Genetics of interleukin 1 receptor-like 1 in immune and inflammatory diseases

From an understanding of etiopathogenesis to novel therapies-what is new in the treatment of celiac disease?

Celiac disease, a chronic autoimmune disorder caused by genetic factors and exposure to gluten, is increasingly being recognized and diagnosed in both children and adults. Scientists have been searching for a cure for this disease for many years, but despite the impressive development of knowledge in this field, a gluten-free diet remains the only recommended therapy for all patients. At the same time, the increasing diagnosis of celiac disease in adults, which was considered a childhood disease in the 20th century, has opened a discussion on the etiopathology of the disease, which is proven to be very complex and involves genetic, immunological, nutritional, environmental and gut microbiota-related factors. In this review, we extensively discuss these factors and summarize the knowledge of the proposed state-of-the-art treatments for celiac disease to address the question of whether a better understanding of the etiopathogenesis of celiac disease has opened new directions for therapy.

Comprehensive Atlas of Alternative Splicing Reveals NSRP1 Promoting Adipogenesis through CCDC18

Alternative splicing (AS) plays a crucial role in regulating gene expression, function, and diversity. However, limited reports exist on the identification and comparison of AS in Eastern and Western pigs. Here, we analyzed 243 transcriptome data from eight tissues, integrating information on transcription factors (TFs), selection signals, splicing factors (SFs), and quantitative trait loci (QTL) to comprehensively study alternative splicing events (ASEs) in pigs. Five ASE types were identified, with Mutually Exclusive Exon (MXE) and Skipped Exon (SE) ASEs being the most prevalent. A significant portion of genes with ASEs (ASGs) showed conservation across all eight tissues (63.21-76.13% per tissue). Differentially alternative splicing genes (DASGs) and differentially expressed genes (DEGs) exhibited tissue specificity, with blood and adipose tissues having more DASGs. Functional enrichment analysis revealed coDASG_DEGs in adipose were enriched in pathways associated with adipose deposition and immune inflammation, while coDASG_DEGs in blood were enriched in pathways related to immune inflammation and metabolism. Adipose deposition in Eastern pigs might be linked to the down-regulation of immune-inflammation-related pathways and reduced insulin resistance. The TFs, selection signals, and SFs appeared to regulate ASEs. Notably, ARID4A (TF), NSRP1 (SF), ANKRD12, IFT74, KIAA2026, CCDC18, NEXN, PPIG, and ROCK1 genes in adipose tissue showed potential regulatory effects on adipose-deposition traits. NSRP1 could promote adipogenesis by regulating alternative splicing and expression of CCDC18. Conducting an in-depth investigation into AS, this study has successfully identified key marker genes essential for pig genetic breeding and the enhancement of meat quality, which will play important roles in promoting the diversity of pork quality and meeting market demand.

IL18 Gene Polymorphism Is Associated with Total IgE in Adult Subjects with Asthma

The allergic asthma phenotype is characterized by a T helper type 2 (Th2) immune response, based on Immunoglobulin E (IgE)-mediated type 1 hypersensitivity reactions. Total IgE is the sum of all IgE types produced by the human body and is used as a biomarker of inflammation in asthma. We analysed data collected in 143 asthma cases (median age 42.1 years) from the general Italian population (GEIRD survey; 2008-2010) to identify single nucleotide polymorphisms (SNPs) in candidate genes that are associated with total IgE in adult subjects with asthma. These patients reported respiratory symptoms in response to perennial allergens and provided data on 166 SNPs tagging 50 candidate genes or gene regions. Replication of the statistically significant results was performed in 842 asthma cases from other European countries (ECRHS II survey; 1998-2002). SNP rs549908 in interleukin 18 (IL18) gene was significantly associated with total IgE in GEIRD, and this result was replicated in ECRHS II. SNP rs1063320 in the human leukocyte antigen G (HLA-G) gene was identified in GEIRD, but this association was not replicated in ECRHS II. Further investigating IL18 and its biological pathways could be important for developing new therapeutic targets, due to its involvement in inflammatory response processes.

Gene Signatures and Associated Transcription Factors of Allergic Rhinitis: KLF4 Expression Is Associated with Immune Response

This study is aimed at investigating the potential molecular features of allergic rhinitis (AR) and identifying gene signatures and related transcription factors using transcriptome analysis and in silico datasets. Transcriptome profiles were obtained using three independent cohorts (GSE101720, GSE19190, and GSE46171) comprising healthy controls (HC) and patients with AR. The pooled dataset (n = 82) was used to identify the critical signatures of AR compared with HC. Subsequently, key transcription factors were identified by a combined analysis using transcriptome and in silico datasets. Gene ontology: bioprocess (GO: BP) analysis using differentially expressed genes (DEGs) revealed that immune response-related genes were significantly enriched in AR compared with HC. Among them, IL1RL1, CD274, and CD44 were significantly higher in AR patients. We also identified key transcription factors between HC and AR using the in silico dataset and found that AR samples frequently express KLF transcription factor 4 (KLF4), which regulates immune response-related genes including IL1RL1, CD274, and CD44 in human nasal epithelial cells. Our integrative analysis of transcriptomic regulation provides new insights into AR, which may help in developing precision management for patients with AR.

Influence of Genetics on the Response to Omalizumab in Patients with Severe Uncontrolled Asthma with an Allergic Phenotype

Omalizumab is a monoclonal antibody indicated for the treatment of severe uncontrolled asthma with an allergic phenotype. Its effectiveness could be influenced by clinical variables and single nucleotide polymorphisms (SNPs) in one or more of the genes involved in the mechanism of action and process of response to omalizumab, and these could be used as predictive biomarkers of response. We conducted an observational retrospective cohort study that included patients with severe uncontrolled allergic asthma treated with omalizumab in a tertiary hospital. Satisfactory response after 12 months of treatment was defined as (1) Reduction ≥ 50% of exacerbations or no exacerbations, (2) Improvement of lung function ≥ 10% FEV1, and (3) Reduction ≥ 50% of OCS courses or no OCS. Polymorphisms in the FCER1A (rs2251746, rs2427837), FCER1B (rs1441586, rs573790, rs1054485, rs569108), C3 (rs2230199), FCGR2A (rs1801274), FCGR2B (rs3219018, rs1050501), FCGR3A (rs10127939, rs396991), IL1RL1 (rs1420101, rs17026974, rs1921622), and GATA2 (rs4857855) genes were analyzed by real-time polymerase chain reaction (PCR) using TaqMan probes. A total of 110 patients under treatment with omalizumab were recruited. After 12 months of treatment, the variables associated with a reduction in exacerbations were the absence of polyposis (odds ratio [OR] = 4.22; 95% confidence interval [CI] = 0.95-19.63), IL1RL1 rs17026974-AG (OR = 19.07; 95% CI = 1.27-547), and IL1RL1 rs17026974-GG (OR = 16.76; 95% CI = 1.22-438.76). Reduction in oral corticosteroids (OCS) was associated with age of starting omalizumab treatment (OR = 0.95; 95% CI = 0.91-0.99) and blood eosinophil levels > 300 cells/µL (OR = 2.93; 95% CI = 1.01-9.29). Improved lung function showed a relationship to the absence of chronic obstructive pulmonary disease (COPD) (OR = 12.16; 95% CI = 2.45-79.49), FCGR2B rs3219018-C (OR = 8.6; 95% CI = 1.12-117.15), GATA2 rs4857855-T (OR = 15.98; 95% CI = 1.52-519.57) and FCGR2A rs1801274-G (OR = 13.75; 95% CI = 2.14-142.68; AG vs. AA and OR = 7.46; 95% CI = 0.94-89.12; GG vs. AA). Meeting one response criterion was related to FCER1A rs2251746-TT (OR = 24; 95% CI = 0.77-804.57), meeting two to age of asthma diagnosis (OR = 0.93; 95% CI = 0.88-0.99), and meeting all three to body mass index (BMI) < 25 (OR = 14.23; 95% CI = 3.31-100.77) and C3 rs2230199-C (OR = 3; 95% CI = 1.01-9.92). The results of this study show the possible influence of the polymorphisms studied on the response to omalizumab and the clinical benefit that could be obtained by defining predictive biomarkers of treatment response.

