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Ring, S.

Publications and source records attributed to Ring, S..

11 recordsLinked to original sources

B cell/adipocyte crosstalk drives pro-fibrotic macrophage migration and polarisation in Crohn`s disease-associated, inflamed adipose tissue

During Crohns disease (CD), hyperplasia of the mesenteric white adipose tissue (WAT), called creeping fat (CrF), is associated with the accumulation of immune cells. We here investigated whether B cell infiltration and their interaction with adipocytes influence inflammation and fibrosis of CD-associated adipose tissue. Analysing CrF of CD patients as well as WAT from a mouse model of intestinal inflammation, we found an accumulation of B cells and pro-fibrotic, M2-like macrophages. Depleting B cells through anti-CD20 antibody treatment diminished M2-like macrophage accumulation in inflamed mouse WAT. Mechanistically, we found that the B cell/adipocyte co-cultures led to elevated secretion of monocyte chemoattractant protein-1 (MCP-1) by primary adipocytes, in part due to TNF-a secretion by activated B cells. Adipocyte-derived MCP-1 resulted in enhanced macrophage migration. Furthermore, the supernatants of the B cell/adipocyte co-culture promoted pro-fibrotic, M2-like macrophage polarization in vitro, correlating with elevated levels of lactate. Single-cell RNA sequencing of human CrF and mouse WAT supported our in vitro findings suggesting that the B cell/adipocyte crosstalk supports a lactate-rich, inflammatory adipose tissue niche. Taken together, our results provide evidence for a crucial role of the B cell/adipocyte crosstalk to CD-associated adipose tissue inflammation. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=184 SRC="FIGDIR/small/664132v1_ufig1.gif" ALT="Figure 1"> View larger version (54K): org.highwire.dtl.DTLVardef@15de8f9org.highwire.dtl.DTLVardef@6a6873org.highwire.dtl.DTLVardef@1ef7a22org.highwire.dtl.DTLVardef@13b89a4_HPS_FORMAT_FIGEXP M_FIG C_FIG One Sentence SummaryO_LIB cells and pro-fibrotic macrophages accumulate in IBD-associated, inflamed adipose tissue C_LIO_LIB cell depletion in a mouse model reduces pro-fibrotic macrophage accumulation in IBD-associated, inflamed adipose tissue C_LIO_LIB cell/adipocyte crosstalk promotes B cell activation and MCP-1 secretion by adipocytes C_LIO_LIAdipocyte-derived MCP-1 promotes migration of macrophages C_LIO_LIB cell/adipocyte crosstalk provides a lactate-rich, inflammatory environment which likely drives pro-fibrotic macrophage polarisation C_LI

immunology↗

Podoplanin-Linked Mesenchymal Shift Synergizes with CCR7 driving Lymphatic Metastasis and Tumor Progression in Breast Cancer

Epithelial-to-mesenchymal-transition (EMT) and upregulation of chemokine receptors are linked to lymphatic metastasis in various types of cancer including breast cancer. However, the underlying molecular mechanisms are not fully understood. Using a triple-negative mammary carcinoma model, conditioned for lymphatic metastasis through expression of the C-C chemokine receptor 7 (CCR7), we identified intrinsic tumor plasticity associated with EMT as a critical determinant for effective metastasis. Specifically, tumor cells upregulate Podoplanin (PDPN) as part of a spontaneous mesenchymal shift that promotes lymphatic dissemination and tumor growth. Intriguingly, the expression of CCR7, or PDPN alone, was not sufficient for these effects. CCR7- and PDPN-positive tumors displayed an immune-cold tumor profile, compared to control, characterized by reduced tumor-infiltrating T-cells. Consistent with this, we found that spontaneous upregulation of PDPN was linked to hypoxia and was associated with the downregulation of homeostatic interferon signaling, and increased expression of collagens. Analysis of single-cell data sets showed that PDPN expression was heterogeneous and correlated significantly with EMT markers, collagen expression, and hypoxia hallmark in human breast cancer cell lines and primary human triple negative (TN) breast cancer, mirroring findings in the mouse model. Further analysis of the human breast cancer METABRIC-microarray datasets supported an association between a high CCR7/PDPN mRNA expression score and aggressive breast cancer subtypes with an independent prognostic value in lymph node-positive tumors. Together, these findings highlight a critical role of tumor microenvironment-driven tumor plasticity and molecular synergy between CCR7 and PDPN-coupled EMT shift in promoting chemokine receptor-mediated tumor dissemination and progression. SummaryCCR7-driven lymphatic metastasis requires a mesenchymal shift with PDPN upregulation. This tumor plasticity, linked to hypoxia and immune evasion, suggests CCR7-PDPN synergy in aggressive breast cancer progression and poor prognosis.

