Association of TNF haplotypes with asthma, serum IgE levels, and correlation with serum TNF-alpha levels

Transfluthrin is Associated with High Susceptibility to Asthma in Children with Promoter Variants of Beta Chain of High-Affinity Receptor IgE and Tumour Necrosis Factors-α Genes

This study investigates the genetic variations in FcεR1β-109 C/T (rs512555) and TNF-α-308 G/A (rs1800629) genes and examines whether the mosquito repellent transfluthrin (TFT) modifies the risk for asthmatic children. A case-control study was conducted involving 130 asthmatic children and 123 age-sex matched controls. Differential leukocyte counts, IgE, and hs-CRP levels were estimated using a five-part haematology analyzer and Beckman Coulter (AU480), respectively. Genetic variations in FcεR1β-109 and TNF-α-308 were analysed using restriction fragment length polymorphism. Serum TFT levels were measured using gas chromatography-tandem mass spectrometry. Asthmatic children had significantly increased total leukocyte, neutrophil, lymphocyte, eosinophil, and basophil counts (p < 0.0001), while their monocyte counts were lower compared to controls (p < 0.0001). TFT levels were higher in asthmatic children (1.38 ± 0.91 vs. control 0.69 ± 0.41µg/L, p < 0.0001), which predominantly induced wheezing. Elevated TFT levels were associated with an increased risk of childhood asthma (OR: 3.08, p < 0.0001). Children with the FcεRIβ TT (OR: 2.39, p < 0.017) and TNF-α GG genotypes (OR: 7.17, p < 0.0001) were more susceptible to asthma. TFT synergistically enhanced the risk of asthma in both FcεRIβ-109 TT (OR: 5.3, p = 0.001) and TNF-α-308 GG (OR: 17.18, p < 0.0001) genotypes. TFT levels were correlated with IgE (r = 0.363; p = 0.006), hs-CRP (r = 0.324; p = 0.049) and eosinophil (r = 0.300; p = 0.038), respectively. IgE and eosinophils were correlated (r = 0.599, p = 0.001) in the FcεRIβ TT genotype-carrying asthmatic children. Similarly, neutrophils and hs-CRP were correlated (r = 0.768, p < 0.0001) in asthmatic children with TNF-α GG genotype. The risk of asthma is inherently higher in children with FcεRIβ TT and TNF-α GG variants. TFT exposure amplifies the risk of asthma in children among all the subgenotypes of both genes. TFT influences IgE and eosinophil in FcεRIβ TT genotype while it influences neutrophils and hs-CRP in TNF-α GG genotypes.

Biomarkers of asthma relapse and lung function decline in adults with spontaneous asthma remission: A population-based cohort study

BACKGROUND

The extent to which biomarkers of asthma activity persist in spontaneous asthma remission and whether such markers are associated with future respiratory outcomes remained unclear. We investigated the association between sub-clinical inflammation in adults with spontaneous asthma remission and future asthma relapse and lung function decline.

METHODS

The Tasmanian Longitudinal Health Study is a population-based cohort (n = 8583). Biomarkers of systemic inflammation were measured on participants at age 45, and latent profile analysis was used to identify cytokine profiles. Bronchial hyperresponsiveness (BHR) and nitric oxide products in exhaled breath condensate (EBC NOx) were measured at age 50. Participants with spontaneous asthma remission at ages 45 (n = 466) and 50 (n = 318) were re-evaluated at age 53, and associations between baseline inflammatory biomarkers and subsequent asthma relapse and lung function decline were assessed.

RESULTS

We identified three cytokine profiles in adults with spontaneous asthma remission: average (34%), Th2-high (42%) and Th2-low (24%). Compared to the average profile, a Th2-high profile was associated with accelerated decline in post-BD FEV1 /FVC (MD -0.18% predicted per-year; 95% CI -0.33, -0.02), while a Th2-low profile was associated with accelerated decline in both post-BD FEV1 (-0.41%; -0.75, -0.06) and post-BD FVC (-0.31%; -0.62, 0.01). BHR and high TNF-α during spontaneous remission were associated with an increased risk of asthma relapse. In contrast, we found no evidence of association between EBC NOx and either asthma relapse or lung function decline.

CONCLUSION

BHR and serum inflammatory cytokines have prognostic value in adults with spontaneous asthma remission. At-risk individuals with BHR, Th2-high or Th2-low cytokine profiles may benefit from closer monitoring and on-going follow-up.

A review on aero-allergen induced allergy in India

Allergic diseases such as bronchial asthma, rhinitis and eczema are an important public health issue globally in 21st century. Their prevalence and impact in India is high, in terms of total numbers of people affected. Due to diverse climate and lifestyle, the Indian population is exposed to a rich and varied range of aerobiological particles. In the last two decades in India, 83 pollens, 34 fungi, six dust mite and 19 insect species were reported as allergenic, often contributing to heavy allergenic exposure in indoor and outdoor environments. There are currently few practitioners who offer allergy diagnosis and treatment in India, but there is active basic and molecular research aiming to improve the health of allergic patients. This review explores the field of aero-allergy in India during the last two decades, with special emphasis on prevalence across various centres and relevant scientific advances such as genetic associations and new therapeutics. This review will be helpful for clinicians to select aero-allergens for sensitisation testing in patients suffering from symptoms in different regions of India, and to support patients undertaking prophylaxis of allergic symptoms in India according to local environmental conditions. This study also helps to define patient selection for allergy testing and the role of test results in guiding allergic disease management in the Indian context. Finally, we summarize genetic findings relevant to aero-allergy in India and discuss the development of novel therapeutics for investigation and management of aero-allergy in India.

Quantitative and causal analysis for inflammatory genes and the risk of Parkinson's disease

Background

The dysfunction of immune system and inflammation contribute to the Parkinson's disease (PD) pathogenesis. Cytokines, oxidative stress, neurotoxin and metabolism associated enzymes participate in neuroinflammation in PD and the genes involved in them have been reported to be associated with the risk of PD. In our study, we performed a quantitative and causal analysis of the relationship between inflammatory genes and PD risk.

Methods

Standard process was performed for quantitative analysis. Allele model (AM) was used as primary outcome analysis and dominant model (DM) and recessive model (RM) were applied to do the secondary analysis. Then, for those genes significantly associated with the risk of PD, we used the published GWAS summary statistics for Mendelian Randomization (MR) to test the causal analysis between them.

Results

We included 36 variants in 18 genes for final pooled analysis. As a result, IL-6 rs1800795, TNF-α rs1799964, PON1 rs854560, CYP2D6 rs3892097, HLA-DRB rs660895, BST1 rs11931532, CCDC62 rs12817488 polymorphisms were associated with the risk of PD statistically with the ORs ranged from 0.66 to 3.19 while variants in IL-1α, IL-1β, IL-10, MnSOD, NFE2L2, CYP2E1, NOS1, NAT2, ABCB1, HFE and MTHFR were not related to the risk of PD. Besides, we observed that increasing ADP-ribosyl cyclase (coded by BST1) had causal effect on higher PD risk (OR[95%CI] =1.16[1.10-1.22]) while PON1(coded by PON1) shown probably protective effect on PD risk (OR[95%CI] =0.81[0.66-0.99]).

Conclusion

Several polymorphisms from inflammatory genes of IL-6, TNF-α, PON1, CYP2D6, HLA-DRB, BST1, CCDC62 were statistically associated with the susceptibility of PD, and with evidence of causal relationships for ADP-ribosyl cyclase and PON1 on PD risk, which may help understand the mechanisms and pathways underlying PD pathogenesis.

MUC7 VNTR polymorphism and association with bronchial asthma in Egyptian children

Overproduction of mucins in the airways donates largely to airway blockage in asthma patients. Glycoprotein MUC7 plays a role in the clearance of bacteria and has anti-candidacidal criteria. Our goal was to investigate the association between the MUC7 variable number of tandem repeats (VNTR) polymorphism and bronchial asthma among Egyptian children. The MUC7 VNTR polymorphism was investigated among 100 children with bronchial asthma and 100 healthy controls using polymerase chain reaction (PCR) method. Serum levels of immunoglobulin E (IgE), tumor necrosis factor-alpha (TNF-α), and transforming growth factor-beta1 (TGF-β1) were assessed by enzyme-linked immunosorbent assay (ELISA) technique. The frequencies of 6*5 genotype, 5*5 genotype, (6*5 + 5*5) genotypes, and MUC7*5 allele of the MUC7 VNTR variant were significantly lower among asthmatic patients than controls (p < 0.015, OR = 0.39, 95% CI = 0.19-0.81; p = 0.03, OR = 0.18, 95% CI = 0.04-0.86; p < 0.001, OR = 0.29, 95% CI = 0.15-0.58; p < 0.001, OR = 0.3, 95% CI = 0.17-0.55, respectively). The (6*5 + 5*5) genotypes of the MUC7 VNTR variant were not associated with the clinical manifestations and serum levels of IgE, TNF-α, and TGF-β1 among asthmatic patients (p ˃ 0.05). In conclusion, the (6*5 + 5*5) genotypes of the MUC7 VNTR variant may have a protective role for bronchial asthma in Egyptian children.