Single-cell genomics illustrates heterogeneous phenotypes of myocardial fibroblasts under ischemic insults

Myocardial regenerative strategies are promising where the choice of ideal cell population is crucial for successful translational applications. Herein, we explored the regenerative/repair responses of infarct zone cardiac fibroblast(s) (CF) by unveiling their phenotype heterogeneity at single-cell resolution. CF were isolated from the infarct zone of Yucatan miniswine that suffered myocardial infarction, cultured under simulated ischemic and reperfusion, and grouped into control, ischemia, and ischemia/reperfusion. The single-cell RNA sequencing analysis revealed 19 unique cell clusters suggesting distinct subpopulations. The status of gene expression (log2 fold change (log2 FC) > 2 and log2 FC < -2) was used to define the characteristics of each cluster unveiling with diverse features, including the pro-survival/cardioprotective (Clusters 1, 3, 5, 9, and 18), vasculoprotective (Clusters 2 and 5), anti-inflammatory (Clusters 4 and 17), proliferative (Clusters 4 and 5), nonproliferative (Clusters 6, 8, 11, 16, 17, and 18), proinflammatory (Cluster 6), profibrotic/pathologic (Clusters 8 and 19), antihypertrophic (Clusters 8 and 10), extracellular matrix restorative (Clusters 9 and 12), angiogenic (Cluster 16), and normal (Clusters 7 and 15) phenotypes. Further understanding of these unique phenotypes of CF will provide significant translational opportunities for myocardial regeneration and cardiac management.

DHA Supplementation Attenuates Inflammation-Associated Gene Expression in the Mammary Gland of Lactating Mothers Who Deliver Preterm

BACKGROUND

In a randomized trial of DHA supplementation to lactating mothers who delivered preterm, there were significant increases in DHA status in the mother and her infant.

OBJECTIVES

Our objective here was to characterize the mammary gland transcriptomes from the above study. We hypothesized that proinflammatory gene expression would be attenuated in the increased DHA group compared with the standard DHA group.

METHODS

In the original trial, mothers delivering at <29 wk gestation at the University of Cincinnati Medical Center and intending to express their milk were randomly assigned to supplementation with 200 mg/d DHA (standard group: STD) or 1000 mg/d DHA (experimental group: EXP) within 7 d of delivery. Here, we conducted RNA-seq transcriptome analysis of n = 5 EXP and n = 4 STD extracellular mammary mRNA samples extracted from the fat layer of milk samples obtained 4 wk postenrollment. Transcripts were assessed for differential expression (false discovery rate adjusted P value <0.05) and clustering between EXP compared with STD groups. Ontological analysis of all differentially expressed genes (DEGs) was performed with Toppcluster.

RESULTS

There were 409 DEGs. We observed 5 main groups of biological processes that were upregulated, including those associated with improved immune regulation and management of oxidative stress; and 3 main groups of biological processes that were downregulated, including 1 associated with immune dysregulation. For example, we observed upregulation of inflammation-inhibiting genes including NFKB inhibitor alpha (NFKBIA; fold-change (FC), adjusted P value: FC = 1.70, P = 0.007) and interleukin-18 binding protein (IL18BP: FC = 2.2, adjusted P = 0.02); and downregulation of proinflammatory genes including interleukin 7 receptor (IL7R: FC = -1.9, adjusted P = 0.02) and interleukin 1 receptor like 1 (IL1RL1: FC = -13.0, adjusted P = 0.02).

CONCLUSIONS

Increased DHA supplementation during lactation can modulate the expression of inflammation-related genes within the mammary gland. This might translate to milk composition with a more optimal inflammasome profile. Future research with a larger clinical trial and greater interrogation of clinical outcomes is warranted.

Contribution of the Immune Response in the Ileum to the Development of Diarrhoea caused by Helminth Infection: Studies with the Sheep Model

Gastrointestinal helminths are a global health issue, for humans as well as domestic animals. Most studies focus on the tissues that are infected with the parasite, but here we studied the ileum, a tissue that is rarely infected by helminths. We tested whether inflammation in the ileum contributes to the development and severity of diarrhoea, by comparing sheep that are susceptible (n = 4) or resistant (n = 4) to the disease. We analyzed the ileum transcriptome using RNASeq sequencing approach and various bioinformatics tools including FastQC, STAR, featureCounts, DESeq2, DAVID, clusterProfiler, Cytoscape (ClusterONE) and EnrichR. We identified 243 differentially expressed genes (DEGs), of which 118 were up-regulated and 125 were down-regulated DEGs in the diarrhoea-susceptible animals compared to the diarrhoea-resistant animals. The resulting DEGs were functionally enriched for biological processes, pathways and gene set enrichment analysis. The up-regulated DEGs suggested that an inflammatory immune response was coupled with genes involved in 'Th2 immune response' and 'anti-inflammatory response'. The down-regulated DEGs were related to ion transport, muscle contraction and pathways preventing inflammation. We conclude that i) susceptibility to helminth-induced diarrhoea involves an inflammatory response at a non-infectious site; ii) down-regulation of pathways preventing inflammation can contribute to the severity of diarrhoea; and iii) genes involved in anti-inflammatory responses can reduce the inflammation and diarrhoea.

Synergistic Effects of Weighted Genetic Risk Scores and Resistin and sST2 Levels on the Prognostication of Long-Term Outcomes in Patients with Coronary Artery Disease

Resistin and soluble suppression of tumorigenicity 2 (sST2) are useful predictors in patients with coronary artery disease (CAD). Their serum levels are significantly attributed to variations in RETN and IL1RL1 loci. We investigated candidate variants in the RETN locus for resistin levels and those in the IL1RL1 locus for sST2 levels and evaluated the prognostication of these two biomarkers and the corresponding variants for long-term outcomes in the patients with CAD. We included 4652, 557, and 512 Chinese participants from the Taiwan Biobank (TWB), cardiovascular health examination (CH), and CAD cohorts, respectively. Candidate variants in RETN and IL1RL1 were investigated using whole-genome sequence (WGS) and genome-wide association study (GWAS) data in the TWB cohort. The weighted genetic risk scores (WGRS) of RETN and IL1RL1 with resistin and sST2 levels were calculated. Kaplan–Meier curves were used to analyze the prognostication of resistin and sST2 levels, WGRS of RETN and IL1RL1, and their combinations. Three RETN variants (rs3219175, rs370006313, and rs3745368) and two IL1RL1 variants (rs10183388 and rs4142132) were independently associated with resistin and sST2 levels as per the WGS and GWAS data in the TWB cohort and were further validated in the CH and CAD cohorts. In combination, these variants explained 53.7% and 28.0% of the variation in resistin and sST2 levels, respectively. In the CAD cohort, higher resistin and sST2 levels predicted higher rates of all-cause mortality and major adverse cardiac events (MACEs) during long-term follow-up, but WGRS of RETN and IL1RL1 variants had no impact on these outcomes. A synergistic effect of certain combinations of biomarkers with RETN and IL1RL1 variants was found on the prognostication of long-term outcomes: Patients with high resistin levels/low RETN WGRS and those with high sST2 levels/low IL1RL1 WGRS had significantly higher all-cause mortality and MACEs rates, and those with both these combinations had the poorest outcomes. Both higher resistin and sST2 levels, but not RETN and IL1RL1 variants, predict poor long-term outcomes in patients with CAD. Furthermore, combining resistin and sST2 levels with the WGRS of RETN and IL1RL1 genotyping exerts a synergistic effect on the prognostication of CAD outcomes. Future studies including a large sample size of participants with different ethnic populations are needed to verify this finding.