cancer biology↗

Identifying epigenetic biomarkers of established prognostic factors and survival in a clinical cohort of individuals with oropharyngeal cancer

Smoking status, alcohol consumption and HPV infection (acquired through sexual activity) are the predominant risk factors for oropharyngeal cancer and are thought to alter the prognosis of the disease. Here, we conduct epigenome-wide association studies (EWAS) of these factors and [~]3-year survival using Illumina Methylation EPIC blood DNA methylation profiles from 409 individuals in the Head and Neck 5000 (HN5000) study. CpG site associations below our multiple-testing threshold (PBonferroni < 0.05) with both a prognostic factor and with survival were observed in four gene regions: SPEG (smoking), GFI1 (smoking), PPT2 (smoking), and KHD3CL (alcohol consumption). These were further analysed using 2-step Mendelian randomization to assess whether methylation may be a causal mediator of cancer survival. Evidence for mediation was observed only in the SPEG gene region, showing an association with decreased survival (mortality HR: 1.28, 95% CI: 1.14 to 1.43, P: 2.12x10-05). Replication in data from independent datasets, and from HN5000 participants with longer follow-up times is needed to confirm these findings.

epidemiology↗

SNPs associated with HHIP expression have differential effects on lung function in males and females

Adult lung function is highly heritable and 279 genetic loci were recently reported as associated with spirometry-based measures of lung function. Though lung development and function differ between males and females throughout life, there has been no genome-wide study to identify genetic variants with differential effects on lung function in males and females. Here, we present the first genome-wide genotype-by-sex interaction study on four lung function traits in 303,612 participants from the UK Biobank. We detected five SNPs showing genome-wide significant (P<5 x 10-8) interactions with sex on lung function, as well as 21 suggestively significant interactions (P<1 x 10-6). The strongest sex interaction signal came from rs7697189 at 4:145436894 on forced expiratory volume in 1 second (FEV1) (P = 3.15 x 10-15), and was replicated (P = 0.016) in 75,696 individuals in the SpiroMeta consortium. Sex-stratified analyses demonstrated that the minor (C) allele of rs7697189 increased lung function to a greater extent in males than females (untransformed FEV1 {beta} = 0.028 [SE 0.0022] litres in males vs {beta} = 0.009 [SE 0.0014] litres in females), and this effect was not accounted for by differential effects on height, smoking or age at puberty. This SNP resides upstream of the gene encoding hedgehog-interacting protein (HHIP) and has previously been reported for association with lung function and HHIP expression in lung tissue. In our analyses, while HHIP expression in lung tissue was significantly different between the sexes with females having higher expression (most significant probeset P=6.90 x 10-6) after adjusting for age and smoking, rs7697189 did not demonstrate sex differential effects on expression. Establishing the mechanism by which HHIP SNPs have different effects on lung function in males and females will be important for our understanding of lung health and diseases, such as chronic obstructive pulmonary disease (COPD), in both sexes.

genetics↗

The effect of pre-analytical conditions on blood metabolomics in epidemiological studies