Neuroscience and treatment of asthma, new therapeutic strategies and future aspects

AIMS

Asthma is an airway inflammatory disease that is affected by neurological and psychological factors. The aim of present review is to investigating the relationship between neural functions and neurobiological changes and asthma symptoms.

MAIN METHODS

The information in this article is provided from articles published in English and reputable database using appropriate keywords from 1970 to October 2020.

KEY FINDINGS

The symptoms of asthma such as cough, difficult breathing, and mucus secretion get worse when a person is suffering from stress, anxiety, and depression. The function of the insula, anterior cingulate cortex, and hypothalamic-pituitary-adrenal axis changes in response to stress and psychological disease; then the stress hormones are produced from neuroendocrine system, which leads to asthma exacerbation. The evidence represents that psychological therapies or neurological rehabilitation reduces the inflammation through modulating the activity of neurocircuitry and the function of brain centers involved in asthma. Moreover, the neurotrophins and neuropeptides are the key mediators in the neuro-immune interactions, which secrete from the airway nerves in response to brain signals, and they could be the target of many new therapies in asthma.

SIGNIFICANCE

This review provides an insight into the vital role of the central and peripheral nervous system in development and exacerbation of asthma and provides practical approaches and strategies on neural networks to improve the airway inflammation and asthma severity.

Inflammatory phenotype modulation in the respiratory tract and systemic circulation of e-cigarette users: a pilot study

Over 40 million people use e-cigarettes worldwide, but the impact of chronic e-cigarette use on health has not been adequately defined. In particular, effects of e-cigarette aerosol inhalation on inflammation and host defenses across the body are not fully understood. We conducted a longitudinal cohort pilot study to explore changes in the inflammatory state and monocyte function of e-cigarette users (n=20) versus healthy controls (n=13), and to evaluate effects of e-cigarette use reduction on the same. Saliva, sputum, and blood were obtained from e-cigarette users at baseline and after a 2-week intervention of decreased e-cigarette use. Overall, across 38 proteins quantified by multiplex, airway samples from e-cigarette users tended to have decreased levels of immunomodulatory proteins relative to healthy controls, while levels of cytokines, chemokines and growth factors in the circulation tended to be elevated. Specifically, e-cigarette users had lower levels of IL-1 receptor antagonist (IL-1Ra) in saliva (p<0.0001), with higher IL-1Ra and GRO levels in sputum (p<0.01 and p<0.05, respectively), and higher levels of both TNFβ (p<0.0001) and VEGF (p<0.0001) in plasma. Circulating monocytes from e-cigarette users had alterations in their inflammatory phenotype in response to reduced e-cigarette use, with blunted IL-8 and IL-6 release upon challenge with bacterial lipopolysaccharide (p<0.001 and p<0.05, respectively), suggesting a decreased ability to appropriately respond to bacterial infection. Based on these findings, chronic inhalation of e-cigarette aerosols alters the inflammatory state of the airways and systemic circulation, raising concern for the development of both inflammatory and infectious diseases in chronic users of e-cigarettes.

Effects of tumor necrosis factor (TNF) gene polymorphisms on the association between smoking and lung function among workers in swine operations

Workers in swine operations may be at increased risk of developing respiratory problems. These respiratory conditions are more prevalent among workers who are smokers. Tumor necrosis factor (TNF) genes play an important role in human immune responses to various respiratory hazards. This study aimed to investigate whether polymorphisms in TNF genes might alter the effects of smoking on lung function among workers in swine operations. Three hundred and seventy-four full-time workers from large swine operations and 411 non-farming rural dwellers in Saskatchewan were included in this study. Information on demographic and lifestyle characteristics, pulmonary function, and blood samples were obtained. Multiple linear regression analyses were used in the statistical analysis. Three promoter polymorphisms (rs1799724, rs361525, and rs1800629) in the TNF gene were investigated. Only the interaction term between smoking status and rs1799724 was significant in the multiple regression models. Among workers with the rs1799724 polymorphism (TT+TC), current smokers exhibited significantly lower lung function than nonsmokers. These associations were not observed among workers with the wild-type (CC). These findings were not observed among non-farming rural dwellers. Data demonstrated the possible involvement of TNF gene in (1) development of adverse respiratory conditions among workers who are smokers, (2) importance of smoking cessation among workers, especially those with polymorphisms in the TNF gene, and (3) potential implications in treatment, screening, and prevention.

Advances in asthma genetics

While asthma has a strong genetic component, our current ability to systematically understand and predict asthma risk remains low, despite over a hundred genetic associations. The reasons for this unfilled gap range from technical limitations of current approaches to fundamental deficiencies in the way we understand asthma. These are discussed in the context of genomic advances.

Effects of the IL6 -174G>C promoter polymorphism and IL-6 serum levels on the progression of cutaneous malignant melanoma

Cutaneous malignant melanoma (CMM) is one of the most immunogenic types of cancer, with a 6-fold higher rate of spontaneous regression than any other malignancy. In addition to responsiveness to different immunotherapies, the immunogenicity of CMM highlights the important role of the host immune system in the response to CMM. The present study aimed to explore the role of two functional promoter polymorphisms [IL6 -174G>C (rs1800785) and TNFA -308G>A (rs1800629)] in the regulation of the genes encoding the pro-inflammatory cytokines interleukin (IL)-6 and tumor necrosis factor-α, specifically in patients with CMM. A total of 76 patients with CMM and 200 control subjects were genotyped using PCR-restriction fragment length polymorphism. The genotype frequencies for both single nucleotide polymorphisms (SNPs) did not differ significantly between the patients and controls (P=0.358 and P=0.810 for IL6 and TNFA, respectively). However, compared with carriers of C-allele genotypes (CG+CC), patients with the IL6 -174GG genotype exhibited more advanced melanoma (Clark scale ≥3; P=0.037) and shorter survival times, particularly those who worked outdoors (in conditions with increased sunlight exposure; P=0.016). Furthermore, the serum IL-6 levels of patients with CMM were significantly higher than those of the control subjects, which were associated with unfavorable blood and serum characteristics and tumor progression (development of new distant metastases; P=0.004), and with a shorter overall survival time (P=0.042). Using a Cox proportional hazard model, the IL6 -174GG genotype was found to be an independent prognostic factor for reduced survival time (P=0.030), together with sex (being male; P=0.004) and occupations with higher exposure to sunlight (P=0.047). In conclusion, the results of the present study indicated that the promoter polymorphisms IL6 -174G>C and TNFA -308G>A are not predisposing factors for CMM. However, the IL6 -174G>C SNP and IL-6 serum concentrations are likely to influence the progression of the disease, and the GG genotype and higher IL-6 serum levels may indicate shorter survival.

The Association of Serum TNF-α Levels and Blood Multi-Elements Modified by TNF-α Gene Polymorphisms in Metal Industrial Workers

Health of the metal industrial workers should be a noteworthy issue due to the hazard of chronic exposure to metals or toxic elements. The interactions among multiple elements are sophisticated and may differ from person to person. Tumor necrosis factor-α (TNF-α) gene polymorphisms were supposed to be involved with the interactions because TNF-α plays an important role in inflammation, a mechanism by which toxic elements cause threats to human health. This research aimed to analyze the influence of TNF-α gene polymorphisms and multi-elements on serum TNF-α level. Blood multi-elements concentrations (lead, cadmium, arsenic, selenium, cobalt, copper, and zinc), serum TNF-α level, and TNF-α single nucleotide polymorphisms (SNPs), including −238G > A (rs361525), −308G > A (rs1800629), −857C > T (rs1799724), −863C > A (rs1800630), and −1031T > C (rs1799964), were measured in 462 metal industrial workers. We applied mixed-effect models to analyze the interactions among multi-elements and TNF-α SNPs. Blood concentration of all elements were positively associated with serum TNF-α level, and the effects may be modified by TNF-α gene polymorphisms. Our study revealed that TNF-α −308A/A and −1031C/C may be susceptible genotypes, and thus we suggest that those workers should take preventive measures against metal toxicity.