Association of IL33, IL1RL1, IL1RAP Polymorphisms and Asthma in Chinese Han Children

Background: Genome-wide association studies have identified interleukin 33 (IL33), interleukin 1 receptor-like 1 (IL1RL1), interleukin 1 receptor accessory protein (IL1RAP) as asthma susceptibility loci in Europeans. IL33, IL1RL1, and IL1RAP constitute a ligand-receptor complex.

Objective: We analyzed associations of asthma susceptibility, eosinophilic airway inflammation, and response to inhaled corticosteroid (ICS) with single nucleotide polymorphisms (SNPs) of 3 genes encoding IL33, IL1RL1, and its coreceptor IL1RAP in Chinese Han nationality children.

Methods: A total of 153 non-asthmatic children and 265 asthmatic children who visited the Xiangya Hospital between September 2015 and August 2019 were recruited for this study. Pulmonary function tests, peripheral blood eosinophil counts (PBEC), and fractional exhaled nitric oxide (FeNO) tests were performed before treatment, and 3 months after treatment. Each participant’s DNA was extracted from the peripheral blood, and a Mass ARRAY system was used to genotype the SNPs.

Results: The T allele of rs4742170 in IL33 was associated with a risk of higher FeNO at baseline, and no improvement in FeNO and airway hyperresponsiveness was found after ICS treatment. The A allele of rs10208293 and C allele of rs13424006 in IL1RL1 both were associated with lower susceptibility to asthma and lower FeNO. The TT genotype of rs1420101 and AA genotype of rs4142132 in IL1RL1 were associated with a greater probability of improvement in PBEC after ICS treatment.

Conclusion: IL33-IL1RL1-IL1RAP complex polymorphisms are associated with childhood asthma susceptibility, eosinophilic airway inflammation, and ICS response in Chinese Han children in Hunan. We speculate that IL33-IL1RL1-IL1RAP complex polymorphisms affect the development of asthma, airway inflammation, and subsequent ICS response in childhood.

IL1RL1 single nucleotide polymorphisms are associated with asthma in the Iranian population

Asthma is a chronic and multifactorial disease which is known to result from environmental and genetic factors. Interleukin 1 receptor-like 1 (IL1RL1) is a receptor, which promotes inflammatory responses after binding to its ligand IL-33. Several studies have shown that IL1RL1 gene polymorphisms are related to susceptibility or protection to asthma. The objective of this study was to evaluate the association between two IL1RL1 single nucleotide polymorphisms (rs10208293 and rs1041973) and the risk of asthma in the Iranian population. We performed genotyping of the IL1RL1 SNPs in 126 adult asthmatics and 300 healthy controls using TaqMan genotyping assay. Moreover, total serum IgE level, eosinophil count, and skin prick test were accomplished. The results indicated that the AA genotype of rs10208293 was positively associated with asthma susceptibility (p=0.028). We did not find any association between rs1041973 and asthma. Overall, our findings indicate that rs10208293 has a positive association with asthma in the Iranian population.

Familial Mediterranean fever-related miR-197-3p targets IL1R1 gene and modulates inflammation in monocytes and synovial fibroblasts

Familial Mediterranean fever (FMF); is an autosomal recessively inherited autoinflammatory disease caused by the mutations in the Mediterranean Fever (MEFV) gene. Recent studies have shown that epigenetic control mechanisms, particularly non-coding RNAs, may play a role in the pathogenesis of autoinflammation. microRNAs (miRNAs) are small non-coding RNAs that play critical roles in regulating host gene expression at the post-transcriptional level. The phenotypic heterogeneity of FMF disease suggests that FMF may not be a monogenic disease, suggesting that epigenetic factors may affect phenotypic presentation. Here we examined the potential anti-inflammatory effect of miR-197-3p, which is a differentially expressed miRNA in FMF patients, by using inflammation related functional assays. We monitored gene expression levels of important cytokines, as well as performed functional studies on IL-1β secretion, caspase-1 activation, apoptosis assay, and cell migration assay. These experiments were used to evaluate the different stages of inflammation following pre-miR-197 transfection. Anti-miR-197 transfections were performed to test the opposite effect. 3′UTR luciferase activity assay was used for target gene studies. Our results obtained by inflammation-related functional assays demonstrated an anti-inflammatory effect of miR-197-3p in different cell types (synovial fibroblasts, monocytes, macrophages). 3′UTR luciferase activity assay showed that miR-197-3p directly binds to the interleukin-1beta (IL-1β) receptor, type I (IL1R1) gene, which is one of the key molecules of the inflammatory pathways. This study may contribute to understand the role of miR-197-3p in autoinflammation process. Defining the critical miRNAs may guide the medical community in a more personalized medicine in autoinflammatory diseases.

Soluble ST2: A complex and diverse role in several diseases

The Suppression of Tumorigenicity 2 protein (ST2) is a member of the interleukin (IL) 1 receptor family with transmembrane (ST2L) and soluble (sST2) isoforms that are (over)expressed in several cells in different conditions and following various triggers (e.g. inflammation, stress). The ligand of ST2 is IL-33, which on binding to ST2L results in nuclear signalling and immunomodulatory action in various cells (tumour, immune, heart). sST2, that is released in the circulation, functions as a »decoy« receptor of IL-33 and inhibits IL-33/ST2L signalling and beneficial effects. The importance and role of the ST2/IL-33 axis and sST2 have been evaluated and confirmed in several inflammatory, cancer and cardiac diseases. sST2 is involved in homeostasis/pathogenesis of these diseases, as the counterbalance/response on IL-33/ST2L axis activation, which is triggered and expressed during developing fibrosis, tissue damage/inflammation and remodelling. In clinical studies, sST2 has been recognised as an important prognostic marker in patients with cardiac disease, including patients with chronic kidney disease where specific characteristics of sST2 enable better assessment of the risk of End-Stage Renal Disease patients on dialysis. sST2 is also recognised as an important marker for monitoring treatment in heart failure patients. However, accurate measurement and interpretation of ST2 concentration in serum/plasma samples for routine and research applications require the use of appropriate methods and recognition of essential characteristics of both the methods and the analyte that may influence the result. sST2, as one of the most promising disease biomarkers, is deserving of further study and wider application in clinical practice.

