CD14 Single Nucleotide Polymorphisms Research Articles

TLR Signaling Pathway Gene Polymorphisms, Gene-Gene and Gene-Environment Interactions in Allergic Rhinitis.

ABSTRACTBackgroundAllergic rhinitis (AR) is a nasal inflammatory disease resulting from a complex interplay between genetic and environmental factors. The association between Toll-like receptor (TLR) signaling pathway and environmental factors in AR pathogenesis remains to be explored. This study aims to assess the genetic association of AR with single nucleotide polymorphisms (SNPs) in TLR signaling pathway, and investigate the roles of gene–gene and gene–environment interactions in AR.MethodsA total of 452 AR patients and 495 healthy controls from eastern China were enrolled in this hospital-based case–control study. We evaluated putatively functional genetic polymorphisms in TLR2, TLR4 and CD14 genes for their association with susceptibility to AR and related clinical phenotypes. Interactions between environmental factors (such as traffic pollution, residence, pet keeping) and polymorphisms with AR were examined using logistic regression. Models were stratified by genotype and interaction terms, and tested for the significance of gene–gene and gene–environment interactions.ResultsIn the single-locus analysis, two SNPs in CD14, rs2563298 (A/C) and rs2569191 (C/T) were associated with a significantly decreased risk of AR. Compared with the GG genotype, the GT and GT/TT genotypes of TLR2 rs7656411 (G/T) were associated with a significantly increased risk of AR. Gene–gene interactions (eg, TLR2 rs7656411, TLR4 rs1927914, and CD14 rs2563298) was associated with AR. Gene–environment interactions (eg, TLR4 or CD14 polymorphisms and certain environmental exposures) were found in AR cases, but they were not significant after Bonferroni correction.ConclusionThe genetic polymorphisms of TLR2 and CD14 and gene–gene interactions in TLR signaling pathway were associated with susceptibility to AR in this Han Chinese population. However, the present results were limited to support the association between gene–environment interactions and AR.

CD33 rs2455069 SNP: Correlation with Alzheimer's Disease and Hypothesis of Functional Role.

The CD33 gene encodes for a member of the sialic-acid-binding immunoglobulin-type lectin (Siglec) family, and is one of the top-ranked Alzheimer’s disease (AD) risk genes identified by genome-wide association studies (GWAS). Many CD33 polymorphisms are associated with an increased risk of AD, but the function and potential mechanism of many CD33 single-nucleotide polymorphisms (SNPs) in promoting AD have yet to be elucidated. We recently identified the CD33 SNP rs2455069-A>G (R69G) in a familial form of dementia. Here, we demonstrate an association between the G allele of the rs2455069 gene variant and the presence of AD in a cohort of 195 patients from southern Italy. We carried out in silico analysis of the 3D structures of CD33 carrying the identified SNP to provide insights into its functional effect. Structural models of the CD33 variant carrying the R69G amino acid change were compared to the CD33 wild type, and used for the docking analysis using sialic acid as the ligand. Our analysis demonstrated that the CD33-R69G variant may bind sialic acid at additional binding sites compared to the wild type, thus potentially increasing its affinity/specificity for this molecule. Our results led to a new hypothesis of rs2455069-A>G SNP as a risk factor for AD, suggesting that a long-term cumulative effect of the CD33-R69G variant results from the binding of sialic acid, acting as an enhancer of the CD33 inhibitory effects on amyloid plaque degradation.

The influence of single nucleotide polymorphisms of NOD2 or CD14 on the risk of Mycobacterium tuberculosis diseases: a systematic review