Promoter Polymorphism (-308G/A) of Tumor Necrosis Factor-Alpha (TNF-α) Gene and Asthma Risk: An Updated Meta-Analysis

Background and Aims: The relationship between the promoter polymorphism (-308G/A) of the tumor necrosis factor-alpha (TNF-α) gene and the susceptibility to asthma has been tested in several studies. However, the results have been inconsistent. Therefore, we performed an updated meta-analysis to evaluate the relationship between this promoter polymorphism of the TNF-α gene and the risk of asthma. Methods: Fifty case-control studies were included in this meta-analysis which provided 17,937 controls and 9961 asthma patients. The pooled p-value, odds ratio (OR), and 95% confidence interval (95% CI) were used to investigate the strength of the association of this polymorphism of the TNF-α gene with the risk of asthma. The meta-analysis was carried out by Comprehensive Meta-Analysis software. Results: The results of our meta-analysis revealed that the TNF-α polymorphism (-308, G/A) was strongly associated with the risk of asthma (p < 0.05 in the allelic, dominant, and recessive models, respectively). In further analyses, based on age group and ethnicity, we observed this association for all subpopulations examined (p < 0.05 in allelic, dominant, and recessive models, respectively). Conclusion: This large-scale meta-analysis supports a strong association between the TNF-α gene promoter polymorphism (-308G/A) and the development to asthma in both children and adults.

Associations of tumor necrosis factor-α polymorphisms with the risk of asthma: a meta-analysis

OBJECTIVE

Recently, potential correlations between tumor necrosis factor-α (TNF-α) polymorphisms and asthma were investigated by some pilot studies, but the results of these studies were inconsistent. Therefore, we performed this meta-analysis to better evaluate the relationship between TNF-α polymorphisms and the risk of asthma.

METHODS

Eligible studies were searched in PubMed, Medline, Embase and CNKI. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to assess correlations between TNF-α polymorphisms and asthma.

RESULTS

A total of 50 studies were included for analyses. Significant associations with the risk of asthma were detected for TNF-α - 238 G/A, -308 G/A and - 857C/T polymorphisms in overall analyses. Further subgroup analyses according to ethnicity of participants revealed that TNF-α - 238 G/A polymorphism was significantly correlated with the risk of asthma in Caucasians, TNF-α - 308 G/A polymorphism was significantly correlated with the risk of asthma in West Asians, TNF-α - 857C/T polymorphism was significantly correlated with the risk of asthma in Caucasians, TNF-α - 863C/A polymorphism was significantly correlated with the risk of asthma in East Asians, and TNF-α - 1031 T/C polymorphism was significantly correlated with the risk of asthma in Caucasians and East Asians.

CONCLUSIONS

Our findings indicated that TNF-α - 238 G/A, -308 G/A, -857C/T, -863C/A and - 1031 T/C polymorphisms may serve as potential biological markers for asthma in certain ethnicities.

Relationship between TNF-α -1031T/C gene polymorphism, plasma level of TNF-α, and risk of cachexia in head and neck cancer patients

Background

Malnutrition and cachexia are frequent among head and neck cancer (HNC) patients and these syndromes are associated with both poor quality of life and unfavorable disease prognosis. Unfortunately, there are still no established biomarkers that could predict the development of cachexia. Among potential molecular alterations related to cancer cachexia, there are single-nucleotide polymorphisms (SNPs) within genes encoding pro-inflammatory cytokines such as TNF-α.

The aim of the study

To investigate TNF-α −1031T/C SNP as a risk factor of cachexia in 62 HNC patients subjected to radiotherapy. DNA was isolated from whole blood samples and genotyping was conducted using real-time PCR method by means of TaqMan SNP Genotyping Assay. TNF-alpha Human ELISA Kit was used to determine TNF-α concentration in each extracted plasma sample. Moreover, the relationship between genotype variants of TNF-α and plasma level of TNF-α was examined. Detailed clinical–demographic and nutritional data were collected from each study participant.

Results

CC genotype carriers were at a significantly higher risk of being qualified as cachectic compared with other genotype carriers (p = 0.044; HR = 3.724). Subjects, who carried CC genotype had significantly lower body mass compared to patients with TT and CT genotype (p = 0.045). Moreover, CC individuals had the highest TNF-α plasma level (median 10.70 ± 0.72 pg/mL, p = 0.006) among the studied cases. We also noted, that CC genotype carriers had significantly higher risk of early death incidence compared to other genotype carriers [overall survival (OS): 28 vs 38 months (HR = 3.630, p = 0.013)].

Conclusion

Despite the differences between SGA and NRS scoring, the presence of CC genotype could be a useful objective marker allowing for the prediction of cachexia development in both parenterally nourished and non-parenterally nourished patients. Patients with CC genotype had also the highest risk of early death incidence; therefore, such individuals should be qualified for parenteral nutrition and supportive care at the time of diagnosis to improve further therapy outcomes. Moreover, this is the first study demonstrating the relationship between TNF-α −1031T/C polymorphism and plasma level of TNF-α. This is also the first paper investigating the role of TNF-α −1031T/C in cancer cachexia.

Modulation of the IL-23/IL-17 axis by fenofibrate ameliorates the ovalbumin/lipopolysaccharide-induced airway inflammation and bronchial asthma in rats

The overlapping between asthmatic subtypes, including both CD4+ T helper (TH)2 and TH17 cells, is found in the natural course of allergic asthma, especially in exacerbations and severe and insensitive forms to steroids, which are in need of new molecular therapies. In the TH2-subset mediated asthma, fenofibrate displays therapeutic promises, besides evidenced therapeutic effects on TH17-mediated colitis and myocarditis. Therefore, the effects of fenofibrate versus dexamethasone on IL-23/IL-17 axis in ovalbumin (OVA)/lipopolysaccharide (LPS)-induced airway inflammation and bronchial asthma in rats were explored. The OVA/LPS sensitization and challenge were performed for 28 days in male Wistar rats. After sensitization, fenofibrate (100 mg/kg/day) or dexamethasone (2.5 mg/kg/day) was orally administered from the day 15 to 28. Either fenofibrate or dexamethasone attenuated the severity of OVA/LPS-induced airway inflammation and bronchial asthma through significant ameliorations in the total serum immunoglobulin (Ig)E assay; the total and differential leukocytic counts in the bronchoalveolar lavage (BAL) fluid; the lung inflammatory cytokines such as interleukin (IL)-4, IL-13, IL-17, and IL-23, transforming growth factor (TGF)-β₁, and tumor necrosis factor(TNF)-α levels; and the lung IL-17 and IL-23 expressions. In addition to the reduction in the inflammatory and fibrotic histopathological scores, fenofibrate significantly ameliorated the BAL neutrophilic count and the lung IL-17 and IL-23 expressions in comparison to dexamethasone. The suppression of IL-23/IL-17 axis could be considered a molecular therapeutic target for fenofibrate in OVA/LPS-induced airway inflammation and bronchial asthma. Combined therapeutic regimens of fenofibrate and steroids should be furtherly investigated in severe and resistant asthma.

Association of TNF-α Gene Polymorphisms with Production of Protein and Susceptibility to Chronic Hepatitis B Infection in the South East Iranian Population

BACKGROUND

The host genetic background regulates the natural history of chronic hepatitis B virus (HBV) infection.

OBJECTIVES

The aim of this study was to investigate the association between TNF-α gene polymorphism in the promoter region and susceptibility to chronic hepatitis B virus infection.

METHODS

Four polymorphisms of TNF-α gene including -238 A/G, -308 A/G, -857 C/T, and -863 A/C were analyzed by PCR-RFLP in 100 chronic HBV infected patients (HBV group), 40 spontaneously recovered HBV subjects (SR group), and 100 healthy controls (C group). Also, serum levels of protein were monitored.

RESULTS

The study showed that the existence of -308 G, -857 C, and -863 A alleles significantly increased susceptibility to chronic HBV infection. In addition, GGCA haplotype had a higher frequency in HBV patients than C and SR groups that might be related to the natural history of the infection. Chronic HBV patients with -308 GG, -857 CC, and -863 AA genotypes had lower serum levels of TNF-α compared to those with other genotypes.

CONCLUSIONS

The results indicated that there was a positive association between susceptibility to chronic HBV infection and TNF-α polymorphism. In addition, HBV patients carrying -308 GG, -857 CC, and -863 AA genotypes with lower serum levels of TNF-α had an increased risk of infection.