Extensive Changes in Transcriptomic "Fingerprints" and Immunological Cells in the Large Organs of Patients Dying of Acute Septic Shock and Multiple Organ Failure Caused by Neisseria meningitidis

Background: Patients developing meningococcal septic shock reveal levels of Neisseria meningitidis (10⁶-10⁸/mL) and endotoxin (10¹-10³ EU/mL) in the circulation and organs, leading to acute cardiovascular, pulmonary and renal failure, coagulopathy and a high case fatality rate within 24 h. Objective: To investigate transcriptional profiles in heart, lungs, kidneys, liver, and spleen and immunostain key inflammatory cells and proteins in post mortem formalin-fixed, paraffin-embedded (FFPE) tissue samples from meningococcal septic shock patients. Patients and Methods: Total RNA was isolated from FFPE and fresh frozen (FF) tissue samples from five patients and two controls (acute non-infectious death). Differential expression of genes was detected using Affymetrix microarray analysis. Lung and heart tissue samples were immunostained for T-and B cells, macrophages, neutrophils and the inflammatory markers PAI-1 and MCP-1. Inflammatory mediators were quantified in lysates from FF tissues. Results: The transcriptional profiles showed a complex pattern of protein-coding and non-coding RNAs with significant regulation of pathways associated with organismal death, cell death and survival, leukocyte migration, cellular movement, proliferation of cells, cell-to-cell signaling, immune cell trafficking, and inflammatory responses in an organ-specific clustering manner. The canonical pathways including acute phase response-, EIF2-, TREM1-, IL-6-, HMBG1-, PPAR signaling, and LXR/RXR activation were associated with acute heart, pulmonary, and renal failure. Fewer genes were regulated in the liver and particularly in the spleen. The main upstream regulators were TNF, IL-1β, IL-6, RICTOR, miR-6739-3p, and CD3. Increased numbers of inflammatory cells (CD68+, MPO+, CD3+, and CD20+) were found in lungs and heart. PAI-1 inhibiting fibrinolysis and MCP-1 attracting leukocyte were found significantly present in the septic tissue samples compared to the controls. Conclusions: FFPE tissue samples can be suitable for gene expression studies as well as immunostaining of specific cells or molecules. The most pronounced gene expression patterns were found in the organs with highest levels of Neisseria meningitidis DNA. Thousands of protein-coding and non-coding RNA transcripts were altered in lungs, heart and kidneys. We identified specific biomarker panels both protein-coding and non-coding RNA transcripts, which differed from organ to organ. Involvement of many genes and pathways add up and the combined effect induce organ failure.

Construction of miRNA-target networks using microRNA profiles of CVB3-infected HeLa cells

MicroRNAs (miRNAs) play an important role in regulating gene expression in multiple biological processes and diseases. Thus, to understand changes in miRNA during CVB3 infection, specific miRNA expression profiles were investigated at 3 h, 6 h, and 9 h postinfection in HeLa cells by small-RNA high-throughput sequencing. Biological implications of 68 differentially expressed miRNAs were analyzed through GO and KEGG pathways. Interaction networks between 34 known highly differentially expressed miRNAs and targets were constructed by mirDIP and Navigator. The predicted targets showed that FAM135A, IKZF2, PLAG1, ZNF148, PHC3, LCOR and DYRK1A, which are associated with cellular differentiation and transcriptional regulation, were recognized by 8 miRNAs or 9 miRNAs through interactional regulatory networks. Seven target genes were confirmed by RT-qPCR. The results showed that the expression of DYRK1A, FAM135A, PLAG1, ZNF148, and PHC3 were obviously inhibited at 3 h, 6 h, and 9 h postinfection. The expression of LCOR did not show a significant change, and the expression of IKZF2 increased gradually with prolonged infection time. Our findings improve the understanding of the pathogenic mechanism of CVB3 infection on cellular differentiation and development through miRNA regulation, which has implications for interventional approaches to CVB3-infection therapy. Our results also provide a new method for screening target genes of microRNA regulation in virus-infected cells.

Using Transcriptomic Hidden Variables to Infer Context-Specific Genotype Effects in the Brain

Deciphering the environmental contexts at which genetic effects are most prominent is central for making full use of GWAS results in follow-up experiment design and treatment development. However, measuring a large number of environmental factors at high granularity might not always be feasible. Instead, here we propose extracting cellular embedding of environmental factors from gene expression data by using latent variable (LV) analysis and taking these LVs as environmental proxies in detecting gene-by-environment (GxE) interaction effects on gene expression, i.e., GxE expression quantitative trait loci (eQTLs). Applying this approach to two largest brain eQTL datasets (n = 1,100), we show that LVs and GxE eQTLs in one dataset replicate well in the other dataset. Combining the two samples via meta-analysis, 895 GxE eQTLs are identified. On average, GxE effect explains an additional ∼4% variation in expression of each gene that displays a GxE effect. Ten of these 52 genes are associated with cell-type-specific eQTLs, and the remaining genes are multi-functional. Furthermore, after substituting LVs with expression of transcription factors (TF), we found 91 TF-specific eQTLs, which demonstrates an important use of our brain GxE eQTLs.

Genomic analysis reveals genes affecting distinct phenotypes among different Chinese and western pig breeds

The differences in artificial and natural selection have been some of the factors contributing to phenotypic diversity between Chinese and western pigs. Here, 830 individuals from western and Chinese pig breeds were genotyped using the reduced-representation genotyping method. First, we identified the selection signatures for different pig breeds. By comparing Chinese pigs and western pigs along the first principal component, the growth gene IGF1R; the immune genes IL1R1, IL1RL1, DUSP10, RAC3 and SWAP70; the meat quality-related gene SNORA50 and the olfactory gene OR1F1 were identified as candidate differentiated targets. Further, along a principal component separating Pudong White pigs from others, a potential causal gene for coat colour (EDNRB) was discovered. In addition, the divergent signatures evaluated by F_st within Chinese pig breeds found genes associated with the phenotypic features of coat colour, meat quality and feed efficiency among these indigenous pigs. Second, admixture and genomic introgression analysis were performed. Shan pigs have introgressed genes from Berkshire, Yorkshire and Hongdenglong pigs. The results of introgression mapping showed that this introgression conferred adaption to the local environment and coat colour of Chinese pigs and the superior productivity of western pigs.

Reproductive, Physiological, and Molecular Outcomes in Female Mice Deficient in Dhh and Ihh

Ovarian development requires coordinate communications among oocytes, granulosa cells, and theca cells. Two Hedgehog (Hh) pathway ligands, Desert hedgehog (Dhh) and Indian hedgehog (Ihh), are produced by the granulosa cells and work together to regulate theca cell specification and development. Mice lacking both Dhh and Ihh had loss of normal ovarian function, which raised the question of which biological actions are specifically controlled by each ligand during folliculogenesis. By comparing the reproductive fitness, hormonal profiles, and ovarian transcriptomes among control, Dhh single-knockout (KO), Ihh KO, and Dhh/Ihh double-knockout (DKO) mice, we examined the specific roles of Dhh and Ihh in these processes. Dhh/Ihh DKO female mice were infertile because of a lack of theca cells and their steroid product androgen. Although Dhh and Ihh KO mice were fertile with normal folliculogenesis, they had decreased androgen production and alterations in their ovarian transcriptomes. Absence of Ihh led to aberrant steroidogenesis and elevated inflammation responses, which were not found in Dhh KO mouse ovaries, implicating that IHH has a greater impact than DHH on the activation of the Hh signaling pathway in the ovary. Our findings provide insight into not only how the Hh pathway influences folliculogenesis but also the distinct and overlapping roles of Dhh and Ihh in supporting ovarian development.