BackgroundTuberculosis (TB) is still one of the leading causes of death worldwide. Genetic studies have pointed to the relevance of the NOD2 and CD14 polymorphic alleles in association with the risk of diseases caused by Mycobacterium tuberculosis (Mtb) infection.MethodsA systematic review was performed on PubMed, EMBASE, Scientific Electronic Library Online (SciELO), and Literatura Latino-Americana e do Caribe em Ciências da Saúde (Lilacs) to examine the association between single nucleotide polymorphisms (SNP) and risk of Mtb diseases. Study quality was evaluated using the Newcastle-Ottawa Quality Scale (NOQS), and the linkage disequilibrium was calculated for all SNPs using a webtool (Package LDpop).ResultsThirteen studies matched the selection criteria. Of those, 9 investigated CD14 SNPs, and 6 reported a significant association between the T allele and TT genotypes of the rs2569190 SNP and increased risk of Mtb diseases. The genotype CC was found to be protective against TB disease. Furthermore, in two studies, the CD14 rs2569191 SNP with the G allele was significantly associated with increased risk of Mtb diseases. Four studies reported data uncovering the relationship between NOD2 SNPs and risk of Mtb diseases, with two reporting significant associations of rs1861759 and rs7194886 and higher risk of Mtb diseases in a Chinese Han population. Paradoxically, minor allele carriers (CG or GG) of rs2066842 and rs2066844 NOD2 SNPs were associated with lower risk of Mtb diseases in African Americans.ConclusionsThe CD14 rs2569190 and rs2569191 polymorphisms may influence risk of Mtb diseases depending on the allele. Furthermore, there is significant association between NOD2 SNPs rs1861759 and rs7194886 and augmented risk of Mtb diseases, especially in persons of Chinese ethnicity. The referred polymorphisms of CD14 and NOD2 genes likely play an important role in risk of Mtb diseases and pathology and may be affected by ethnicity.Systematic review registrationCRD42020186523

Precision Medicine in Graves' Disease: CD40 Gene Variants Predict Clinical Response to an Anti-CD40 Monoclonal Antibody.

BackgroundCD40, a key co-stimulatory molecule expressed on antigen-presenting cells, is genetically associated with a number of autoimmune diseases including Graves’ disease (GD). Therefore, recent therapies targeting CD40 have been developed, including the anti-CD40 monoclonal antibody Iscalimab. In a recent pilot study, Iscalimab was shown to induce clinical remission in ~ 50% of GD patients, but the reason why only 50% of GD patients responded is not known. The aim of our study was to test the hypothesis that specific CD40 single nucleotide polymorphism (SNP) genotypes and haplotypes are associated with clinical response of GD patients to Iscalimab.MethodsWe extracted genomic DNA from the whole blood of 13 GD patients treated with Iscalimab, and genotyped seven CD40 single nucleotide polymorphisms (SNPs) associated with autoimmunity. Additionally, we analyzed CD40 mRNA expression levels in whole blood. The patients’ CD40 SNP genotypes and mRNA levels were tested for association with clinical response to Iscalimab.ResultsThree common haplotypes, designated haplotypes A, B, and C, were identified. Haplotypes B and C were associated with higher CD40 mRNA levels and clinical response to Iscalimab (i.e., patients achieving euthyroidism without need for additional medications), while haplotype A was associated with decreased CD40 mRNA levels and no response to Iscalimab.ConclusionOur data suggest that genetic polymorphisms in the CD40 gene drive its expression levels and response to Iscalimab. Polymorphisms associated with higher CD40 levels are also associated with clinical response to CD40-targeted therapies. These results set the stage to implementing precision medicine in the therapeutic approach to GD.

CD14 Gene (−159 C>T) Polymorphism and its Surface Expression on Monocytes in Pulmonary Tuberculosis Patients

BACKGROUND: Tuberculosis (TB) is an infectious disease that affects millions of people around the world. The innate immune response against TB starts by interaction of several receptors on monocytes with mycobacterium tuberculosis (MTB). CD14 is one of these receptors present on the monocytes which facilitate the entry of MTB into the cell. Certain polymorphisms in CD14 gene, for example, CD14 (−159 C>T) in the promotor region have suggested susceptibility of TB.
 AIM: This study was designed to determine and compare CD14 (−159 C>T) gene polymorphism and its surface expression in pulmonary TB patients (before and during anti-TB treatment) and healthy controls.
 MATERIALS AND METHODS: The study population comprised three groups (pulmonary TB patients before treatment, pulmonary TB patients during treatment, and healthy controls) whereas 53 blood samples were collected from each group. The percentage of monocytes and CD14 mean fluorescence intensity (MFI) was measured by flow cytometry whereas polymerase chain reaction-restriction fragment length polymorphism was used to determine gene polymorphism.
 RESULTS: CD14 MFI was significantly high in healthy controls than in TB patients (432 as compared to 193 and 365, p < 0.0001). There was no significant difference in CD14 single nucleotide polymorphism allele frequencies or genotypes between TB patients and healthy controls.
 CONCLUSION: CD14 gene (−159 C>T) polymorphism was not associated with pulmonary TB disease in a sample of Pakistani population and surface expression of CD14 receptor on peripheral blood monocytes decreases with active TB disease and during treatment.

