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Kaur S, Arpna, Jha D, Khosla R, Kaur M, Parkash J, Sharma A, Changotra H. Autophagy related gene 5 polymorphism rs17587319 (C/G) in asthmatic patients in North Indian population. J Asthma 2024; 61:472-478. [PMID: 38009708 DOI: 10.1080/02770903.2023.2289156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 11/25/2023] [Indexed: 11/29/2023]
Abstract
Objective: Genetic background and environmental stimuli play an important role in asthma, which is an individual's hyper-responsiveness to these stimuli leading to airway inflammation. Autophagy Related Gene 5 (ATG5) plays a critical role in the autophagy pathway and has been shown to be involved in asthma. The genetic polymorphisms in the ATG5 have been reported to predispose individuals to asthma. The role of single nucleotide polymorphism rs17587319 (C/G) of ATG5 in asthma has not been studied so far. Materials and methods: In this study, we in silico analysed rs17587319 (C/G) using web-based tools Human Splice Finder (HSF) and RegulomeDB and further a case-control study was conducted that included 187 blood samples (94 asthmatic and 93 healthy controls). Results: In silico analysis suggested alteration of splicing signals by this intronic variant. The samples were genotyped by applying the PCR-RFLP method. The MAF obtained was 0.022 and 0.043 in healthy controls and asthmatic individuals, respectively. The statistical analysis revealed no association (allelic model, OR = 2.02, 95%CI = 0.59-6.83, p = 0.25; co-dominant model, OR = 2.06, 95%CI = 0.6-7.12, p = 0.24) of rs17587319 (C/G) with the susceptibility to asthma in the north Indian population. Conclusions: In conclusion, rs17587319 (C/G) of ATG5 does not predispose individuals to asthma in our part of the world. Further studies are needed including more number of samples to ascertain the role of this polymorphism in asthma.
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Affiliation(s)
- Sargeet Kaur
- Department of Biotechnology and Bioinformatics, Jaypee University of Information Technology, Solan, Himachal Pradesh, India
| | - Arpna
- Department of Molecular Biology and Biochemistry, Guru Nanak Dev University, Amritsar, Punjab, India
| | - Durga Jha
- Department of Biotechnology and Bioinformatics, Jaypee University of Information Technology, Solan, Himachal Pradesh, India
| | - Rajiv Khosla
- Department of Biotechnology, Doaba College Jalandhar, Punjab, India
| | - Manpreet Kaur
- Department of Human Genetics, Guru Nanak Dev University, Amritsar, Punjab, India
| | - Jyoti Parkash
- Centre for Animal Sciences, School of Basic and Applied Sciences, Central University of Punjab, Bathinda, India
| | - Arti Sharma
- Department of Computational Biology, School of Biological Sciences, Central University of Punjab, Bathinda, Punjab, India
| | - Harish Changotra
- Department of Molecular Biology and Biochemistry, Guru Nanak Dev University, Amritsar, Punjab, India
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Zhang Y, Wang HC, Feng C, Yan M. Analysis of the Association of Polymorphisms rs5743708 in TLR2 and rs4986790 in TLR4 with Atopic Dermatitis Risk. Immunol Invest 2018; 48:169-180. [PMID: 30273064 DOI: 10.1080/08820139.2018.1508228] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
BACKGROUND We carried out a meta-analysis to assess whether Toll-like receptor 2 (TLR2) rs5743708 and Toll-like receptor 4 (TLR4) rs4986790 polymorphisms are associated with the risk of atopic dermatitis. METHODS A systematic search of PubMed, Embase, and Web of Science was performed to identify eligible case-control studies on the association of rs5743708 and rs4986790 with the risk of atopic dermatitis. Statistical analyses of the odds ratio (OR), 95% confidence interval (CI), and p value were performed using STATA software. RESULTS Our meta-analysis included a total of nine case-control studies, all involving Caucasian populations. With respect to the TLR2 rs5743708 G/A polymorphism, there was a statistically significant difference in the overall risk of atopic dermatitis between the case and control groups [OR = 2.07, p value of association test, p(association) = 0.001 in allele (A vs. G) model; OR = 1.93, p(association) = 0.004 in carrier (A vs. G) model; OR = 2.07, p(association) = 0.001 in heterozygote (GA vs. GG) model; OR = 1.99, p(association) = 0.001 in dominant (GA+ AA vs. GG) model]. Similar positive results were observed in the subgroup analysis of "population-based control." For the TLR4 rs4986790 A/G polymorphism, an increased atopic dermatitis risk was detected in the case group under the allele [OR = 1.78, p(association) = 0.013], carrier [OR = 1.69, p(association) = 0.027] and heterozygote [OR = 1.74, p(association) = 0.020] models, but not the dominant [OR = 1.44, p(association) = 0.070] model, in comparison to the population-based control group. CONCLUSION Our meta-analysis revealed a novel finding that the heterogeneous "GA" genotype of the TLR2 rs5743708 and "AG" genotype of the TLR4 rs4986790 may be associated with increased susceptibility to atopic dermatitis in Caucasians.