Genetic regulation of IL1RL1 methylation and IL1RL1-a protein levels in asthma

Interleukin-1 receptor-like 1 (IL1RL1) is an important asthma gene. (Epi)genetic regulation of IL1RL1 protein expression has not been established. We assessed the association between IL1RL1 single nucleotide polymorphisms (SNPs), IL1RL1 methylation and serum IL1RL1-a protein levels, and aimed to identify causal pathways in asthma.Associations of IL1RL1 SNPs with asthma were determined in the Dutch Asthma Genome-wide Association Study cohort and three European birth cohorts, BAMSE (Children/Barn, Allergy, Milieu, Stockholm, an Epidemiological survey), INMA (Infancia y Medio Ambiente) and PIAMA (Prevention and Incidence of Asthma and Mite Allergy), participating in the Mechanisms of the Development of Allergy study. We performed blood DNA IL1RL1 methylation quantitative trait locus (QTL) analysis (n=496) and (epi)genome-wide protein QTL analysis on serum IL1RL1-a levels (n=1462). We investigated the association of IL1RL1 CpG methylation with asthma (n=632) and IL1RL1-a levels (n=548), with subsequent causal inference testing. Finally, we determined the association of IL1RL1-a levels with asthma and its clinical characteristics (n=1101).IL1RL1 asthma-risk SNPs strongly associated with IL1RL1 methylation (rs1420101; p=3.7×10^-16) and serum IL1RL1-a levels (p=2.8×10^-56). IL1RL1 methylation was not associated with asthma or IL1RL1-a levels. IL1RL1-a levels negatively correlated with blood eosinophil counts, whereas there was no association between IL1RL1-a levels and asthma.In conclusion, asthma-associated IL1RL1 SNPs strongly regulate IL1RL1 methylation and serum IL1RL1-a levels, yet neither these IL1RL1-methylation CpG sites nor IL1RL1-a levels are associated with asthma.

IL-1 receptor like 1 protects against alcoholic liver injury by limiting NF-κB activation in hepatic macrophages

BACKGROUND & AIM

Alcohol consumption increases intestinal permeability and causes damage to hepatocytes, leading to the release of pathogen- and damage-associated molecular pattern molecules (PAMPs and DAMPs), stimulating hepatic macrophages and activating NF-κB. The resultant inflammation exacerbates alcoholic liver disease (ALD). However, much less is known about the mechanisms attenuating inflammation and preventing disease progression in most heavy drinkers. Interleukin (IL)-33 is a DAMP (alarmin) released from dead cells that acts through its receptor, IL-1 receptor like 1 (ST2). ST2 signaling has been reported to either stimulate or inhibit NF-κB activation. The role of IL-33/ST2 in ALD has not been studied.

METHODS

Serum levels of IL-33 and its decoy receptor, soluble ST2 (sST2) were measured in ALD patients. Alcohol-induced liver injury, inflammation and hepatic macrophage activation were compared between wild-type, IL-33-/- and ST2-/- mice in several models.

RESULTS

Elevation of serum IL-33 and sST2 were only observed in patients with severe decompensated ALD. Consistently, in mice with mild ALD without significant cell death and IL-33 release, IL-33 deletion did not affect alcohol-induced liver damage. However, ST2-deletion exacerbated ALD, through enhancing NF-κB activation in liver macrophages. In contrast, when extracellular IL-33 was markedly elevated, liver injury and inflammation were attenuated in both IL-33-/- and ST2-/- mice compared to wild-type mice.

CONCLUSION

Our data revealed a dichotomous role of IL-33/ST2 signaling during ALD development. At early and mild stages, ST2 restrains the inflammatory activation of hepatic macrophages, through inhibiting NF-κB, and plays a protective function in an IL-33-independent fashion. During severe liver injury, significant cell death and marked IL-33 release occur, which triggers IL-33/ST2 signaling and exacerbates tissue damage.

LAY SUMMARY

In mild ALD, ST2 negatively regulates the inflammatory activation of hepatic macrophages, thereby protecting against alcohol-induced liver damage, whereas in the case of severe liver injury, the release of extracellular IL-33 may exacerbate tissue inflammation by triggering the canonical IL-33/ST2L signaling in hepatic macrophages.

A functional variant in ST2 gene is associated with risk of hypertension via interfering MiR-202-3p

Recent studies have suggested that interleukin 1 receptor-like 1 (ST2) plays a critical role in pathogenesis of several cardiovascular disease conditions. In this study, we examined association of 13 single nucleotide polymorphisms (SNPs) of ST2 gene with essential hypertension (EH) risk in 1151 patients with EH and 1135 controls. Our study showed that variants rs11685424, rs12999364 and rs3821204 are highly associated with an increase in risk of EH, while rs6543116 is associated with a decrease risk of EH. Notably, in silico analyses suggested the G>C change of rs3821204, which located within the 3'UTR of soluble ST2 mRNA, disrupted a putative binding site for miR202-3p. Functional analyses suggested that miR-202-3p significantly decreased soluble ST2-G mRNA stability and inhibited its endogenous expression. Furthermore, we found increased plasma-soluble ST2 (sST2) level was highly associated with CC genotype of rs3821204 in vivo. Taken together, our findings provide the first evidence that genetic variants in ST2 gene are associated with EH risk and variant rs3821204 may influence the development of EH by controlling sST2 expression.

Antiinflammatory Effects of Budesonide in Human Fetal Lung

Lung inflammation in premature infants contributes to the development of bronchopulmonary dysplasia (BPD), a chronic lung disease with long-term sequelae. Pilot studies administering budesonide suspended in surfactant have found reduced BPD without the apparent adverse effects that occur with systemic dexamethasone therapy. Our objective was to determine budesonide potency, stability, and antiinflammatory effects in human fetal lung. We cultured explants of second-trimester fetal lung with budesonide or dexamethasone and used microscopy, immunoassays, RNA sequencing, liquid chromatography/tandem mass spectrometry, and pulsating bubble surfactometry. Budesonide suppressed secreted chemokines IL-8 and CCL2 (MCP-1) within 4 hours, reaching a 90% decrease at 12 hours, which was fully reversed 72 hours after removal of the steroid. Half-maximal effects occurred at 0.04-0.05 nM, representing a fivefold greater potency than for dexamethasone. Budesonide significantly induced 3.6% and repressed 2.8% of 14,500 sequenced mRNAs by 1.6- to 95-fold, including 119 genes that contribute to the glucocorticoid inflammatory transcriptome; some are known targets of nuclear factor-κB. By global proteomics, 22 secreted inflammatory proteins were hormonally regulated. Two glucocorticoid-regulated genes of interest because of their association with lung disease are CHI3L1 and IL1RL1. Budesonide retained activity in the presence of surfactant and did not alter its surface properties. There was some formation of palmitate-budesonide in lung tissue but no detectable metabolism to inactive 16α-hydroxy prednisolone. We concluded that budesonide is a potent and stable antiinflammatory glucocorticoid in human fetal lung in vitro, supporting a beneficial antiinflammatory response to lung-targeted budesonide:surfactant treatment of infants for the prevention of BPD.

The role of ST2 and ST2 genetic variants in schistosomiasis

BACKGROUND

Chronic schistosomiasis and its severe complication, periportal fibrosis, are characterized by a predominant T_h2 response. To date, specific single nucleotide polymorphisms in ST2 have been some of the most consistently associated genetic variants for asthma.

OBJECTIVE

We investigated the role of ST2 (a receptor for the T_h2 cytokine IL-33) in chronic and late-stage schistosomiasis caused by Schistosoma japonicum and the potential effect of ST2 genetic variants on stage of disease and ST2 expression.