BackgroundSerum and plasma are commonly used biofluids for large-scale metabolomic-epidemiology studies. Their metabolomic profile is susceptible to changes due to variability in pre-analytical conditions and the impact of this is unclear.\n\nMethodsParticipant-matched EDTA-plasma and serum samples were collected from 37 non-fasting volunteers and profiled using a targeted nuclear magnetic resonance (NMR) metabolomics platform (N=151 traits). Metabolic concentrations were compared between reference (pre-storage: 4{degrees}C, 1.5h; post-storage: no sample preparation or NMR-analysis delays) and four, pre-storage, blood processing conditions, where samples were incubated at (i) 4{degrees}C, 24h; (ii) 4{degrees}C, 48h; (iii) 21{degrees}C, 24h; (iv) 21{degrees}C, 48h, before centrifugation; and two, post-storage, sample processing conditions in which samples (i) thawed overnight, then left for 24h before addition of sodium buffer followed by immediate NMR analysis; (ii) thawed overnight, addition of sodium buffer, then left for 24h before profiling. Linear regression models with random-intercepts were used to assess the impact of these six pre-analytical conditions on EDTA-plasma/serum metabolome.\n\nResultsFatty acids, beta-hydroxybutyrate, glycoprotein-acetyls and most lipid-related traits, in serum and plasma, were robust to the tested pre and post-storage conditions. Pre-storage conditions impacted concentrations of glycolysis metabolites, acetate, albumin and amino-acids by levels that could potentially bias research results (up to 1.4SD difference compared with reference). Post-storage conditions affected histidine, phenylalanine and LDL-particle-size, with differences up to 1.4SD.\n\nConclusionsMost metabolic traits are robust to the pre- and post-storage conditions tested here and that may commonly occur in large-scale cohorts. However, concentrations of glycolysis metabolites, and amino-acids may be compromised.\n\nKey messagesO_LIIn large scale epidemiological studies, blood processing delays, incubation at high temperature prior to long term storage, and NMR profiling delays after long term storage, may occur.\nC_LIO_LIConcentrations of fatty acids, beta-hydroxybutyrate, glycoprotein acetyls and most lipid-related traits are robust to variations in pre-storage temperature and duration of incubation (4{degrees}C or 21{degrees}C for up to 48h prior to centrifugation) and post-storage sample handling (24h delay in sample preparation or NMR profiling).\nC_LIO_LIGlycolytic metabolite concentrations are altered by pre-storage conditions and amino-acids, particularly histidine and phenylalanine, by both, pre and post-storage conditions.\nC_LI

epidemiology↗

Genomic analysis of diet composition finds novel loci and associations with health and lifestyle

We conducted genome-wide association study (GWAS) meta-analyses of relative caloric intake from fat, protein, carbohydrates and sugar in over 235,000 individuals. We identified 21 approximately independent lead SNPs. Relative protein intake exhibits the strongest relationships with poor health, including positive genetic associations with obesity, type 2 diabetes, and heart disease (rg {approx} 0.15 - 0.5). Relative carbohydrate and sugar intake have negative genetic correlations with waist circumference, waist-hip ratio, and neighborhood poverty (|rg| {approx} 0.1 - 0.3). Overall, our results show that the relative intake of each macronutrient has a distinct genetic architecture and pattern of genetic correlations suggestive of health implications beyond caloric content.

genetics↗

Proof of concept for quantitative urine NMR metabolomics pipeline for large-scale epidemiology and genetics

BackgroundQuantitative molecular data from urine are rare in epidemiology and genetics. NMR spectroscopy could provide these data in high-throughput, and it has already been applied in epidemiological settings to analyse urine samples. However, quantitative protocols for large-scale applications are not available.\n\nMethodsWe describe in detail how to prepare urine samples and perform NMR experiments to obtain quantitative metabolic information. Semi-automated quantitative lineshape fitting analyses were set up for 43 metabolites and applied to data from various analytical test samples and from 1,004 individuals from a population-based epidemiological cohort. Novel analyses on how urine metabolites associate with quantitative serum NMR metabolomics data (61 metabolic measures; n=995) were performed. In addition, confirmatory genome-wide analyses of urine metabolites were conducted (n=578). The fully automated quantitative regression-based spectral analysis is demonstrated for creatinine and glucose (n= 4,548).\n\nResultsIntra-assay metabolite variations were mostly <5% indicating high robustness and accuracy of the urine NMR spectroscopy methodology per se. Intra-individual metabolite variations were large, ranging from 6% to 194%. However, population-based inter-individual metabolite variations were even larger (from 14% to 1655%), providing a sound base for epidemiological applications. Metabolic associations between urine and serum were found clearly weaker than those within serum and within urine, indicating that urinary metabolomics data provide independent metabolic information. Two previous genome-wide hits for formate and 2-hydroxyisobutyrate were replicated at genome-wide significance.\n\nConclusionsQuantitative urine metabolomics data suggest broad novelty for systems epidemiology. A roadmap for an open access methodology is provided.