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Affiliation(s)
- Yuan Zhang
- a Department of Dermatology , Shengli Oilfield Central Hospital , Shandong , China
| | - Hui-Cong Wang
- a Department of Dermatology , Shengli Oilfield Central Hospital , Shandong , China
| | - Chao Feng
- a Department of Dermatology , Shengli Oilfield Central Hospital , Shandong , China
| | - Min Yan
- a Department of Dermatology , Shengli Oilfield Central Hospital , Shandong , China
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Ávila-Castellano R, García-Lozano JR, Cimbollek S, Lucendo AJ, Bozada JM, Quiralte J. Genetic variations in the TLR3 locus are associated with eosinophilic esophagitis. United European Gastroenterol J 2017; 6:349-357. [PMID: 29774148 DOI: 10.1177/2050640617732643] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Accepted: 08/23/2017] [Indexed: 12/26/2022] Open
Abstract
Background Eosinophilic esophagitis (EoE) is an antigen-driven disease mediated by an abnormal immune Th2 response. Objective The objective of this article is to investigate genes associated with regulating immune responses leading to disease susceptibility. Methods Twenty-seven tag single nucleotide polymorphisms (tSNPs) selected in five candidate genes (TLR3, TLR4, FOXP3, FLG and TSLP) were genotyped in 218 EoE patients and 376 controls. Skin prick tests were carried out in EoE patients with a panel of 17 aeroallergens and 22 plant- and animal-derived foods. Results Five tSNPs located in the TSLP locus and one tSNP located in the TLR3 locus were significantly associated with EoE. The interactions between TLR3 and TSLP loci were analyzed. TLR3+/TSLP- and TLR3-/TSLP+ individuals showed a significantly reduced susceptibility to EoE compared to TLR3-/TSLP- individuals (OR = 0.66, p = 0.036 and OR = 0.23, p = 0.00014, respectively). Likewise, TLR3+/TSLP+ individuals showed the most decreased susceptibility of developing EoE (OR = 0.16, p = 0.0001). However, the interaction gain attributed to the combination of both genes was negative (IG = -4.52%), which indicated redundancy or independent effect. Additionally, TLR3 locus was found to be associated with aeroallergen and food sensitization in EoE patients (OR = 9.67, pc = 0.025 and OR = 0.53, pc = 0.048, respectively). Conclusion TLR3 constitutes a novel genetic susceptibility locus for developing EoE, and the effects would be independent of TSLP.