METHODS

We recruited 947 adult participants (339 with end-stage schistosomiasis and liver cirrhosis, 307 with chronic infections without liver fibrosis, and 301 health controls) from a S japonicum-endemic area (Hubei, China). Six ST2 single nucleotide polymorphisms were genotyped. Serum soluble ST2 (sST2) was measured by ELISA, and ST2 expression in normal liver tissues, Hepatitis B virus-induced fibrotic liver tissues, and S japonicum-induced fibrotic liver tissues was measured by immunohistochemistry.

RESULTS

We found sST2 levels were significantly higher in the end-stage group (36.04 [95% CI, 33.85-38.37]) compared with chronic cases and controls (22.7 [95% CI, 22.0-23.4], P < 1E-10). In addition, S japonicum-induced fibrotic liver tissues showed increased ST2 staining compared with normal liver tissues (P = .0001). Markers rs12712135, rs1420101, and rs6543119 were strongly associated with sST2 levels (P = 2E-10, 5E-05, and 6E-05, respectively), and these results were replicated in an independent cohort from Brazil living in a S mansoni endemic region.

CONCLUSIONS

We demonstrate for the first time that end-stage schistosomiasis is associated with elevated sST2 levels and show that ST2 genetic variants are associated with sST2 levels in patients with schistosomiasis.

The genetic and epigenetic landscapes of the epithelium in asthma

Asthma is a global health problem with increasing prevalence. The airway epithelium is the initial barrier against inhaled noxious agents or aeroallergens. In asthma, the airway epithelium suffers from structural and functional abnormalities and as such, is more susceptible to normally innocuous environmental stimuli. The epithelial structural and functional impairments are now recognised as a significant contributing factor to asthma pathogenesis. Both genetic and environmental risk factors play important roles in the development of asthma with an increasing number of genes associated with asthma susceptibility being expressed in airway epithelium. Epigenetic factors that regulate airway epithelial structure and function are also an attractive area for assessment of susceptibility to asthma. In this review we provide a comprehensive discussion on genetic factors; from using linkage designs and candidate gene association studies to genome-wide association studies and whole genome sequencing, and epigenetic factors; DNA methylation, histone modifications, and non-coding RNAs (especially microRNAs), in airway epithelial cells that are functionally associated with asthma pathogenesis. Our aims were to introduce potential predictors or therapeutic targets for asthma in airway epithelium. Overall, we found very small overlap in asthma susceptibility genes identified with different technologies. Some potential biomarkers are IRAKM, PCDH1, ORMDL3/GSDMB, IL-33, CDHR3 and CST1 in airway epithelial cells. Recent studies on epigenetic regulatory factors have further provided novel insights to the field, particularly their effect on regulation of some of the asthma susceptibility genes (e.g. methylation of ADAM33). Among the epigenetic regulatory mechanisms, microRNA networks have been shown to regulate a major portion of post-transcriptional gene regulation. Particularly, miR-19a may have some therapeutic potential.

Characterising the immune profile of the kidney biopsy at lupus nephritis flare differentiates early treatment responders from non-responders

Introduction

The kidney biopsy is used to diagnose and guide initial therapy in patients with lupus nephritis (LN). Kidney histology does not correlate well with clinical measurements of kidney injury or predict how patients will respond to standard-of-care immunosuppression. We postulated that the gene expression profile of kidney tissue at the time of biopsy may differentiate patients who will from those who will not respond to treatment.

Methods

The expression of 511 immune-response genes was measured in kidney biopsies from 19 patients with proliferative LN and 4 normal controls. RNA was extracted from formalin-fixed, paraffin-embedded kidney biopsies done at flare. After induction therapy, 5 patients achieved a complete clinical response (CR), 10 had a partial response (PR) and 4 patients were non-responders (NRs). Transcript expression was compared with normal controls and between renal response groups.

Results

A principal component analysis showed that intrarenal transcript expression from normal kidney, CR biopsies and NR biopsies segregated from each other. The top genes responsible for CR clustering included several interferon pathway genes (STAT1, IRF1, IRF7, MX1, STAT2, JAK2), while complement genes (C1R, C1QB, C6, C9, C5, MASP2) were mainly responsible for NR clustering. Overall, 35 genes were uniquely expressed in NR compared with CR. Pathway analysis revealed that interferon signalling and complement activation pathways were upregulated in both groups, while BAFF, APRIL, nuclear factor-κB and interleukin-6 signalling were increased in CR but suppressed in NR.

Conclusions

These data suggest that molecular profiling of the kidney biopsy at LN flare may be useful in predicting treatment response to induction therapy.

Can Serum ST2 Levels Be Used as a Marker of Fibrosis in Chronic Hepatitis B Infection?

Interleukin 33 (IL-33) is a cytokine belonging to the IL-1 superfamily. Soluble ST2 (sST2) binds to IL-33 and by functioning as trap receptor inhibits signal sending to Th2 via transmembrane ST2. Because Th2-type cytokines play an important role in fibrosis, the aim of this study is to determine whether sST2 can be used as a marker of fibrosis in chronic hepatitis B (CHB) patients or not.The study included 19 healthy controls, 54 patients with CHB, and 14 patients with cirrhosis because of CHB. The aspartate aminotransferase-to-platelet ratio index (APRI) and fibrosis index based on the 4 factors (FIB-4) scores also calculated, and correlations between liver biopsies, sST2 levels, and these scores were analyzed in CHB and cirrhosis patients.The sST2 levels in patients with CHB were significantly higher than those in the control group subjects (median: 1133 pg/mL vs 762.5 pg/mL, respectively [P = 0.035]). In CHB patients, the METAVIR fibrosis score (stages from 0 to 4) showed a moderate correlation with serum sST2 level (r = 0.396, P = 0.004) and a weak correlation with FIB-4 score (r = 0.359, P = 0.008), but no correlation with APRI score (r = 0.253, P = 0.06). The under the curve value of serum sST2 was 0.68, and its prediction of significant fibrosis (METAVIR score ≥2) in values >674 pg/mL had a sensitivity of 91.7% and specificity of 40% (P = 0.009). According to multiple logistic regression analysis, only METAVIR fibrosis stage was found to be an independent predictor of serum sST2 elevation in CHB patients (P = 0.04).The sST2 level can be used for differentiating significant fibrosis from mild fibrosis in CHB patients. However, the efficacy of this marker should be verified by larger studies in the future.

Respiratory Syncytial Virus Disease Is Mediated by Age-Variable IL-33

Respiratory syncytial virus (RSV) is the most common cause of infant hospitalizations and severe RSV infections are a significant risk factor for childhood asthma. The pathogenic mechanisms responsible for RSV induced immunopathophysiology remain elusive. Using an age-appropriate mouse model of RSV, we show that IL-33 plays a critical role in the immunopathogenesis of severe RSV, which is associated with higher group 2 innate lymphoid cells (ILC2s) specifically in neonates. Infection with RSV induced rapid IL-33 expression and an increase in ILC2 numbers in the lungs of neonatal mice; this was not observed in adult mice. Blocking IL-33 with antibodies or using an IL-33 receptor knockout mouse during infection was sufficient to inhibit RSV immunopathogenesis (i.e., airway hyperresponsiveness, Th2 inflammation, eosinophilia, and mucus hyperproduction); whereas administration of IL-33 to adult mice during RSV infection was sufficient to induce RSV disease. Additionally, elevated IL-33 and IL-13 were observed in nasal aspirates from infants hospitalized with RSV; these cytokines declined during convalescence. In summary, IL-33 is necessary, either directly or indirectly, to induce ILC2s and the Th2 biased immunopathophysiology observed following neonatal RSV infection. This study provides a mechanism involving IL-33 and ILC2s in RSV mediated human asthma.