epidemiology↗

Imprinted loci may be more widespread in humans than previously appreciated and enable limited assignment of parental allelic transmissions in unrelated individuals

Genomic imprinting is an epigenetic mechanism leading to parent-of-origin dependent gene expression. So far, the precise number of imprinted genes in humans is uncertain. In this study, we leveraged genome-wide DNA methylation in whole blood measured longitudinally at 3 time points (birth, childhood and adolescence) and GWAS data in 740 Mother-Child duos from the Avon Longitudinal Study of Parents and Children (ALSPAC) to systematically identify imprinted loci. We reasoned that cis-meQTLs at genomic regions that were imprinted would show strong evidence of parent-of-origin associations with DNA methylation, enabling the detection of imprinted regions. Using this approach, we identified genome-wide significant cis-meQTLs that exhibited parent-of-origin effects (POEs) at 35 novel and 50 known imprinted regions (10-10< P <10-300). Among the novel loci, we observed signals near genes implicated in cardiovascular disease (PCSK9), and Alzheimers disease (CR1), amongst others. Most of the significant regions exhibited imprinting patterns consistent with uniparental expression, with the exception of twelve loci (including the IGF2, IGF1R, and IGF2R genes), where we observed a bipolar-dominance pattern. POEs were remarkably consistent across time points and were so strong at some loci that methylation levels enabled good discrimination of parental transmissions at these and surrounding genomic regions. The implication is that parental allelic transmissions could be modelled at many imprinted (and linked) loci and hence POEs detected in GWAS of unrelated individuals given a combination of genetic and methylation data. Our results indicate that modelling POEs on DNA methylation is effective to identify loci that may be affected by imprinting.

genomics↗

Epigenome-Wide Association Study Of Asthma And Wheeze In Childhood And Adolescence

Asthma heritability has only been partially explained by genetic variants and is known to be sensitive to environmental factors, implicating epigenetic modifications such as DNA methylation in its pathogenesis.\n\nUsing data collected in the Avon Longitudinal Study of Parents and Children (ALSPAC), we assessed associations of asthma and wheeze with DNA methylation at 7.5 years and 16.5 years, at over 450,000 CpG sites in DNA from the peripheral blood of approx. 1000 participants. We used Mendelian randomization (MR), a method of causal inference that uses genetic variants as instrumental variables, to infer the direction of association between DNA methylation and asthma.\n\nWe identified 302 CpGs associated with current asthma status (FDR-adjusted P-value <0.05) and 445 with current wheeze status at 7.5 years, with substantial overlap between the two. Genes annotated to the 302 associated CpGs were enriched for pathways related to movement of cellular/subcellular components, locomotion, interleukin-4 production and eosinophil migration. All associations attenuated when adjusted for eosinophil and neutrophil cell count estimates. At 16.5 years, two sites were associated with current asthma after adjustment for cell counts. The CpGs mapped to the AP2A2 and IL5RA genes, with a -2.32 [95% CI -1.47,-3.18] and -2.49 [95% CI -1.56,-3.43] change in percentage methylation in asthma cases respectively. Two-sample bi-directional MR indicated a causal effect of asthma on DNA methylation at several CpG sites at 7.5 years. However, associations did not persist after adjustment for multiple testing. There was no evidence of a causal effect of asthma on DNA methylation at either of the two CpG sites at 16.5 years.\n\nThe majority of observed associations are driven by higher eosinophil cell counts in asthma cases, acting as an intermediate phenotype, with important implications for future studies of DNA methylation in atopic diseases.