Functional association of a CD40 gene single-nucleotide polymorphism with the pathogenesis of coronary heart disease.

Endothelial dysfunction is a major contributor to the pathogenesis of atherosclerosis. CD40-CD40 ligand interactions confer a pro-inflammatory phenotype to endothelial cells (ECs). Recently, a thymine to cytosine transition (-1T>C) in the Kozak sequence of the CD40 gene (rs1883832) has been associated with coronary heart disease (CHD) in an Asian population. As there are no reports yet regarding its role in other ethnic groups, this study determines if the -1T>C single-nucleotide polymorphism (SNP) could be a risk factor for CHD in Caucasians by performing an association study and elucidates its functional consequence in cultured ECs. Molecular and biochemical techniques, cell adhesion assays were used for genotype-stratified human EC characterization. SNP distribution in Caucasians was examined in a hospital-based case-control CHD study and serum levels of soluble CD40 (sCD40) were quantified by ELISA. The SNP in the CD40 gene affected baseline CD40 protein abundance on ECs. There was a genotype-dependent difference in CD40-mediated expression of pro-inflammatory genes. Monocyte adhesion was highest on the surface of cells homozygous for the C allele. Homozygosity for the C allele was associated with significant 2.32-fold higher odds of developing CHD as compared to TT genotype carriers. sCD40 plasma levels were genotype-dependently elevated in CHD patients, indicating a possible prognostic value. The C allele of the CD40 SNP provokes a pro-inflammatory EC phenotype, compensated by an enhanced CD40 shedding to neutralize excess CD40 ligand. Homozygosity for the C allele is the cause for a genetic susceptibility to atherosclerosis and its sequelae.

PB1722 IMPACT OF CD33 AND ABCB1 SINGLE NUCLEOTIDE POLYMORPHISMS IN PATIENTS WITH ACUTE MYELOID LEUKEMIA AND HIGH‐RISK MYELODYSPLASTIC SYNDROMES TREATED WITH DECITABINE PLUS GEMTUZUMAB OZOGAMICIN

Background:Single nucleotide polymorphisms (SNPs) of CD33 are predictive for relapse risk in children with acute myeloid leukemia (AML) receiving gemtuzumab ozogamicin (GO)‐containing regimens. However, the impact of CD33 SNPs on response to GO is controversial in adults. To our knowledge, no study has evaluated whether SNPs of CD33 or ABCB1, a protein that mediates GO resistance in pre‐clinical studies, predict for outcomes in patients (pts) with AML or high‐risk myelodysplastic syndromes (MDS) receiving low‐intensity therapy in combination with GO.Aims:To evaluate the impact of CD33 expression and of CD33 and ABCB1 SNPs on response, risk of relapse, and survival in pts with AML or high‐risk MDS or myelofibrosis treated in a prospective clinical trial with decitabine plus GO.Methods:Pts received decitabine 20 mg/m2 daily x 5 days plus GO 3 mg/m2 on day 5, followed by up to 5 consolidation cycles of decitabine plus GO, then decitabine alone (Daver et al. Leukemia 2016;30[2]:268‐73). Genotyping of the following SNPs was performed and correlated with clinical outcomes: ABCB1 rs1128503, ABCB1 rs1045642, CD33 rs2455069, CD33 rs35112940, CD33 rs12459419, CD33 rs1803254, CD33 rs61736475, and CD33 rs201074739. An aggregate “6 CD33 SNP score” was determined based on genotypes of the 6 CD33 SNPs, as previously described (Lamba J et al. ASH 2017, abstract 3826).Results:113 pts were treated with decitabine plus GO, 104 of whom underwent CD33 and ABCB1 SNP genotyping. Baseline characteristics of the population is shown in Table 1. For the entire cohort, 36 pts (32%) achieved any response (ORR, i.e. CR + CRi + MLFS), 16 of whom (14%) achieved CR. ORR was 47% and 18%, and CR rate was 23% and 7% for the frontline and relapsed/refractory cohorts, respectively. With a median follow‐up of 107 months, median RFS and OS were 4.8 and 10.0 months in the frontline, and 3.0 and 6.6 months in the relapsed/refractory cohorts, respectively. For the whole cohort, CD33 median fluorescence intensity (MFI) was not significantly associated with ORR, but was associated with CR (OR 1.02; P = 0.02). No individual CD33 or ABCB1 SNP was predictive for ORR or CR; however, among pts with 6 CD33 SNP score ≥0, there was a trend towards higher CR rate (21% vs. 8%, OR 3.08; P = 0.07), but not with ORR (P = 0.94). Neither CD33 MFI nor any individual genotype or the 6 CD33 SNP score were significantly associated with cumulative incidence of relapse (CIR), relapse‐free survival (RFS) or overall survival (OS). In the subgroup of pts with AML (n=91), CD33 MFI was not significantly associated with ORR, but was associated with CR (OR 1.02; P = 0.02). The GG genotype of CD33 rs1803254 (n=67) was associated with lower CIR and better RFS than the CC/CG genotypes (n=15) in the AML cohort (median RFS 5.1 versus 2.5 months, P = 0.02), although this was driven by only 3 pts with the CC/CG genotypes who responded and included in RFS analysis; there was no association with OS. No other SNP, nor the 6 CD33 SNP score, was significantly associated with CR, ORR, CIR, RFS or OS in any subgroup analyses.Summary/Conclusion:In this poor‐risk cohort of pts with MDS or AML treated with decitabine plus GO, neither CD33 MFI nor ABCB1 or CD33 SNPs were meaningfully predictive for outcomes; however, this cohort was heterogeneous and the overall efficacy of this regimen was low, which may have obscured any potential predictive value of these SNPs. Evaluation of these SNPs in pts treated with more effective low intensity regimens (e.g. hypomethylating agent plus venetoclax) in combination with GO is warranted.image