Genetic, Immune-Inflammatory, and Oxidative Stress Biomarkers as Predictors for Disability and Disease Progression in Multiple Sclerosis

The aim of this study was to evaluate the TNFβ NcoI polymorphism (rs909253) and immune-inflammatory, oxidative, and nitrosative stress (IO&NS) biomarkers as predictors of disease progression in multiple sclerosis (MS). We included 212 MS patients (150 female, 62 male, mean (±standard deviation (SD)) age = 42.7 ± 13.8 years) and 249 healthy controls (177 female, 72 male, 36.8 ± 11 years). The disability was measured the Expanded Disability Status Scale (EDSS) in 2006 and 2011. We determined the TNFβ NcoI polymorphism and serum levels of interleukin (IL)-6, tumor necrosis factor (TNF)-α, interferon (IFN)-γ, IL-4, IL-10, and IL-17, albumin, ferritin, and plasma levels of lipid hydroperoxides (CL-LOOH), carbonyl protein, advanced oxidation protein products (AOPPs), nitric oxide metabolites (NOx), and total radical-trapping antioxidant parameter (TRAP). The mean EDSS (±SD) in 2006 was 1.62 ± 2.01 and in 2011 3.16 ± 2.29, and disease duration was 7.34 ± 7.0 years. IL-10, TNF-α, IFN-γ, AOPP, and NOx levels were significantly higher and IL-4 lower in MS patients with a higher 2011 EDSS scores (≥3) as compared with those with EDSS < 3. The actual increases in EDSS from 2006 to 2011 were positively associated with TNF-α and IFN-γ. Increased IFN-γ values were associated with higher pyramidal symptoms and increased IL-6 with sensitive symptoms. Increased carbonyl protein and IL-10 but lowered albumin levels predicted cerebellar symptoms. The TNFB1/B2 genotype decreased risk towards progression of pyramidal symptoms. Treatments with IFN-β and glatiramer acetate significantly reduced TNF-α but did not affect the other IO&NS biomarkers or disease progression. Taken together, IO&NS biomarkers and NcoI TNFβ genotypes predict high disability in MS and are associated with different aspects of disease progression. New drugs to treat MS should also target oxidative stress pathways.

Inflammation-related cytokine gene polymorphisms in Behçet's disease

Behçet's disease (BD) is a complex, multisystemic inflammatory disorder of unclear etiology. Single nucleotide polymorphisms in tumor necrosis factor (TNF) and interleukin (IL)-10 genes have been implicated in susceptibility to BD with inconsistent results in several ethnic populations. The aim of this case-control study was to evaluate the association of TNF-α (-308G/A), TNF-β (+252A/G), and IL-10 (-1082G/A, -819C/T, and -592 C/A) polymorphisms with susceptibility of BD in Saudi patients. Molecular genotyping of TNF-α, TNF-β, and IL-10 gene polymorphisms was performed to analyze the alleles and genotypes distribution in 272 Saudi subjects, including BD patients (61) and healthy controls (211). The frequencies of allele A and genotype GA of TNF-α (-308G/A) were significantly higher, whereas those of allele G and genotypes GG were significantly lower in BD patients than controls, indicating that A allele and GA genotype are susceptible, while G allele and GG genotype may be refractory to BD. The distribution of frequencies of alleles and genotype of TNF-β (+252A/G) promoter polymorphism was not significantly different between BD patients and healthy controls. Genotypes 1082GG, -819TT, and 592AA of IL-10 polymorphisms are significantly associated with susceptibility risk of BD, while genotypes 1082AA, 1082GA, 819CC, 819CT, 592CC, and 592CA are resistant to BD. This study indicates that TNF-α (-308G/A) and IL-10 (-1082G/A, -819C/T, and -592C/A) polymorphisms are associated with risk of BD susceptibility in Saudi patients. However, larger scale studies in Saudi population as well as in other ethnicities are needed to confirm this association.

Genetic variants in TNFα, TGFB1, PTGS1 and PTGS2 genes are associated with diisocyanate-induced asthma

Diisocyanates are the most common cause of occupational asthma, but risk factors are not well defined. A case-control study was conducted to investigate whether genetic variants in inflammatory response genes (TNFα, IL1α, IL1β, IL1RN, IL10, TGFB1, ADAM33, ALOX-5, PTGS1, PTGS2 and NAG-1/GDF15) are associated with increased susceptibility to diisocyanate asthma (DA). These genes were selected based on their role in asthmatic inflammatory processes and previously reported associations with asthma phenotypes. The main study population consisted of 237 Caucasian French Canadians from among a larger sample of 280 diisocyanate-exposed workers in two groups: workers with specific inhalation challenge (SIC) confirmed DA (DA(+), n = 95) and asymptomatic exposed workers (AW, n = 142). Genotyping was performed on genomic DNA, using a 5' nuclease PCR assay. After adjusting for potentially confounding variables of age, smoking status and duration of exposure, the PTGS1 rs5788 and TGFB1 rs1800469 single nucleotide polymorphisms (SNP) showed a protective effect under a dominant model (OR = 0.38; 95% CI = 0.17, 0.89 and OR = 0.38; 95% CI = 0.18, 0.74, respectively) while the TNFα rs1800629 SNP was associated with an increased risk of DA (OR = 2.08; 95% CI = 1.03, 4.17). Additionally, the PTGS2 rs20417 variant showed an association with increased risk of DA in a recessive genetic model (OR = 6.40; 95% CI = 1.06, 38.75). These results suggest that genetic variations in TNFα, TGFB1, PTGS1 and PTGS2 genes contribute to DA susceptibility.

Genetic basis of interindividual susceptibility to cancer cachexia: selection of potential candidate gene polymorphisms for association studies

Cancer cachexia is a complex and multifactorial disease. Evolving definitions highlight the fact that a diverse range of biological processes contribute to cancer cachexia. Part of the variation in who will and who will not develop cancer cachexia may be genetically determined. As new definitions, classifications and biological targets continue to evolve, there is a need for reappraisal of the literature for future candidate association studies. This review summarizes genes identified or implicated as well as putative candidate genes contributing to cachexia, identified through diverse technology platforms and model systems to further guide association studies. A systematic search covering 1986-2012 was performed for potential candidate genes / genetic polymorphisms relating to cancer cachexia. All candidate genes were reviewed for functional polymorphisms or clinically significant polymorphisms associated with cachexia using the OMIM and GeneRIF databases. Pathway analysis software was used to reveal possible network associations between genes. Functionality of SNPs/genes was explored based on published literature, algorithms for detecting putative deleterious SNPs and interrogating the database for expression of quantitative trait loci (eQTLs). A total of 154 genes associated with cancer cachexia were identified and explored for functional polymorphisms. Of these 154 genes, 119 had a combined total of 281 polymorphisms with functional and/or clinical significance in terms of cachexia associated with them. Of these, 80 polymorphisms (in 51 genes) were replicated in more than one study with 24 polymorphisms found to influence two or more hallmarks of cachexia (i.e., inflammation, loss of fat mass and/or lean mass and reduced survival). Selection of candidate genes and polymorphisms is a key element of multigene study design. The present study provides a contemporary basis to select genes and/or polymorphisms for further association studies in cancer cachexia, and to develop their potential as susceptibility biomarkers of cachexia.

Lipopolysaccharide (LPS) exposure differently affects allergic asthma exacerbations and its amelioration by intranasal curcumin in mice

AIM

Lipopolysaccharide (LPS) is ubiquitous in the environment and can therefore, exacerbate allergic responses. Studies have suggested immunoregulatory effects of LPS according to route, dose and stage of exposure. Present study has examined whether dose and stage of LPS exposure (during sensitization and challenge with OVA) exacerbates airway inflammations, antigen specific-IgE level, histamine release, Th1/Th2 cytokine response. Further, anti-asthmatic potential of curcumin, through intranasal route has been evaluated for the first time in LPS induced airway inflammation in an ovalbumin (OVA)-challenged mouse asthma model.

METHODS

Balb/c mice were first sensitized with OVA on 1st and 8th day and exposed to two LPS doses (0.1/1.0 μg) separately on 2nd day and then further exposed to LPS with OVA-aerosol (from 9 to 14 day). Further, lower LPS dose (0.1 μg) was chosen for OVA exposed mouse model of asthma exacerbation study. Intranasal curcumin was administered from 9th to 14th day before every LPS exposure.

RESULTS

Exposure to LPS (0.1 μg) exacerbates airway inflammations in terms of IgE level, Th2-cytokine response (IL-4 and IL-5), histamine release, EPO and MPO activities and oxidative stress. Intranasal curcumin has effectively ameliorated airway exacerbations whereas dexamethasone, a known glucocorticosteroid, was not promising as compared to intranasal curcumin.

CONCLUSION

Schedule and dose of LPS exposure determines asthma exacerbations and intranasal curcumin could be better immunomodulatory agent in LPS exposed asthma exacerbations.

Association of tumor necrosis factor (TNF) promoter polymorphisms with plasma TNF-α levels and susceptibility to diabetic nephropathy in North Indian population

AIM

The concept of diabetic nephropathy (DN) as a metabolic disease is now being replaced by chronic low-grade inflammatory disease. Tumor necrosis factor-alpha (TNF-α) is a proinflammatory cytokine which plays an important role in the pathogenesis and clinical outcome of DN. Therefore, this work was planned to evaluate the association of -863C/A (rs1800630) and -1031T/C (rs1799964) polymorphisms in TNF gene with plasma TNF-α levels and DN among subjects with type 2 diabetes (T2DM) in a population from North India.