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Affiliation(s)
| | - José-Raúl García-Lozano
- Servicio de Inmunología, Unidad de Gestión Clínica "Laboratorios Clinicos," Instituto de Biomedicina de Sevilla (IBiS), Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, Sevilla, Spain
| | - Stefan Cimbollek
- 1Division of Allergy, UGC Intercentros, Hospital Universitario Virgen del Rocío, Sevilla, Spain
| | - Alfredo J Lucendo
- Department of Gastroenterology, Hospital General de Tomelloso, Tomelloso, Spain.,Centro de Investigación Biomédica En Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Madrid, Spain
| | - Juan-Manuel Bozada
- 5Division of Gastroenterology, Hospital Universitario Virgen del Rocío, Sevilla, Spain
| | - Joaquín Quiralte
- 1Division of Allergy, UGC Intercentros, Hospital Universitario Virgen del Rocío, Sevilla, Spain
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4
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Gao Y, Xiao H, Wang Y, Xu F. Association of single-nucleotide polymorphisms in toll-like receptor 2 gene with asthma susceptibility: A meta-analysis. Medicine (Baltimore) 2017; 96:e6822. [PMID: 28514297 PMCID: PMC5440134 DOI: 10.1097/md.0000000000006822] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND An increasing number of studies have been carried out on the relationship between polymorphisms in toll-like receptor 2 (TLR2) gene and asthma risk. However, the results were controversial. With the purpose of yielding a more reliable estimation of the association, we conducted the present meta-analysis. METHODS Multiple electronic databases up to August 22, 2016 were searched for literature retrieval. The association between the asthma susceptibility and the rs5743708 polymorphism, rs3804099 polymorphism, rs3804100 polymorphism, and rs4696480 polymorphism in TLR2 gene was appraised. The odds ratios (ORs) with 95% confidence intervals (CIs) under different genetic models were calculated. RESULTS A total of 13 studies were eligible in our meta-analysis according to the predefined inclusion and exclusion criteria. There was no significant association between asthma risk and rs5743708, rs3804099, and rs3804100 polymorphisms in TLR2 gene under any genetic model. With respect to the TLR2 rs4696480 polymorphism, significant association was detected between asthma susceptibility and TLR2 rs4696480 polymorphism under dominant model (OR = 2.455, 95% CI = 1.235-4.88, P = .01) and codominant 3 model (OR = 2.776, 95% CI = 1.199-6.427, = 0.017). CONCLUSIONS Our meta-analysis reveals that the TLR2 rs4696480 polymorphism is significantly associated with asthma susceptibility, and the TLR2 rs4696480 polymorphism is a risk factor for asthma.
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Affiliation(s)
| | - Hanyan Xiao
- Department of Neurology, Second Affiliated Hospital of Mudanjiang Medical College, Mudanjiang, Heilongjiang Province, China
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5
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Lau MYZ, Dharmage SC, Burgess JA, Win AK, Lowe AJ, Lodge C, Perret J, Hui J, Thomas PS, Morrison S, Giles GG, Hopper J, Abramson MJ, Walters EH, Matheson MC. The interaction between farming/rural environment and TLR2, TLR4, TLR6 and CD14 genetic polymorphisms in relation to early- and late-onset asthma. Sci Rep 2017; 7:43681. [PMID: 28262750 PMCID: PMC5337969 DOI: 10.1038/srep43681] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Accepted: 01/24/2017] [Indexed: 12/22/2022] Open
Abstract
Asthma phenotypes based on age-of-onset may be differently influenced by the interaction between variation in toll-like receptor (TLR)/CD14 genes and environmental microbes. We examined the associations between single-nucleotide polymorphisms (SNP) in the TLR/CD14 genes and asthma, and their interaction with proxies of microbial exposure (childhood farm exposure and childhood rural environment). Ten SNPs in four genes (TLR2, TLR4, TLR6, CD14) were genotyped for 1,116 participants from the Tasmanian Longitudinal Health Study (TAHS). Using prospectively collected information, asthma was classified as never, early- (before 13 years) or late-onset (after 13 years). Information on childhood farm exposure/childhood rural environment was collected at baseline. Those with early-onset asthma were more likely to be males, had a family history of allergy and a personal history of childhood atopy. We found significant interaction between TLR6 SNPs and childhood farm exposure. For those with childhood farm exposure, carriers of the TLR6-rs1039559 T-allele (p-interaction = 0.009) and TLR6-rs5743810 C-allele (p-interaction = 0.02) were associated with lower risk of early-onset asthma. We suggest the findings to be interpreted as hypothesis-generating as the interaction effect did not withstand correction for multiple testing. In this large, population-based longitudinal study, we found that the risk of early- and late-onset asthma is differently influenced by the interaction between childhood farming exposure and genetic variations.