Enhancement of Eligibility Guidelines for Gemtuzumab Ozogamicin Therapy for Childhood Acute Myeloid Leukemia: A Report from Children's Oncology Group Protocol AAML0531

Background: CD33 is variably expressed on leukemia blasts in most patients with acute myeloid leukemia (AML). Efforts to target CD33 therapeutically have focused on gemtuzumab ozogamicin (GO), an antibody-drug conjugate delivering a DNA-damaging calicheamicin derivative. Qualification for GO therapy has been determined by expression of CD33 by multidimensional flow cytometry (MDF); patients with positive CD33 expression receive GO. Previous studies from the AAML0531 protocol demonstrated that the cell surface intensity expression of CD33, determined by MDF, predicts the response to treatment with GO, and that in part this expression is regulated by a pair of CD33 single nucleotide polymorphisms (SNPs) in linkage disequilibrium that also, independently, predict response to therapy. Patients with CC genotype for rs12459419 have lower relapse risk and improved disease-free survival, compared to CT and TT genotypes. Because GO therapy is associated with treatment-related toxicity, it is important to identify biologic variables associated with benefits and risks. To date, there has been no report associating SNP status among CD33 positive versus CD33 negative patients that could assess how the combination of these biomarkers for determining administration of GO therapy could improve patient outcomes.Objective: In an effort to determine which children would benefit most from GO treatment in future prospective pediatric AML protocols, we aimed to elucidate if CD33 SNP genotype status should be combined with quantitative CD33 cell surface antigen expression on the diagnostic leukemia cells (CD33+ versus CD33-) to determine GO eligibility, with a retrospective analysis of children enrolled in Children's Oncology Group AAML0531.Methods: Of 1022 newly diagnosed pediatric patients with de novo AML enrolled on protocol AAML0531, 666 satisfied two criteria for this study: (1) submission of a blood or bone marrow sample for MDF at diagnosis with corresponding CD33 SNP genotype data available, and (2) proper consent for specimen testing.CD33 Expression Levels on Leukemic BlastsThe diagnostic AML leukemia population was identified by gating on CD45 versus log-side scatter and CD33 expression levels were determined by measuring the mean fluorescence intensity (MFI) by flow cytometry. For a patient to be considered CD33+ two criteria were required: intensity of CD33 on blasts was at minimum four times the MFI of its correspondent autofluorescent control, and at least 80% of the total blasts were greater than this minimum.Genotyping CD33 SNPsCD33-coding SNP rs12459419-Ala14Val and linked promoter SNP rs3865444 were genotyped using the Sequenome (San Diego, CA) platform at the Biomedical Genomics Center, University of Minnesota. Both SNPs had a call rate of 0.98 and were in Hardy-Weinberg equilibrium (P=0.05).Results:Association of Genotype and cell surface expression of CD33 for AAML0531 patients Of 666 patients, 84% (560/666) were CD33+. CC genotype was observed in 54.5% (305/560) of CD33+ cases, 37.5% (210/560) had CT genotype and 8% (45/560) TT genotype. Of the 16% (106/666) of patients who were CD33 negative, 33% (35/106) had CC genotype, 47% (50/106) CT genotype, and 20% (21/106) had TT genotype. Comprehensively, 340/666 (51%) had CC genotype (51%) and 10% were CD33 negative (35/340). Conversely, out of a total of 66 patients with TT genotype, 45 (68%) were CD33+ and 32% (21/66) were CD33 negative.Conclusions: These results clarify the relationship between the amount of CD33 expressed on AML at diagnosis as measured by MDF and CD33 SNP genotype status. While correlation with clinical outcome analysis is ongoing, these data support inclusion of CD33 SNP genotyping for eligibility of GO therapy. Therefore, the current recommendation for future COG AML clinical protocols is that GO will be administered to patients with CD33 expression as determined by MDF and CC genotype patients regardless of CD33 expression. DisclosuresPardo:Hematologics, Inc: Employment. Eidenschink Brodersen:Hematologics, Inc: Employment. Paine:Hematologics, Inc: Employment. Loken:Hematologics, Inc: Employment, Equity Ownership.