METHODS

Age and sex matched 100 healthy controls (HC), 100 T2DM subjects without nephropathy (DM) and 100 subjects with DN were screened for above polymorphisms using the PCR-RFLP methods. Plasma TNF-α levels were measured by ELISA. Analysis of variance and logistic regression were used to associate individual polymorphisms with plasma TNF-α levels and DN.

RESULTS

The allelic frequencies of -863C/A were 0.86/0.14 in HC, 0.72/0.23 in DM and 0.84/0.16 in DN, and that of -1031T/C were 0.89/0.11 in HC, 0.95/0.05 in DM and 0.80/0.20 in DN. The carriers of -863A allele had significantly lower plasma TNF-α levels (p<0.05). The -863C/A (OR=0.439, 95% CI=0.244-0.789, p=0.006) and -1031T/C (OR=3.0, 95% CI=1.355-6.642, p=0.007) were strongly associated with risk of development of DN.

CONCLUSIONS

-863C/A was associated with low whereas -1031T/C with high TNF-α levels. The, results suggest that -863C/A polymorphism might be protective whereas -1031T/C may be associated with increased risk for DN in subjects with T2DM from North India.

Association of TNF -1031 C/C as a potential protection marker for leprosy development in Amazonas state patients, Brazil

Polymorphisms present in the TNF promoter region has shown to influence the gene transcription. Leprosy displays different clinical manifestations according to the immune responses of the individual infected with Mycobacterium leprae. In this study, we evaluated the single nucleotide polymorphisms (SNPs) -238 G/A (rs361525), -308 G/A (rs1800629), -857 C/T (rs1799724), -863 A/C (rs1800630) and -1031 T/C (rs1799964) in the promoter region of the TNF to see whether these SNPs influence host-susceptibility to leprosy and the different clinical manifestation. Nucleotide sequencing was performed with DNA samples from 108 leprosy patients and 253 control subjects. An association between -1031 C/C genotype and protection from leprosy was observed when leprosy patients were compared to controls (OR 0.11; 95% CI=0.01-0.82; p=0.012). The -857 C/T genotype may be associated with susceptibility to leprosy (OR=1.81; 95% CI=1.09-3.00; p=0.028). Similar genotype and allele frequencies for the SNPs -308 G/A and -238 G/A were observed between leprosy patients and control subjects. Altogether, TNF polymorphisms in the promoter region may be predictive of leprosy outcome.

Variations in the TNFα gene and their interactions with the IL4R and IL10 genes in relation to hand osteoarthritis

Background

The development of osteoarthritis (OA) involves inflammation, but the evidence for participation of genes propagating or inhibiting inflammation in the OA process is inconsistent. We investigated the associations of common variants in the TNFα gene, and their interactions with other cytokine genes, with hand OA among Finnish women.

Methods

This cross-sectional study was based on bilateral hand radiographs of 542 female dentists and teachers which were classified according to the presence of OA (radiographic K-L score ≥ 2 in ≥ 3 joints) using reference images. The genotypes were determined by PCR-based methods. The degree of pairwise linkage disequilibrium (LD) and haplotypes were constructed and analyzed by the SNPStats software. The associations between four TNFα SNPs and hand OA were tested using logistic regression adjusting for age, occupation, and BMI, and fitting a log-additive model of inheritance. Gene-gene interactions of TNFα SNPs with IL4R and IL10 SNPs were examined by stratified logistic regression analyses. Possible interactions of the TNFα SNPs with variants in the previously reported IL1β and IL6 genes in influencing hand OA were also explored.

Results

Two TNFα polymorphisms (“-1031” and “-863”) were associated with hand OA (OR = 1.45, 95% CI 1.01-2.07 and 1.55, 1.06-2.25, respectively). These associations retained when adjusting further for IL1β “3954” and IL6 “174”. The TNFα G-A-G haplotype was associated with an increased risk of hand OA (1.61, 1.10-2.37, p = 0.01). Interactions were observed between TNFα “-1031” and IL4R Ser503Pro, TNFα “-1031” and IL10 “-1082”, and TNFα “-863” and IL10 “-1082” SNPs with regard to hand OA (p = 0.012, p = 0.0068, and p = 0.02, respectively). The carriage of the TNFα “-1031” minor allele doubled the risk (2.01, 1.26 - 3.22) only in women with the IL4R Ser/Ser genotype. Similarly, the TNFα “-1031” and “-863” minor alleles were associated with an increased risk of hand OA only in IL10 G/G or A/A homozygotes (2.54, 1.45-4.47 and 2.60, 1.46-4.62, respectively) but not in heterozygotes (G/A).

Conclusions

Our results suggest that the TNF α gene variants play a role in the etiology of hand OA. In addition, the findings are suggestive of a gene-gene interaction of the TNF α with IL4R and IL10 genes.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2474-15-311) contains supplementary material, which is available to authorized users.

Tumor necrosis factor beta NcoI polymorphism is associated with inflammatory and metabolic markers in multiple sclerosis patients

To evaluate the association between the tumor necrosis factor beta (TNF-β) NcoI polymorphism and inflammatory and metabolic markers in patients with multiple sclerosis (MS) patients and the association of these markers with disease disability, a 782 base-pair fragment of the TNF-β gene was amplified from genomic DNA and digested with the NcoI restriction enzyme. The serum levels of numerous cytokines (IL-1β, IL-12, IL-6, TNF-α, IFN-γ, IL-4, IL-10, and IL-17) serum lipid levels, plasma insulin levels, and the Homeostasis Model Assessment-Insulin Resistance (HOMA-IR) levels were evaluated in 123 female and 43 male patients with MS. Females carrying the TNFB2/B2 genotype presented with decreased IL-4 and IL-10 levels and increased TNF-α, glucose, insulin, and HOMA-IR levels; moreover, there were positive correlations between EDSS and glucose and between EDSS and HOMA-IR in these females. Males carrying the TNFB2/B2 genotype exhibited increased levels of TNF-α, IFN-γ, and IL-17 (p=0.0326) and decreased levels of IL-4, IL-10, insulin, and HOMA-IR; there was a positive correlation between EDSS and TNF-α levels. The TNFB2/B2 genotype of TNF-β NcoI polymorphism was associated with increased inflammatory and metabolic markers and this association was different according to sex of MS patients.

Associations between TNF gene polymorphisms (-308 A/G, -238 A/G, -1031 C/T and -857 T/C) and genetic susceptibility to T1D: a meta-analysis

The aim of this study was to estimate the associations between tumor necrosis factor (TNF) gene polymorphisms and type 1 diabetes (T1D) using meta-analysis. Relevant studies were searched using PubMed and Embase up to August 2013. A total of 32 comparisons from 21 studies examining the associations between TNF polymorphisms and T1D were included in the present meta-analysis. Our meta-analysis identified a significant association between TNF -308 A/G polymorphism A allele and T1D in all subjects [odds ratio (OR) 2.001, 95 % confidence interval (CI) 1.732-2.312). Significant associations of AA and AA+AG genotype of TNF -308 A/G polymorphism with genetic susceptibility to T1D were also found (OR 3.203, 95 % CI 2.373-4.324; OR 2.232, 95 % CI 1.881-2.649). After stratification by ethnicity, significant associations of T1D with TNF -308 A/G polymorphism under all genetic models (A allele and AA, AA+AG genotype) were still detected in European (OR 1.952, 95 % CI 1.675-2.274; OR 3.108, 95 % CI 2.169-4.455; OR 2.249, 95 % CI 1.870-2.706, respectively) and non-European populations (OR 2.152, 95 % CI 1.488-3.112; OR 3.439, 95 % CI 2.000-5.914; OR 2.207, 95 % CI 1.496-3.257, respectively). Our meta-analysis also revealed an association of TNF -857 T/C polymorphism T allele with T1D risk (OR 1.647, 95 % CI 1.431-1.896). Furthermore, analysis of TT and TT+TC genotype indicated the same result patterns as shown by the TNF -857 T/C polymorphism T allele (OR 2.206, 95 % CI 1.467-3.317; OR 1.762, 95 % CI 1.490-2.083). In conclusion, our meta-analysis results indicate that TNF -308 A/G and -857 T/C polymorphisms are involved in the genetic background of T1D.

Interferon-α-induced B-lymphocyte stimulator expression and mobilization in healthy and systemic lupus erthymatosus monocytes

OBJECTIVE

The aim of this study was to investigate the cellular populations and regulatory factors responsible for B-lymphocyte stimulator (BLyS) overexpression in SLE patients.

METHODS

Surface and intracellular BLyS levels were quantified by flow cytometry in healthy and SLE monocytes cultured in the presence of TNF-α, IFN-α, IFN-γ, GM-CSF and SLE immune complexes (SLE-ICs), while soluble BLyS was measured by ELISA. Also, both surface and intracellular BLyS expression by different cell subsets was determined in 23 SLE patients and 16 healthy controls. Disease activity was assessed using classic BILAG index.