Pathogenesis of Myeloproliferative Neoplasms: Role and Mechanisms of Chronic Inflammation

Myeloproliferative neoplasms (MPNs) are a heterogeneous group of clonal diseases characterized by the excessive and chronic production of mature cells from one or several of the myeloid lineages. Recent advances in the biology of MPNs have greatly facilitated their molecular diagnosis since most patients present with mutation(s) in the JAK2, MPL, or CALR genes. Yet the roles played by these mutations in the pathogenesis and main complications of the different subtypes of MPNs are not fully elucidated. Importantly, chronic inflammation has long been associated with MPN disease and some of the symptoms and complications can be linked to inflammation. Moreover, the JAK inhibitor clinical trials showed that the reduction of symptoms linked to inflammation was beneficial to patients even in the absence of significant decrease in the JAK2-V617F mutant load. These observations suggested that part of the inflammation observed in patients with JAK2-mutated MPNs may not be the consequence of JAK2 mutation. The aim of this paper is to review the different aspects of inflammation in MPNs, the molecular mechanisms involved, the role of specific genetic defects, and the evidence that increased production of certain cytokines depends or not on MPN-associated mutations, and to discuss possible nongenetic causes of inflammation.

Association analysis between genetic variants in interleukin genes among different populations with hyperuricemia in Xinjiang Autonomous Region

To investigate whether functional variants of five interleukin genes (IL-1β, IL-10, IL-8, IL-18 and IL-18RAP) are associated with susceptibility to hyperuricemia among different nationalities (including Uygur, Kazak and Han populations) in the Xinjiang Autonomous Region of China. A total of 884 hyperuricemia patients and 1316 matched controls were recruited from the First Affiliated Hospital of Xinjiang Medical University in Urumqi. After genotyping of rs4073 in IL-8, rs16944 in IL-1, rs187238 in IL-18, rs1800871 in IL-10 and rs13015714 in IL-18RAP by TaqMan allele discrimination assays, an association analysis was performed using the χ(2) test as well as a genotype-phenotype analysis. For the Uygur population, IL-8 rs4073, IL-18 rs187238 and IL-18RAP rs130154 polymorphisms were all associated with hyperuricemia (P<0.001 by genotype and P=0.008, OR 0.802 by allele for IL-8; P=0.01 by genotype and P=0.006, OR 1.332 by allele for IL-18 rs187238; P=0.007 by genotype and P=0.005, OR 1.27 by allele for IL-18RAP rs130154). For the Kazak population, only IL-18 rs187238 showed statistical significance with hyperuricemia (P=0.002 by genotype and P=0.007, OR 1.823 by allele). However, no differences were found between the five SNPs and hyperuricemia among the Han population. This study demonstrated genetic polymorphisms of different interleukin genes related to hyperuricemia vary in different nationalities in the Xinjiang Autonomous Region because of different geographical environments. IL-8, IL-1RL1 and IL-18 might be involved in the development of hyperuricemia in the Uygur population, whereas only IL-18 might be involved in the Kazak population.

Activated mast cells synthesize and release soluble ST2-a decoy receptor for IL-33

IL-33 released from damaged cells plays a central role in allergic inflammation by acting through its membrane-bound receptor, ST2 receptor (ST2L). IL-33 activity can be neutralized by the soluble spliced variant of ST2 (sST2) that has been associated with allergic inflammation but its source is not well defined. We investigated whether mast cells (MCs) are a significant source of sST2 following activation through FcεRI or ST2. We find that antigen and IL-33 induce substantial production and release of sST2 from human and mouse MCs in culture and do so synergistically when added together or in combination with stem cell factor. Moreover, increases in circulating sST2 during anaphylaxis in mice were dependent on the presence of MCs. Human MCs activated via FcεRI failed to generate IL-33 and IL-33 produced by mouse bone marrow-derived MCs was retained within the cells. Therefore, FcεRI-mediated sST2 production is independent of MC-derived IL-33 acting in an autocrine manner. These results are consistent with the conclusion that both mouse and human MCs when activated are a significant inducible source of sST2 but not IL-33 and thus have the ability to modulate the biologic impact of IL-33 produced locally by other cell types during allergic inflammation.

DNA methylation and childhood asthma in the inner city

BACKGROUND

Epigenetic marks are heritable, influenced by the environment, direct the maturation of T lymphocytes, and in mice enhance the development of allergic airway disease. Thus it is important to define epigenetic alterations in asthmatic populations.

OBJECTIVE

We hypothesize that epigenetic alterations in circulating PBMCs are associated with allergic asthma.

METHODS

We compared DNA methylation patterns and gene expression in inner-city children with persistent atopic asthma versus healthy control subjects by using DNA and RNA from PBMCs. Results were validated in an independent population of asthmatic patients.

RESULTS

Comparing asthmatic patients (n = 97) with control subjects (n = 97), we identified 81 regions that were differentially methylated. Several immune genes were hypomethylated in asthma, including IL13, RUNX3, and specific genes relevant to T lymphocytes (TIGIT). Among asthmatic patients, 11 differentially methylated regions were associated with higher serum IgE concentrations, and 16 were associated with percent predicted FEV1. Hypomethylated and hypermethylated regions were associated with increased and decreased gene expression, respectively (P < 6 × 10(-12) for asthma and P < .01 for IgE). We further explored the relationship between DNA methylation and gene expression using an integrative analysis and identified additional candidates relevant to asthma (IL4 and ST2). Methylation marks involved in T-cell maturation (RUNX3), TH2 immunity (IL4), and oxidative stress (catalase) were validated in an independent asthmatic cohort of children living in the inner city.

CONCLUSIONS

Our results demonstrate that DNA methylation marks in specific gene loci are associated with asthma and suggest that epigenetic changes might play a role in establishing the immune phenotype associated with asthma.

A lack of association between the IKZF2 rs12619285 polymorphism and coronary heart disease

The IKZF2 rs12619285 polymorphism is associated with the eosinophil count, which has multidimensional functions in the pathogenesis of coronary heart disease (CHD). The aim of the present study was to investigate the contribution of the IKZF2 rs12619285 polymorphism to the risk of CHD in a Han Chinese population. In total, 721 CHD cases and 631 non-CHD controls were recruited for an association study of the IKZF2 rs12619285 polymorphism. Genotyping was performed using the melting temperature-shift polymerase chain reaction method. No statistically significant association was observed between the IKZF2 rs12619285 polymorphism and CHD (odds ratio, 1.139, 95% confidence interval, 0.927-1.334; P=0.17). In addition, subgroup analyses by gender or age were unable to identify any association between IKZF2 rs12619285 and CHD (P>0.05), and there was no significant correlation between IKZF2 rs12619285 and the severity of CHD (P>0.05). The power of the case-control study was determined to be 63.3%. In addition, the G allele frequency was calculated as 63.6% in the Han Chinese population, which was similar to the 59.3% recorded for the HapMap Chinese population of Han Chinese individuals living in Beijing, compared with 24.3% in European descendents (HapMap-CEU). Therefore, the results indicated that the IKZF2 rs12619285 polymorphism was not associated with CHD in a Han Chinese population. The discrepancy in the association between rs12619285 and CHD may be due to the ethnic differences between Han Chinese and European populations.