1866P - Association of the rs1883832 variant of CD40 with NSCLC risk and overall survival

Background: During the last few years a growing number of studies has attempted to shed light on the role of CD40 (Tumor Necrosis Factor Receptor Superfamily Member 5) in non-small-cell lung cancer (NSCLC), which remains the leading cause of cancer-related deaths worldwide. The aim of the current study was to investigate the clinical relevance of CD40 functional single nucleotide polymorphism (SNP) rs1883832 (-1C/T) with susceptibility to NSCLC, the clinicopathological parameters, relapse and survival rates of NSCLC patients, as well as with the protein expression of CD40. Methods: CD40 SNP rs1883832 was genotyped in 268 randomly selected NSCLC patients and 279 age- and gender-matched healthy donors. Patients were under observation during a five-year period. Immunohistochemical analysis for CD40 was performed on 106 NSCLC tumor tissue samples. All the participants were Greeks with Caucasian origin. Results: Genotype frequencies of rs1883832 (CC, CT, and TT) were significantly different between healthy controls and patients. CC homozygotes had higher risk for NSCLC compared to T allele carriers in univariate (P < 0.001), as well as in multivariate analysis (P = 0.006). In addition, rs1883832 was related to overall survival. More specifically, CT heterozygotes had worse clinical outcome after two-, three- and five-year observation compared to TT and CC homozygotes (P = 0.015, P = 0.005 and P = 0.017, respectively). Stratifying according to histological subtype, this association was observed only in patients with adenocarcinomas (P = 0.028) and not in patients with squamous- and large-cell carcinomas. Furthermore, taking into consideration disease stage, worse survival for CT heterozygotes was observed in stage II patients and not in patients of other stages (P = 0.016). Moreover, the variant had also strong association with brain metastases, with T allele carriers developing more often metastatic disease in CNS (P = 0.018). Interestingly, rs1883832 was related to CD40 protein expression in malignant cells (P < 0.001) as well as in stromal cells (P = 0.004). Conclusions: The present findings suggest that investigated SNP rs1883832 may be a useful and independent biomarker in NSCLC. However, more studies are needed in order to further demonstrate their role in NSCLC. Legal entity responsible for the study: University of Patras. Funding: Has not received any funding. Disclosure: All authors have declared no conflicts of interest.

Single nucleotide polymorphisms of IL-13 and CD14 genes in allergic rhinitis: a meta-analysis.