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Affiliation(s)
- Melisa Y Z Lau
- Allergy and Lung Health Unit, Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, the University of Melbourne, Victoria, Australia
| | - Shyamali C Dharmage
- Allergy and Lung Health Unit, Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, the University of Melbourne, Victoria, Australia.,Murdoch Childrens Research Institute, Melbourne, Victoria, Australia
| | - John A Burgess
- Allergy and Lung Health Unit, Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, the University of Melbourne, Victoria, Australia
| | - Aung K Win
- Allergy and Lung Health Unit, Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, the University of Melbourne, Victoria, Australia
| | - Adrian J Lowe
- Allergy and Lung Health Unit, Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, the University of Melbourne, Victoria, Australia.,Murdoch Childrens Research Institute, Melbourne, Victoria, Australia
| | - Caroline Lodge
- Allergy and Lung Health Unit, Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, the University of Melbourne, Victoria, Australia.,Murdoch Childrens Research Institute, Melbourne, Victoria, Australia
| | - Jennifer Perret
- Allergy and Lung Health Unit, Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, the University of Melbourne, Victoria, Australia
| | - Jennie Hui
- School of Population Health, the University of Western Australia, Perth, Australia
| | - Paul S Thomas
- Inflammation and Infection Research Centre, University of New South Wales, Australia
| | - Stephen Morrison
- Department of Medicine, the University of Queensland, Queensland, Australia
| | - Graham G Giles
- Cancer Epidemiology Centre, Cancer Council Victoria, Victoria, Australia.,School of Public Health &Preventive Medicine, Monash University, Melbourne, Victoria, Australia
| | - John Hopper
- Allergy and Lung Health Unit, Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, the University of Melbourne, Victoria, Australia
| | - Michael J Abramson
- School of Public Health &Preventive Medicine, Monash University, Melbourne, Victoria, Australia
| | - E Haydn Walters
- Allergy and Lung Health Unit, Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, the University of Melbourne, Victoria, Australia.,School of Medicine, University of Tasmania, Tasmania, Australia
| | - Melanie C Matheson
- Allergy and Lung Health Unit, Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, the University of Melbourne, Victoria, Australia.,Murdoch Childrens Research Institute, Melbourne, Victoria, Australia
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6
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Papaioannou AI, Spathis A, Kostikas K, Karakitsos P, Papiris S, Rossios C. The role of endosomal toll-like receptors in asthma. Eur J Pharmacol 2016; 808:14-20. [PMID: 27677226 DOI: 10.1016/j.ejphar.2016.09.033] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Revised: 04/06/2016] [Accepted: 09/23/2016] [Indexed: 01/04/2023]
Abstract
Asthma is a heterogeneous inflammatory disease caused by association of genetic and environmental factors and its incidence has significantly increased over the latest years. The clinical manifestations of asthma are the result of airway hyper-reactivity to a variety of triggers such as aeroallergens, viral and bacterial components. Toll-like receptors (TLRs) are pathogen associated molecular pattern receptors, which are also expressed in the lung tissue as well as in several cells of the innate and adaptive immune system. Ligation of TLRs results in alterations in the expression of several inflammatory and anti-inflammatory mediators, which are known to be involved in the pathogenesis of asthma. The endosomal TLRs have been shown to be associated with the induction of asthmatic inflammation (TLR3), and with disease exacerbations (TLR7, TLR8 and TLR9). Targeting these receptors seems to be an effective choice for suppressing airway inflammation, eosinophilia and airway hyperresponsiveness in asthmatic patients. In this review we provide information regarding endosomal TLRs and their role in the pathogenesis of asthma as well as their potential use as targets for the development of novel treatments for the therapy of asthma.