RESULTS

In vitro experiments using healthy monocytes showed that IFN-α and SLE-ICs induced a progressive increase in surface-bound BLyS with respect to the intracellular stores. IFN-α-treated SLE monocytes, especially from patients with high anti-dsDNA levels or disease activity, exhibited higher intracellular levels of BLyS that was mobilized to the membrane more rapidly and subsequently released. Furthermore, ex vivo analysis of SLE patients revealed up-regulated BLyS expression in B cells, myeloid and plasmacytoid dendritic cells (DCs), whereas active patients had an increased surface:intracellular BLyS ratio in monocytes and myeloid DCs.

CONCLUSION

Monocyte BLyS induction and mobilization from intra- to extracellular compartments seems to be influenced by IFN-α and disease activity or anti-dsDNA levels. Accordingly, monocytes and myeloid DCs from active patients presented the highest membrane-bound:intracellular BLyS ratio. In addition, expression levels in several blood cells support the existence of generalized immune stimulation in SLE patients.

Association between tumor necrosis factor-α rs1800629 polymorphism and risk of asthma: a meta-analysis

Objective

The purpose of this study was to explore the association between the TNF-α rs1800629 (also refers as -308G/A) polymorphism and asthma susceptibility.

Methods

We searched the Pubmed, Embase, Cochrane Central Register of Controlled Trials (CENTRAL) and Wanfang databases. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to calculate the strength of association.

Results

A total of 34 studies involving 5477 asthma patients and 5962 controls were included in present study. The results indicated that TNF-α rs1800629 polymorphism was significantly associated with asthma risk in a recessive genetic model (OR = 1.46, 95% CI 1.21–1.76, P<0.0001). Subgroup analyses found that the TNF-α rs1800629 polymorphism was significantly associated with asthma risk in West Asians and South Asians (OR = 2.47, 95% CI = 1.48–4.12, P = 0.0005; OR = 1.83, 95% CI = 1.42–2.36, P<0.00001), but not East Asians and Caucasians. Furthermore, significant association also was observed in allergic asthma (OR = 1.51, 95% CI = 1.24–1.83, P<0.0001), adults and children (OR = 1.43, 95 CI% = 1.07–1.91, P = 0.02; OR = 1.57, 95% CI = 1.19–2.06, P = 0.001).

Conclusions

This meta-analysis suggested that the rs1800629 polymorphism in TNF-α was a risk factor for asthma.

Tumor necrosis factor-alpha gene promoter region polymorphism and the risk of coronary heart disease

BACKGROUND

Tumor necrosis factor-alpha (TNF- α ) gene polymorphisms have been implicated in the manifestation of atherosclerosis. Controversy exists regarding the link between the cytokine's variant genotype and CHD among different ethnic groups. There have been fewer studies on the TNF- α gene -1031T>C and -863C>A polymorphisms in relation to CHD. Therefore, the current study was designed to investigate the association of the TNF- α gene -1031T>C and -863C>A polymorphisms with CHD in a Pakistani population.

METHODS

Patients with CHD (n = 310) and healthy individuals (n = 310) were enrolled in this study. Genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

RESULTS

A significant difference was observed in the -863C>A polymorphism between patients with CHD and control subjects (P < 0.0001). CHD risk was positively associated with the variant allele -863A (P < 0.0001) in the study subjects. There was no significant link between the -1031T>C polymorphism and CHD risk in the study population. Haplotypes A-T and A-C of the TNF-alpha gene loci at -863 and -1031 showed higher frequency in the patient group compared with controls (P < 0.05).

CONCLUSION

The TNF- α   -863C>A gene polymorphism was associated with the pathogenesis of CHD while the -1031T>C polymorphism did not show any link with the disease in a Pakistani population.

Genome-wide association study for levels of total serum IgE identifies HLA-C in a Japanese population

Most of the previously reported loci for total immunoglobulin E (IgE) levels are related to Th2 cell-dependent pathways. We undertook a genome-wide association study (GWAS) to identify genetic loci responsible for IgE regulation. A total of 479,940 single nucleotide polymorphisms (SNPs) were tested for association with total serum IgE levels in 1180 Japanese adults. Fine-mapping with SNP imputation demonstrated 6 candidate regions: the PYHIN1/IFI16, MHC classes I and II, LEMD2, GRAMD1B, and chr13∶60576338 regions. Replication of these candidate loci in each region was assessed in 2 independent Japanese cohorts (n = 1110 and 1364, respectively). SNP rs3130941 in the HLA-C region was consistently associated with total IgE levels in 3 independent populations, and the meta-analysis yielded genome-wide significance (P = 1.07×10⁻¹⁰). Using our GWAS results, we also assessed the reproducibility of previously reported gene associations with total IgE levels. Nine of 32 candidate genes identified by a literature search were associated with total IgE levels after correction for multiple testing. Our findings demonstrate that SNPs in the HLA-C region are strongly associated with total serum IgE levels in the Japanese population and that some of the previously reported genetic associations are replicated across ethnic groups.

Association of CTLA4 gene polymorphism (rs5742909) with cervical cancer: a meta-analysis

Previous studies suggested that CTLA4 polymorphism (rs5742909) is associated with susceptibility to cervical cancer. In the present study, we performed a meta-analysis to systematically summarize the possible association between rs5742909 and the risk for cervical cancer. We conducted a search of case–control studies on the associations of rs5742909 with susceptibility to cervical cancer in PubMed, EMBASE, ISI Web of Science, Cochrane Central Register of Controlled Trials, Wanfang database in China, and Chinese National Knowledge Infrastructure databases. We extracted the data from eligible studies for meta-analysis. The association of cervical cancer risk with rs5742909 was estimated by pooled odds ratios (ORs) and 95 % confidence intervals (95 % CIs). There were four studies on rs5742909 and cervical cancer in our meta-analysis. Our results suggested that both T allele frequency (OR = 1.63, 95 % CI 1.06-2.50; P = 0.03) and (TT + CT) genotype distribution (OR = 1.72, 95 % CI 1.07-2.77; P = 0.03) of the rs5742909 were associated with risk for cervical cancer. This meta-analysis suggests that rs5742909 is associated with the risk of cervical cancer. Well-designed studies with larger sample size and more ethnic groups are required to further validate the results.

Genetic variation in the TNFA promoter region and TNFA gene expression in subjects with asthma

OBJECTIVE

Asthma is a chronic disease that affects millions of people. Messenger RNA (mRNA) expression of specific inflammatory markers has been associated with asthma and corticosteroid response. Tumor necrosis factor-α (TNF-α), a pro-inflammatory cytokine, has been shown to have increased expression in airways of asthmatics and may be related to corticosteroid sensitivity. The purpose of this study was to determine how genetic variants within the promoter region of the TNFA gene differ between subjects with asthma and controls. We also investigated how genetic variation affects gene expression.

METHODS

We enrolled 94 subjects between 5 to 54 years of age who met the inclusion and exclusion criteria. TNFA mRNA expression was determined by qRT-PCR on total RNA isolated from the buccal mucosa. Genotyping was performed for TNFA-1031T/C, -857C/T, and -308G/A on genomic DNA isolated from blood with commercially available assays. Gene expression was log-2 transformed and corrected with 2 normalization genes. General linear model, Chi-square test, Fisher's exact test, and Cochran-Mantel-Haenszel test were performed with p < .05.

RESULTS

The TNFA-857C/T polymorphism is associated with asthma in this cohort. The TNFA-857 T allele is underrepresented in pediatric subjects with asthma relative to those without asthma (3% and 29% of individuals, respectively, p = .01). Furthermore, a TNFA haplotype combination containing -1031T/-857C/-308G and -1031T/-857T/-308G is associated with lower expression of TNF-α mRNA (p = .01) in pediatric subjects.

CONCLUSIONS

Presence of the TNFA-857T allele may be protective in the development of asthma and a haplotype combination that contains the TNFA-857T allele is associated with TNFA expression.

The +252A/G polymorphism in the lymphotoxin-α gene increases the risk of asthma: a meta-analysis

BACKGROUND AND OBJECTIVE

A number of studies have shown that the +252A/G polymorphism (rs909253) in the lymphotoxin-α (LT-α) gene is implicated in susceptibility to asthma. However, the findings have been inconclusive. The aim of this study was to investigate the association between the +252A/G polymorphism in the LT-α gene and the risk of asthma by performing a meta-analysis.

METHODS

The Pubmed and Embase databases were searched for all studies relating to this polymorphism and the risk of asthma. Statistical analyses were performed using the Revman4.2 and STATA 10.0 software.