The aim of this study was to conduct a meta-analysis for single nucleotide polymorphisms (SNPs) in interleukin-13 (IL-13) and cluster of differentiation 14 (CD14) genes and the risk for allergic rhinitis (AR). We screened studies identified through seven databases including Pubmed, Medline, Web of Science, Embase, China Biology Medicine disc, Wanfang, and China Academic Journal Network Publishing Database. The odds ratios (ORs) and 95% confidence intervals (CIs) were determined to assess the association under allelic, dominant and recessive models. Twelve studies with a total of 8547 participants (3223 cases and 5324 controls) investigated IL-13 SNP rs20541, five studies combining 4580 participants (1411 cases and 3169 controls) examined IL-13 SNP rs1800925, and nine studies with 2301 participants (1174 cases and 1127 controls) assessed CD14 SNP rs2569190. We found that the A allele of IL-13 SNP rs20541 was associated with an increased risk of AR (OR 1.19, 95% CI 1.11-1.28, P < 0.001). Stratifying studies by ethnic group produced significant results in Asians (OR 1.21, 95% CI 1.11-1.32, P < 0.001), but not in Caucasians (OR 1.14, 95% CI 1.00-1.30, P = 0.051). No association of IL-13 SNP rs1800925 and CD14 SNP rs2569190 with AR risk was found in either Asians or Caucasians (P > 0.05). Our findings suggest that IL-13 SNP rs20541 is significantly associated with AR risk in Asians but not in Caucasians. However, the accumulating evidence does not support an association of IL-13 SNP rs1800925 and CD14 SNP rs2569190 with AR risk.

SNPs of CD14 change the mastitis morbidity of Chinese Holstein.

Gram‑negative (GN) bacterial infection is a main cause of bovine mastitis. The cluster of differentiation (CD) 14 gene serves an essential role in GN bacterium‑induced innate immune response. CD14 works as a bacterial lipopolysaccharide (LPS) receptor, combines with LPS‑liposaccharide binding protein complex, and causes cellular activation. However, the effects of CD14 single nucleotide polymorphisms (SNPs) on morbidity of clinical mastitis remain unclear. In the present study, To investigate the polymorphisms of CD14 gene and its effects on cows' susceptibility to mastitis, polymerase chain reaction‑single‑strand conformation polymorphism (PCR‑SSCP) assay was used to detect SNPs of CD14 gene in 134 Chinese Holsteins. SNPs were identified in PCR products amplified with 3 sets of primers in CD14 exon 2. A total of three SNPs were located in that exon: g.528 A→C (147Ser→Arg) in allele B; g.612 A→G (175Asn→Asp) in allele D; and g.1022 A→G in allele F (synonymous mutation). The SNPs in alleles B and D affected the secondary structure of CD14. A 3‑dimensional (3D) structural analysis predicted three potential protein forms with a similar structure and indicated that the changes of the above‑mentioned alleles were on the concave surface of the protein. In more detail, 147 Ser→Arg induced a protein kinase C phosphorylation site to move forward, as assessed by the motif analysis. The morbidity rate of AB (mixed type g.528 A/C) and CD (mixed type g.612 A/G) was the highest among all genotypes presented in the current study, and via of tumor necrosis factor‑α and interleukin‑6 mRNA levels were upregulated in animals of this genotype compared with others. Taken together, the CD14 SNPs identified in the present study, may be closely associated with the morbidity of mastitis.

Single Nucleotide Polymorphisms in CD14 and Toll-like Receptor 4 Genes in Patients with Polycystic Ovarian Syndrome

ABSTRACT Introduction Polycystic ovary syndrome (PCOS) is a complex disease having genetic, immunologic, and environmental components, and candidate genes on innate immunity have been hypothesized to be involved in its etiology. We examined the possible association of CD14 and toll-like receptor 4 (TLR4) polymorphisms with PCOS. Materials and methods A total of 219 women with PCOS and 272 healthy women were recruited in the study. Their samples were genotyped for the polymorphism of CD14 and TLR4 genes. Results The distributions of genotypes of both polymorphisms were found to be significant in women with PCOS compared with controls. The distributions of alleles were also found to be predominant in PCOS compared with controls. Conclusion Polymorphisms in CD14-159C&gt;T and TLR4-299A&gt;G significantly increased susceptibility to PCOS. Further studies with larger sample sizes are warranted to confirm these findings. How to cite this article Allauddin N, Rozati R. Single Nucleotide Polymorphisms in CD14 and Toll-like Receptor 4 Genes in Patients with Polycystic Ovarian Syndrome. J South Asian Feder Obst Gynae 2017;9(4):304-307.