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Affiliation(s)
- Andriana I Papaioannou
- 2nd Respiratory Medicine Department, "Attikon" University Hospital, Athens Medical School, National and Kapodistrian University of Athens, Greece.
| | - Aris Spathis
- Department of Cytopathology, "Attikon" University Hospital, Athens Medical School, National and Kapodistrian University of Athens, Greece
| | - Konstantinos Kostikas
- 2nd Respiratory Medicine Department, "Attikon" University Hospital, Athens Medical School, National and Kapodistrian University of Athens, Greece
| | - Petros Karakitsos
- Department of Cytopathology, "Attikon" University Hospital, Athens Medical School, National and Kapodistrian University of Athens, Greece
| | - Spyros Papiris
- 2nd Respiratory Medicine Department, "Attikon" University Hospital, Athens Medical School, National and Kapodistrian University of Athens, Greece
| | - Christos Rossios
- Airway Disease Section, National Heart and Lung Institute, Imperial College London, UK
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7
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Linking Endotoxins, African Dust PM10 and Asthma in an Urban and Rural Environment of Puerto Rico. Mediators Inflamm 2015; 2015:784212. [PMID: 26681839 PMCID: PMC4670654 DOI: 10.1155/2015/784212] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 10/22/2015] [Accepted: 10/25/2015] [Indexed: 11/21/2022] Open
Abstract
African Dust Events (ADE) are a seasonal phenomenon that has been suggested to exacerbate respiratory and proinflammatory diseases in Puerto Rico (PR). Increases in PM10 concentration and the effects of biological endotoxins (ENX) are critical factors to consider during these storms. ENX promote proinflammatory responses in lungs of susceptible individuals through activation of the Toll-like receptors (TLR2/4) signaling pathways. The objective of the study was to evaluate the toxicological and proinflammatory responses stimulated by ADE PM10 ENX reaching PR using human bronchial epithelial cells. PM10 organic extracts from a rural and urban site in PR (March 2004) were obtained from ADE and non-ADE and compared. A retrospective data analysis (PM10 concentration, aerosol images, and pediatric asthma claims) was performed from 2000 to 2012 with particular emphasis in 2004 to classify PM samples. Urban extracts were highly toxic, proinflammatory (IL-6/IL-8 secretion), and induced higher TLR4 expression and NF-κB activation compared to rural extracts. ENX were found to contribute to cytotoxicity and inflammatory responses provoked by urban ADE PM10 exposure suggesting a synergistic potency of local and natural ENX incoming from ADE. The contribution of ADE PM10 ENX is valuable in order to understand interactions and action mechanisms of airborne pollutants as asthma triggers in PR.
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8
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Tizaoui K, Kaabachi W, Hamzaoui K, Hamzaoui A. Association of Single Nucleotide Polymorphisms in Toll-like Receptor Genes With Asthma Risk: A Systematic Review and Meta-analysis. ALLERGY, ASTHMA & IMMUNOLOGY RESEARCH 2014; 7:130-40. [PMID: 25729620 PMCID: PMC4341334 DOI: 10.4168/aair.2015.7.2.130] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Revised: 04/13/2014] [Accepted: 05/02/2014] [Indexed: 12/26/2022]
Abstract
Purpose Asthma is a complex disease, with contributions from multiple genes, various genetic backgrounds, and environmental factors. Many human epidemiological studies have demonstrated that single nucleotide polymorphisms (SNPs) in Toll-like receptor (TLR) genes are inconsistently associated with asthma risk. Some have demonstrated differences concerning the study design and effect size, and conflicting results have been reported. A meta-analysis is necessary to determine the magnitude of this association. Methods Following the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines, a systematic search and meta-analysis of the literature was conducted to estimate the association of SNPs in TLR genes with asthma risk. We screened the medical literature based on the following keyword searches in MEDLINE and EMBASE databases: 'TLR', 'polymorphism', 'asthma', and their combinations. Results Meta-analysis of eight studies on TLR4 Asp299Gly showed a marginal association of TLR4 with asthma risk (odds ratio [OR]=0.814 [95% confidence interval [CI], 0.652-1.016; P=0.069]) in the recessive model. TLR4 Thr399Ile was not associated with asthma risk under any genetic model. Meta-analysis of four studies on TLR2 Arg753Gln indicated that TLR2 might be significantly associated with asthma in the dominant and codominant models (P=0.029, P=0.030, and P=0.009, respectively). TLR9 -1237 was marginally associated with asthma risk (OR=0.408 [95% CI, 0.163-1.021; P=0.065]) in the codominant model. Analysis using the allele contrast model showed that the major TLR9 -1237 T allele tended to be a significant protective factor with OR=0.689 (95% CI, 0.471-1.007; P=0.055). Conclusions The results showed that TLR4 Asp299Gly, TLR2 Arg753Gln, and TLR9-1237 might contribute significantly to asthma susceptibility. Future genetic association studies would consolidate these findings.