Associations between variants in IL-33/ST2 signaling pathway genes and coronary heart disease risk

The IL-33/ST2 signaling pathway plays an important role in coronary artery disease (CHD); however, few studies have explored how variants in IL-33/ST2 genes influence CHD risk. Here, we examined the association between genetic variants in IL-33, ST2, and IL-1RAcP of the IL-33/ST2 axis and the risk of CHD. We conducted a case-controlled study with 1146 CHD cases and 1146 age- and sex-frequency-matched controls. Twenty-eight single nucleotide polymorphisms (SNPs) in IL-33, ST2, and IL-1RAcP were genotyped by Sequenom MassArray and TaqMan assay. Logistic regression was used to analyze these associations. The SNP rs4624606 in IL-1RAcP was nominally associated with CHD risk. The AA genotype was associated with a 1.85-fold increased risk of CHD (95% confidence interval (CI) = 1.01-3.36; p = 0.045) compared to the TT genotype. Further analysis showed that AA carriers also had a higher risk of CHD than TT + TA carriers (odds ratio (OR) = 1.85; 95% CI = 1.85-3.35; p = 0.043). However, no significant association was observed between variants in IL-33/ST2 genes and CHD risk. Further studies are needed to replicate our results in other ethnic groups with larger sample size.

Meta-analyses of four eosinophil related gene variants in coronary heart disease

The goal of our study is to assess the contribution of four eosinophil related gene variants (rs12619285, rs1420101, rs3184504 and rs4143832) to the risk of coronary heart disease (CHD). We conducted four meta-analyses of studies examining the association between four eosinophil related gene variants and the risk of CHD. A systematic search was conducted using MEDLINE, EMBASE, Web of Science and China National Knowledge Infrastructure (CNKI), Wanfang Chinese Periodical. A case-control study was conducted between 162 CHD cases and 119 non-CHD controls to explore their contribution to CHD. For rs3184504 of SH2B3 gene, the meta-analysis was performed among 19 study stages among 94,555 participants. Significant association between rs3184504 and CHD risk was observed in European and South Asian populations (OR = 1.13, 95% CI = 1.10-1.16, p < 0.0001, fixed-effect method). For the other SNPs (rs12619285, rs1420101, and rs4143832), we combined our case-control data with the previous studies and found no association of them with the risk of CHD. No significant contribution of the four genetic variants to CHD was observed in Han Chinese (p > 0.05). In conclusion, our results supported a significant association between rs3184504 of SH2B3 gene and the risk of CHD in Europeans and South Asians, although we were unable to observe association between the four variants and the risk of CHD in Han Chinese.

Common genetic variation at the IL1RL1 locus regulates IL-33/ST2 signaling

The suppression of tumorigenicity 2/IL-33 (ST2/IL-33) pathway has been implicated in several immune and inflammatory diseases. ST2 is produced as 2 isoforms. The membrane-bound isoform (ST2L) induces an immune response when bound to its ligand, IL-33. The other isoform is a soluble protein (sST2) that is thought to be a decoy receptor for IL-33 signaling. Elevated sST2 levels in serum are associated with an increased risk for cardiovascular disease. We investigated the determinants of sST2 plasma concentrations in 2,991 Framingham Offspring Cohort participants. While clinical and environmental factors explained some variation in sST2 levels, much of the variation in sST2 production was driven by genetic factors. In a genome-wide association study (GWAS), multiple SNPs within IL1RL1 (the gene encoding ST2) demonstrated associations with sST2 concentrations. Five missense variants of IL1RL1 correlated with higher sST2 levels in the GWAS and mapped to the intracellular domain of ST2, which is absent in sST2. In a cell culture model, IL1RL1 missense variants increased sST2 expression by inducing IL-33 expression and enhancing IL-33 responsiveness (via ST2L). Our data suggest that genetic variation in IL1RL1 can result in increased levels of sST2 and alter immune and inflammatory signaling through the ST2/IL-33 pathway.

Toll-like receptors and human disease: lessons from single nucleotide polymorphisms

Toll-like receptors (TLRs), a large group of proteins which recognize various pathogen-associated molecular patterns, are critical for the normal function of the innate immune system. Following their discovery many single nucleotide polymorphisms within TLRs and components of their signaling machinery have been discovered and subsequently implicated in a wide range of human diseases including atherosclerosis, sepsis, asthma, and immunodeficiency. This review discusses the effect of genetic variation on TLR function and how they may precipitate disease.

Eosinophil adoptive transfer system to directly evaluate pulmonary eosinophil trafficking in vivo

Most in vivo studies of granulocytes draw conclusions about their trafficking based on examination of their steady-state tissue/blood levels, which result from a combination of tissue homing, survival, and egress, rather than direct examination of cellular trafficking. Herein, we developed a unique cell transfer system involving the adoptive transfer of a genetically labeled, bone-marrow-derived unique granulocyte population (eosinophils) into an elicited inflammatory site, the allergic lung. A dual polychromatic FACS-based biomarker-labeling system based on the IL4-eGFP transgene (4get) or Cd45.1 allele was used to track i.v. transferred eosinophils into the airway following allergen or T(H)2-associated stimuli in the lung in multiple mouse strains. The system was amenable to reverse tagging of recipients, thus allowing transfer of nonlabeled eosinophils and competitive tracking of multiple populations of eosinophils in vivo. The half-life of eosinophils in the blood was 3 h, and migration to the lung was dependent upon the dosage of transferred eosinophils, sensitive to pertussis toxin pretreatment, peaked at ∼24 h after adoptive transfer, and revealed a greater than 8-d eosinophil half-life in the lung. Eosinophil migration to the lung was dependent upon recipient IL-5 and IL-13 receptor α1 and donor eosinophil C-C chemokine receptor type 3 (CCR3) and interleukin 1 receptor-like 1 (ST2) in vivo. Taken together, this unique eosinophil transfer system provides an unprecedented opportunity to examine airway eosinophil migration without the need for extensive efforts to acquire donor source and time-consuming genetic crossing and has already been used to identify a long eosinophil half-life in the allergic lung and a definite role for ST2 in regulating eosinophil trafficking.

Recent research and developmental strategy of anti-asthma drugs

Extensive research over the past decade has provided information about the pharmacotherapy of bronchial asthma (BA). Anti-asthma drugs are classified into two categories: relievers (for the relief of asthma attack symptoms) and controllers (for the prevention of asthma symptoms). This paper aims to review the recent advancements of anti-asthma drugs that are controller medicines. The controllers mainly act on immune and inflammatory responses in BA development. 1) Immunomodulators. Drugs that act on the immune response are classified into two categories: immunosuppressors and immunomodulators, including immunopotentiators. The immunomodulation of the Th1 and Th2 imbalance is the first strategy of the controller because allergic BA is thought to be caused by Th2-polarized immunity. Suplatast is a novel immunomodulator that can adjust the imbalance in the Th1/Th2 immune response and shows clear clinical efficacy against BA. The immunomodulator approach has shifted from a more theoretical and conceptual model to one supported by evidence of clinical efficacy.2) Anti-inflammatory agents. Corticosteroids,mast cell stabilizers and autacoid inhibitors are anti-inflammatory agents for BA. The clinical superiority of the combined therapy of inhaled corticosteroids and long-acting beta2 agonists is evident. This combined therapy shows a potent synergic anti-inflammatory effect compared to the effect by corticosteroids alone. Currently, the anti-inflammatory agents for BA under development are drugs affecting lipid mediators. The prostaglandin (PG) D2 antagonist, PGE2, EP3 agonist and PGI2 agonist are being considered in addition to well-established leukotriene and thromboxane A2 inhibitors. New development strategies and therapeutics for controllers are described in this review.