Polymorphisms in the CD14 and TLR4 genes independently predict CD4+ T-cell recovery in HIV-infected individuals on antiretroviral therapy.

Chronic HIV infection leads to marked depletion of CD4 T cells in the gastrointestinal tract and increased microbial translocation measured by an increase in circulating lipopolysaccharide (LPS) levels. Here, we hypothesized that single-nucleotide polymorphisms (SNPs) in genes encoding the Toll-like receptor 4 (TLR4) and CD14, the principal receptors for LPS, were associated with CD4 T-cell recovery postantiretroviral therapy (ART). Prospective study of predominantly white HIV-infected participants receiving suppressive ART for at least 12 months. We analysed the CD14 SNPs C-260T and the TLR4 SNPs A+896G, C+1196T. We also determined the levels of LPS and soluble CD14 in plasma samples collected pre-ART and post-ART initiation. CD4 T-cell recovery was assessed by linear mixed models. Following ART, individuals with a TT genotype compared with a CT or CC genotype for CD14 C-260T SNP showed higher levels of soluble CD14 (P = 0.008 and 0.003, respectively). The CC genotype for the CD14 C-260T SNP, compared with CT or TT, and the TLR4 SNP (AC/GT), compared with the homozygous genotype (AA/CC), were both independently associated with enhanced long-term CD4 T-cell recovery (>3 months; P < 0.001). Polymorphisms in CD14 and TLR4 are independently associated with long-term CD4 T-cell recovery in HIV-infected individuals post-ART.

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.

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.

Genetic variants in endotoxin signalling pathway, domestic endotoxin exposure and asthma exacerbations.

We investigated the interaction between genetic variants in endotoxin signalling pathway and domestic endotoxin exposure in relation to asthma presence, and amongst children with asthma, we explored the association of these genetic variants and endotoxin exposure with hospital admissions due to asthma exacerbations. In a case-control study, we analysed data from 824 children (417 asthmatics, 407 controls; age 5-18 yr). Amongst asthmatics, we extracted data on hospitalization for asthma exacerbation from medical records. Endotoxin exposure was measured in dust samples collected from homes. We included 26 single-nucleotide polymorphisms (SNPs) in the final analysis (5 CD14, 7LY96 and 14 TLR4). Two variants remained significantly associated with hospital admissions with asthma exacerbations after correction for multiple testing: for CD14 SNP rs5744455, carriers of T allele had decreased risk of repeated hospital admissions compared with homozygotes for C allele [OR (95% CI), 0.42 (0.25-0.88), p = 0.01, False Discovery Rate (FDR) p = 0.02]; for LY96 SNP rs17226566, C-allele carriers were at a lower risk of hospital admissions compared with T-allele homozygotes [0.59 (0.38-0.90), p = 0.01, FDR p = 0.04]. We observed two interactions between SNPs in CD14 and LY96 with environmental endotoxin exposure in relation to hospital admissions due to asthma exacerbation which remained significant after correction for multiple testing (CD14 SNPs rs2915863 and LY96 SNP rs17226566). Amongst children with asthma, genetic variants in CD14 and LY96 may increase the risk of hospital admissions with acute exacerbations. Polymorphisms in endotoxin pathway interact with domestic endotoxin exposure in further modification of the risk of hospitalization.

Toll-Like Receptor 4 and CD14 Gene Polymorphisms in Tunisian Kidney Transplantation

