL-6, IL-10, and TNF-alpha. After in vitro stimulation of cord blood cultures with lipopolysaccharide, carriers of the CD14-159 T allele were determined to have higher levels of sCD14 compared with carriers of the CD14-159 C allele (p=0.04) and increased concentrations of IL-6 (p=0.009) in culture supernatants (one-way analysis of variance). The 159C>T CD14 polymorphism is associated with soluble CD14 expression and cytokine expression, which might influence the balance of pro- and anti-inflammatory immune responses in healthy term neonates. Further studies are needed to delineate whether the 159C>T CD14 genotype is a risk factor for severity of neonatal infection in the clinical setting and a potential target for prevention strategies.

Molecular and cellular aspects of sepsis-induced immunosuppression

Sepsis is a significant cause of death worldwide. Although the prevailing theory of the sepsis syndrome has been that of a condition of uncontrolled inflammation in response to infection, sepsis is increasingly being recognized as an immunosuppressive state. The immune modulations of sepsis result in altered innate and adaptive immune responses, thereby rendering the septic host susceptible to secondary infections. In this review, we present an overview of the clinical and experimental evidence for sepsis-induced immunosuppression and outline the mechanisms that underlie this phenotype. With an improved understanding of how host immune states may be altered during sepsis, better immunomodulatory therapies may be developed to address the immune derangements observed in patients with sepsis.