epidemiology↗

Sex-associated autosomal DNA methylation differences are wide-spread and stablethroughout childhood

Almost all species show sexual discordance in many traits and diseases. DNA methylation is known to contribute to these differences through well-established mechanisms including X-inactivation in females, imprinting and parent-of-origin effects. Here we investigate sex discordance in DNA methylation throughout childhood in a sample of 700 individuals from the Avon Longitudinal Study of Parents and Children. We show that autosomal sex-discordant methylation is widespread, affecting approximately 12,000 CpG sites at any given age, and stable; at least 8,500 sites are consistently different across all time points and a large proportion discordant in both the fetal and adult brain cortices. Just over 1,000 methylation differences change from birth to late adolescence, 90% of these between birth and around age seven. Sexually discordant CpG sites are enriched in genomic loci containing androgen but not estrogen targets and in genes involved in tissue development but not housekeeping functions. A methylation-derived sex score capturing the variance was calculated at each time point and found to be highly correlated between time points. This score is nominally associated with sex hormone levels in childhood as well as some phenotypes previously linked to sex hormone levels. These findings suggest that sex-discordant autosomal DNA methylation is widespread throughout the genome, likely due to the first androgen exposures in utero. It is then stably maintained from birth to late adolescence. Methylation variation at sex-discordant sites within the sexes, as summarized by the methylation sex score, likely reflects in utero androgen exposure which is relevant to human health.\n\nSignificance StatementAlthough we know that sex hormones are critical for establishing sexual discordance, less is known about how this discordance is achieved and maintained. Here we present evidence for widespread differences in DNA methylation between male and female children. We show that most of these differences are established prenatally, likely due to the first androgen exposures in utero, and then stably maintained throughout childhood, despite extreme fluctuations in the levels of these very same hormones. Our results support a role for DNA methylation as a means for recording and maintaining the effects of exposure to sex hormones and thus to better understand sexual variation and how it is driven by the prenatal environment.

epidemiology↗

Maternal and fetal genetic contribution to gestational weight gain

BackgroundClinical recommendations to limit gestational weight gain (GWG) imply high GWG is causally related to adverse outcomes in mother or offspring, but GWG is the sum of several inter-related complex phenotypes (maternal fat deposition and vascular expansion, placenta, amniotic fluid and fetal growth). Understanding the genetic contribution to GWG could help clarify the potential effect of its different components on maternal and offspring health. Here we explore the genetic contribution to total, early and late GWG.\n\nParticipants and MethodsA genome-wide association study was used to identify maternal and fetal variants contributing to GWG in up to 10,543 mothers and up to 16,317 offspring of European origin, with replication in 10,660 mothers and 7,561 offspring. Additional analyses determined the proportion of variability in GWG from maternal and fetal common genetic variants and the overlap of established genome-wide significant variants for phenotypes relevant to GWG (e.g. maternal BMI and glucose, birthweight).\n\nResultsWe found that approximately 20% of the variability in GWG was tagged by common maternal genetic variants, and that the fetal genome made a surprisingly minor contribution to explaining variation in GWG. We were unable to identify any genetic variants that reached genome-wide levels of significance (P<5x10-8) and replicated. Some established maternal variants associated with increased BMI, fasting glucose and type 2 diabetes were associated with lower early, and higher later GWG. Maternal variants related to higher systolic blood pressure were related to lower late GWG. Established maternal and fetal birthweight variants were largely unrelated to GWG.\n\nConclusionWe found a modest contribution of maternal common variants to GWG and some overlap of maternal BMI, glucose and type 2 diabetes variants with GWG. These findings suggest that associations between GWG and later offspring/maternal outcomes may be due to the relationship of maternal BMI and diabetes with GWG.

genetics↗