BackgroundAcute and chronic rejections remain an important cause of graft loss after renal transplantation. Currently, activation of innate immune responses through Toll-like receptors (TLRs) is suspected to be implied in the loss of the transplant tolerance. ObjectivesWe investigated functional single nucleotide polymorphisms (SNPs) of TLR4 and its coreceptor CD14 in kidney transplantation and looked for any potential role in acute rejection (AR) and chronic allograft nephropathy (CAN) and impact on graft survival. Patients and MethodsTLR4 (Asp299Gly) and CD14 (C/T -159) SNPs were detected using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in 209 kidney transplant recipients (KTRs) including 132 treated with mycophenolate mofetil (MMF+). AR occurred in 59 patients and 24 were identified as having CAN by biopsy and scored according to the Banff criteria. ResultsThere were no significant associations between TLR4 and CD14 genotypes and alleles and the occurrence of both AR episodes and CAN. Moreover, TLR4 and CD14 SNPs did not seem to influence kidney graft survival. Analysis according to human leukocyte antigen (HLA) compatibility status, positivity of anti-HLA antibodies, and immunosuppression by MMF confirmed the absence of correlation of the investigated SNPs with the graft outcome. In addition, incidence of post-transplantation infections, including cytomegalovirus (CMV) infections, was not influenced by both TLR4 and CD14 SNPs. ConclusionThese results suggest that TLR4 (Asp299Gly) and CD14 (C/T -159) functional SNPs do not play a major role in AR, CAN, and kidney graft survival. Therefore, intragraft monitoring of TLR4/CD14 genes expression by messenger RNA (mRNA) would provide clarity on the exact role of these receptors in graft injuries.

Polymorphisms of Helicobacter pylori signaling pathway genes and gastric cancer risk in the European prospective investigation into cancer‐eurgast cohort

Helicobacter pylori is a recognized causal factor of noncardia gastric cancer (GC). Lipopolysaccharide and peptidoglycan of this bacterium are recognized by CD14, TLR4 and NOD2 human proteins, while NFKB1 activates the transcription of pro‐inflammatory cytokines to elicit an immune response. Single nucleotide polymorphisms (SNPs) in these genes have been associated with GC in different populations. We genotyped 30 SNPs of these genes, in 365 gastric adenocarcinomas and 1,284 matched controls from the European Prospective Investigation into Cancer cohort. The association with GC and its histological and anatomical subtypes was analyzed by logistic regression and corrected for multiple comparisons. Using a log‐additive model, we found a significant association between SNPs in CD14, NOD2 and TLR4 with GC risk. However, after applying the multiple comparisons tests only the NOD2 region remained significant (p = 0.009). Analysis according to anatomical subtypes revealed NOD2 and NFKB1 SNPs associated with noncardia GC and CD14 SNPs associated with cardia GC, while analysis according to histological subtypes showed that CD14 was associated with intestinal but not diffuse GC. The multiple comparisons tests confirmed the association of NOD2 with noncardia GC (p = 0.0003) and CD14 with cardia GC (p = 0.01). Haplotype analysis was in agreement with single SNP results for NOD2 and CD14 genes. From these results, we conclude that genetic variation in NOD2 associates with noncardia GC while variation in CD14 is associated with cardia GC.

Racial differences in the association of CD14 polymorphisms with serum total IgE levels and allergen skin test reactivity

BackgroundThe CD14 C-159T single nucleotide polymorphism (SNP) has been investigated widely as a candidate genetic locus in patients with allergic disease. There are conflicting results for the association of the CD14 C-159T SNP with total serum immunoglobulin E (IgE) levels and atopy. There are limited data regarding the association of the CD14 C-159T SNP in subjects of African ancestry. The aim of the study was to determine whether the C-159T SNP and other CD14 SNPs (C1188G, C1341T) were associated with total serum IgE levels and with allergy skin test results in nonatopic and atopic subjects; as well as in Caucasian and African American subjects.MethodsA total of 291 participants, 18–40 years old, were screened to determine whether they were atopic and/or asthmatic. Analyses were performed to determine the association between CD14 C-159T, C1188G, or C1341T genotypes with serum IgE levels and with the number of positive skin tests among Caucasian or African American subjects.ResultsWe found no significant association of serum total IgE level with CD14 C-159T, C1188G, or C1341T genotypes within nonatopic or atopic subjects. Subjects with CD14-159 T alleles had significantly more positive allergen skin tests than subjects without CD14-159 T alleles (P = 0.0388). There was a significant association between the CD14 1188 G allele, but not the CD14 1341 T allele, with the number of positive skin-test results in Caucasians, but not in African Americans.ConclusionThese results support a possible association between CD14 polymorphisms and atopy. CD14-159 T or CD14 1188 G alleles were associated with atopic disease. For subjects with CD14 1188 G alleles, the association with atopic disease was stronger in Caucasians compared to African Americans.