RESULTS

Thirteen case-control studies that included a total of 2220 cases and 6428 controls were included in the meta-analysis. There was no significant association between this polymorphism and the risk of asthma in the all-combined analysis (odds ratio (OR) 1.14, 95% confidence interval (CI): 0.89-1.45 for GG+GA vs AA). In a subgroup analysis by ethnicity, no significant association with asthma risk was identified in Asians (OR 1.31, 95% CI: 0.97-1.77) or Europeans (OR 1.08, 95% CI: 0.77-1.53). In a subgroup analysis by age, a significantly increased risk was identified among adults (OR 1.25, 95% CI: 1.03-1.50) but not children (OR 1.04, 95% CI: 0.28-3.89). In a subgroup analysis by atopic status, a significantly elevated risk was identified among atopic (OR 1.55, 95% CI: 1.28-1.87) but not non-atopic individuals (OR 0.94, 95% CI: 0.53-1.68).

CONCLUSIONS

This meta-analysis suggested that the +252A/G polymorphism in the LT-α gene is a risk factor for asthma in adults and atopic populations.

Airway inflammation and hypothalamic-pituitary-adrenal axis activity in asthmatic adults with depression

OBJECTIVE

To investigate the features of airway inflammation and hypothalamic-pituitary-adrenal axis (HPAA) activity in patients with asthma accompanied by depression.

METHODS

Adult asthmatics were recruited and enrolled into one of the two groups based on scores on the Hamilton Depression Rating Scale (HAMD): asthmatics with depression (HAMD score ≥8, n = 23), and asthmatics without depression (HAMD score <8, n = 41). In addition, 27 healthy individuals and 21 adults with depression only were enrolled as controls. Induced sputum and blood samples were collected for measurement of cytokines and other inflammatory factors. The diurnal rhythm profiles of salivary cortisol and other hormones were obtained for assessment of the HPAA activity.

RESULTS

For the group of asthmatics with depression, the mean HAMD score was 19.0, and for the group of asthmatics without depression, the HAMD score averaged 4.9(p < .001). Serum and sputum tumor necrosis factor alpha (TNF-α) were significantly higher in asthmatics with depression than those in the other groups (p < .05) while serum interferon-gamma (IFN-γ) was lower in asthmatics with depression than that in the other groups (p < .05). Twenty-four-hour urinary cortisol, salivary cortisol at 8 a.m. and 4 p.m. were lower in asthmatics with depression compared to other groups (p < .05).

CONCLUSIONS

As compared to healthy individuals and those with asthma or depression alone, individuals with comorbid depression and asthma showed the highest level of pro-inflammatory cytokines and the lowest level of anti-inflammatory cytokines and cortisol. These observations may serve as a valuable reference for diagnosis and clinic therapies of depression in asthmatics.

Impact of single nucleotide polymorphism in tumor necrosis factor-α gene 308G/A in Egyptian asthmatic children and wheezing infants

Bronchial asthma is a common disease with multiple determinants that include genetic variation. Although tumor necrosis factor alpha (TNF-α) is a major pro-inflammatory cytokine, the functions of genetic polymorphisms in this cytokine has not been thoroughly examined in the context of asthma pathology. Therefore, we aimed to investigate whether single nucleotide polymorphism (SNP) in TNF-α is associated with asthma and wheezing and whether the association is related to the severity of the disease and other epidemiological factors. Frequencies of TNF-α-308G/A polymorphism were compared in 100 asthmatic children, 100 wheezy infants and 100 age and gender matched controls. Genotype frequencies for TNF-α-308G/A were significantly higher in asthmatic children (60%) and wheezy infants (68%) than the control group (30%). Higher serum levels of TNF-α were observed in genotypes G/A and G/G of asthmatic children and wheezy infants than in controls. No association was found between the G/A polymorphism and the severity of the disease, the total eosinophil count and IgE levels in both groups. We can conclude that genetic variation in TNF-α-308G/A may contribute to childhood asthma and wheezing. These findings could be helpful for future early intervention studies which may have a potential impact on family counseling and management.

Polymorphism of tumor necrosis factor alpha (TNF-alpha) gene promoter, circulating TNF-alpha level, and cardiovascular risk factor for ischemic stroke

Background

Tumor necrosis factor-α (TNF-α) is one of the most typical pro-inflammatory cytokines with both beneficial and destructive properties for the central nervous system. Increasing evidences have demonstrated the important role of TNF-α in the development of ischemic stroke, but studies examining the possible association with stroke or direct functional effects of polymorphisms in TNF-α have been contradictory.

Findings

In this study, a 2-kb length of the proximal promoter of the TNF-α was screened and four polymorphisms were investigated in the case–control study. Our data confirmed the association between -308G/A variant with stroke in 1,388 stroke patients and 1,027 controls and replicated in an independent population of 961 stroke patients and 821 controls (odds ratio (OR) = 1.34, 95% confidence interval (CI) =1.02 to 1.77 and OR = 1.56, 95% CI = 1.09 to 2.23, respectively). To reconcile the association between polymorphisms and stroke and to give a comprehensive picture of the genetic architecture of this important gene, we performed a meta-analysis of 15 published studies in an Asian population. Our results demonstrated an association between rs1800629 and ischemic stroke (OR = 1.43, 95% CI = 1.21 to 1.69). Another meta-analysis results of 14 studies demonstrated that ischemic stroke patients have higher serum TNF-α level than the control subjects (standardized mean difference (SMD) = 2.33, 95% CI = 1.85 to 2.81). In vitro evaluation of potential interaction between variants of the TNF-α gene (−308G/A, -857C/T, and -1031T/C) demonstrated that these three polymorphisms could interact together to determine the overall activity of the TNF-α gene.

Conclusions

These findings strongly implicate the involvement of TNF-α in the pathogenesis of stroke.

TNF-alpha gene (TNFA) variants increase risk for multi-organ dysfunction syndrome (MODS) in acute pancreatitis

BACKGROUND/OBJECTIVES

Acute pancreatitis (AP) is a complex inflammatory syndrome with unpredictable progression to systemic inflammation and multi-organ dysfunction syndrome (MODS). Tumor necrosis factor alpha (TNF-α) is a cytokine that may link inflammation to the systemic inflammatory response syndrome (SIRS), which usually precedes MODS. Small genetic cohort studies of the TNFA promoter in AP produced ambiguous results. We performed a comprehensive evaluation of TNFA promoter variants to assess both susceptibility to AP and risk of progression to MODS.

METHODS

We prospectively ascertained 401 controls and 211 patients with AP that were assessed for persistent SIRS (>48 h) and MODS. MODS was defined as failure of ≥2 organ systems (cardiovascular, pulmonary, and/or renal) persisting more than 48 h. Subjects were genotyped by DNA sequencing and analyzed for SNPs at -1031 C/T (rs1799964), -863 A/C (rs1800630), -857 C/T (rs1799724), -308 A/G (rs1800629), and -238 A/G (rs361525).

RESULTS

Twenty-three of 211 AP patients (11%) developed MODS. TNFA promoter variants were not associated with susceptibility to AP, but progression to MODS was associated with the minor allele at -1031C (56.5% vs. 32.4% P = 0.022, OR: 2.7; 95%CI: 1.12-6.51) and -863A (43.5% vs. 21.8% P = 0.022, OR: 2.76; 95%CI: 1.12-6.74).

CONCLUSION

TNFA promoter variants do not alter susceptibility to AP, but rather the TNF-α expression-enhancing -1031C and -863A alleles significantly increased the risk of AP progression to MODS. These data, within the context of previous studies, clarify the risk of specific genetic variants in TNFA and therefore the role of TNF-α in the overall AP syndrome.

Tumour necrosis factor gene polymorphism and disease prevalence

Tumour necrosis factor (TNF), an important proinflammatory cytokine, plays a role in the regulation of cell differentiation, proliferation and death, as well as in inflammation, innate and adaptive immune responses, and also implicated in a wide variety of human diseases. The presence of DNA sequence variations in regulatory region might interfere with transcription of TNF gene, influencing the circulating level of TNF and thus increases the susceptibility to human diseases (infectious, cancer, autoimmune, neurodegenerative and other diseases). In this review, we have comprehensively analysed various published case-control studies of different types of human diseases, in which TNF gene polymorphism played a role, and computationally predicted several single nucleotide polymorphisms (SNPs) lie in transcription factor-binding sites (TFBS) of transcription factors (TFs). It has been observed that TNF enhancer polymorphism is implicated in several diseases, and TNF rs1800629 and rs361525 SNPs are the most important in human disease susceptibility as these might influence the transcription of TNF gene. Thirty-two SNPs lies in TFBS of 20 TFs have been detected in the TNF upstream region. It has been found that TNF enhancer polymorphism influences the serum level of TNF in different human diseases and thus affects the susceptibility to diseases. The presence of DNA sequence variation in TNF gene causes the modification of transcriptional regulation and thus responsible for association of susceptibility/resistance with human diseases.

Identification of possible genetic polymorphisms involved in cancer cachexia: a systematic review

Cancer cachexia is a polygenic and complex syndrome. Genetic variations in regulation of the inflammatory response, muscle and fat metabolic pathways, and pathways in appetite regulation are likely to contribute to the susceptibility or resistance to developing cancer cachexia. A systematic search of Medline and EmBase databases, covering 1986-2008 was performed for potential candidate genes/genetic polymorphisms relating to cancer cachexia. Related genes were then identified using pathway functional analysis software. All candidate genes were reviewed for functional polymorphisms or clinically significant polymorphisms associated with cachexia using the OMIM and GeneRIF databases. Genes with variants which had functional or clinical associations with cachexia and replicated in at least one study were entered into pathway analysis software to reveal possible network associations between genes. A total of 184 polymorphisms with functional or clinical relevance to cancer cachexia were identified in 92 candidate genes. Of these, 42 polymorphisms (in 33 genes) were replicated in more than one study with 13 polymorphisms found to influence two or more hallmarks of cachexia (i.e. inflammation, loss of fat mass and/or lean mass and reduced survival). Thirty-three genes were found to be significantly interconnected in two major networks with four genes (ADIPOQ, IL6, NFKB1 and TLR4) interlinking both networks. Selection of candidate genes and polymorphisms is a key element of multigene study design. The present study provides an initial framework to select genes/polymorphisms for further study in cancer cachexia, and to develop their potential as susceptibility biomarkers of developing cachexia.

The -308 G/A polymorphism in TNF-α gene is associated with asthma risk: an update by meta-analysis

BACKGROUND

The -308 G/A polymorphism in TNF-α gene has been extensively investigated for association to asthma; however, results of different studies have been inconsistent. The aim of this study is to comprehensively evaluate the genetic risk of -308 G/A polymorphism in TNF-α gene for asthma.

METHODS

A meta-analysis was carried out to analyze the association between the -308 G/A polymorphism TNF-α gene and asthma risk.

RESULTS

A total of 4717 cases and 5012 controls in 29 case-control studies were included in this meta-analysis. The result indicated that the variant A allele carriers had a 38% increased risk of asthma, when compared with the homozygote GG (odds ratio (OR) = 1.40, 95% confidence interval (CI), 1.13-1.68 for AA + AG vs. GG). In the subgroup analysis by ethnicity, significant elevated risks were associated with A allele carriers in Asians (OR = 1.53, 95% CI = 1.17-2.01 and P = 0.002) but not in Caucasians(OR = 1.06, 95% CI = 0.75-1.50 and P = 0.73). In the subgroup analysis by age, significant elevated risks were associated with A allele carriers in adults (OR = 1.44, 95% CI = 1.14-1.81, and P = 0.002) and children (OR = 1.37, 95% CI = 1.03-1.82, and P = 0.003). In the subgroup analysis by atopic status, significant elevated risks of asthma were associated with A allele carriers in atopic population (OR = 1.68, 95% CI = 1.34-2.10, and P < 0.00001) but not in non-atopic population (OR = 0.98, 95% CI = 0.58-1.68, and P = 0.95).

CONCLUSIONS

Our results suggest that the TNF-α -308 G/A polymorphism contributes to susceptibility to asthma.

Tumour necrosis factor-α promoter region polymorphisms affect the course of spontaneous HBsAg clearance

BACKGROUND

This study aimed to investigate the roles of tumour necrosis factor-α (TNF-α) gene polymorphisms in the spontaneous clearance of HBsAg after a hepatitis B virus (HBV) infection.

METHODS

Polymorphisms in the TNF-α (-1031 T to C, -863 C to A, -857 C to T, -308 G to A and -238 G to A transition) gene were evaluated in 274 chronic HBV-infected patients and 194 patients with resolved HBV infection. The peripheral blood mononuclear cells (PBMC) isolated from 77 (28%) of the 274 chronic HBV-infected patients with negative HBeAg and positive antibody to HBeAg were stimulated with HBcAg. Data on TNF-α genotypes and phenotypes in subjects with/without the A allele at the TNF-α-863 promoter single nucleotide polymorphism (rs1800630) were compared.

RESULTS

The A allele in the -863 promoter region of the TNF-α gene was present in 154 (56.2%) chronic HBV-infected patients and 87 (44.8%) patients who recovered from HBV infection (odds ratio 1.58; P<0.01). The TNF-α-863 A allele genotype predicted lower TNF-α production by PBMC after in vitro HBcAg stimulation (P<0.02).

CONCLUSIONS

The A allele at the -863 locus of the promoter region of the TNF-α gene predicts lower HBcAg-inducible TNF-α secretion. It is also associated with chronicity of HBV infection.

Identification of the Mhc region as an asthma susceptibility locus in recombinant congenic mice

Mouse models of allergic asthma are characterized by airway hyperreactivity (AHR), Th2-driven eosinophilic airway inflammation, high allergen-specific IgE (anti-OVA IgE) levels in serum, and airway remodeling. Because asthma susceptibility has a strong genetic component, we aimed to identify new asthma susceptibility genes in the mouse by analyzing the asthma phenotypes of the Leishmania major resistant (lmr) recombinant congenic (RC) strains. The lmr RC strains are derived from C57BL/6 and BALB/c intercrosses and carry congenic loci on chromosome 17 (lmr1) and 9 (lmr2) in both backgrounds. Whereas the lmr2 locus on chromosome 9 contributes to a small background-specific effect on anti-OVA IgE and AHR, the lmr1 locus on chromosome 17 mediates a strong effect on Th2-driven eosinophilic airway inflammation and background-specific effects on anti-OVA IgE and AHR. The lmr1 locus contains almost 600 polymorphic genes. To narrow down this number of candidate genes, we performed genome-wide transcriptional profiling on lung tissue from C.lmr1 RC mice and BALB/c control mice. We identified a small number of differentially expressed genes located within the congenic fragment, including a number of Mhc genes, polymorphic between BALB/c and C57Bl/6. The analysis of asthma phenotypes in the C.B10-H2b RC strain, carrying the C57Bl/6 haplotype of the Mhc locus in a BALB/c genetic background, reveals a strikingly similar asthma phenotype compared with C.lmr1, indicating that the differentially expressed genes located within the C.B10-H2b congenic fragment are the most likely candidate genes to contribute to the reduced asthma phenotypes associated with the C57Bl/6 allele of lmr1.

ctla-4 gene variations may influence cervical cancer susceptibility

BACKGROUND

CTLA-4 is the key player of the immune tolerance. Particular genotypes of ctla-4 have been reported to be associated with various diseases.

OBJECTIVE

We aimed to evaluate the role of four single nucleotide polymorphisms (SNPs) of ctla-4 gene in cervical cancer.

METHODS

55 patients and 110 healthy controls were genotyped for four polymorphic loci, three in promoter region; -1722(T/C), -1661(A/G), -318(C/T) and one in exon 1; +49(A/G) using PCR-ARMS and -RFLP methods.

RESULTS

At position -1661 the frequency of A/A homozygote and A allele were lower in patients than in controls. (P=0.01, P=0.035; respectively), while at position -318 the frequency of C/C homozygote and C allele were increased in patients (P=0.021, P=0.025; respectively). These significances, however, do not stand the Bonferroni correction suggesting that the effect of multiple comparisons should not be ignored. The haplotype analysis demonstrated 9 haplotypes, of which, 5 were observed in both groups with no significant different frequencies. The TGTA haplotype, however, was only observed in control group (9.54%, p=0.002) and the TGCG haplotype was only occurred in cervical cancer patients (6.48%, p=0.0003). The differences were still significant after Bonferroni correction.

CONCLUSION

As a conclusion TGTA haplotype as well as A allele at position -1661 might imply a protective role whereas TGCG haplotype as well as C allele at locus -318 might render susceptibility to cervical cancer. Investigation of ctla-4 gene variants in other ethnic populations will consolidate the findings of this study.

IL-10 and TNFalpha genotypes in SLE

The production of two regulators of the inflammatory response, interleukin 10 (IL-10) and tumor necrosis factor α (TNFα), has been found to be deeply deregulated in SLE patients, suggesting that these cytokines may be involved in the pathogenesis of the disease. Genetic polymorphisms at the promoter regions of IL-10 and TNFα genes have been associated with different constitutive and induced cytokine production. Given that individual steady-state levels of these molecules may deviate an initial immune response towards different forms of lymphocyte activation, functional genetic variants in their promoters could influence the development of SLE. The present review summarizes the information previously reported about the involvement of IL-10 and TNFα genetic variants on SLE appearance, clinical phenotype, and outcome. We show that, in spite of the heterogeneity of the populations studied, the existing knowledge points towards a relevant role of IL-10 and TNFα genotypes in SLE.