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Affiliation(s)
- Kalthoum Tizaoui
- Division of Histology and Immunology, Department of Basic Sciences, Faculty of medicine Tunis, Tunis El Manar University, Tunis, Tunisia
| | - Wajih Kaabachi
- Division of Histology and Immunology, Department of Basic Sciences, Faculty of medicine Tunis, Tunis El Manar University, Tunis, Tunisia
| | - Kamel Hamzaoui
- Division of Histology and Immunology, Department of Basic Sciences, Faculty of medicine Tunis, Tunis El Manar University, Tunis, Tunisia
| | - Agnès Hamzaoui
- Division of Histology and Immunology, Department of Basic Sciences, Faculty of medicine Tunis, Tunis El Manar University, Tunis, Tunisia. ; Division of Pulmonology, Unit research: 1 2 SP15"Homeostasis and Cell Immune Dysfunction", A. Mami Hospital, Ariana, Tunisia
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9
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Shikhagaie MM, Andersson CK, Mori M, Kortekaas Krohn I, Bergqvist A, Dahl R, Ekblad E, Hoffmann HJ, Bjermer L, Erjefält JS. Mapping of TLR5 and TLR7 in central and distal human airways and identification of reduced TLR expression in severe asthma. Clin Exp Allergy 2014; 44:184-96. [PMID: 24447081 DOI: 10.1111/cea.12176] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Revised: 06/30/2013] [Accepted: 07/02/2013] [Indexed: 12/19/2022]
Abstract
BACKGROUND The toll-like receptors, TLR5 and TLR7, have recently been proposed in asthma immunopathogenesis. While supporting data come from animal or in vitro studies, little is known about TLR5 and TLR7 expression in human asthmatic airways. METHODS Advanced immunohistochemical mapping of TLR5 and TLR7 was performed on bronchial and transbronchial biopsies from healthy individuals and patients with moderate and severe asthma. RESULTS TLR5 was identified in multiple structural cells; bronchial epithelium, alveolar type II pneumocytes, plasma cells, macrophages and neutrophils. Contrary to bronchial TLR5, which had a basolateral expression, alveolar TLR5 had polarized apical localization. Patients with severe asthma had decreased total and epithelial TLR5 expression compared to controls and moderate asthmatics (P < 0.001). TLR7 expression was found in several structural cells and asthma-related immune cells. Whereas TLR7 expression was decreased in severe asthmatics (P < 0.001), nerve-associated TLR7 increased (P = 0.035). Within the asthma groups, both TLR5 and TLR7 expression correlated with multiple lung function parameters. CONCLUSIONS Our results reveal broad expression patterns of TLR5 and TLR7 in the lung and that the expression is decreased in severe asthma. Hence, severe asthmatics may suffer from insufficient TLR signalling during viral or bacterial infections leading to poor and impaired defence mechanisms.
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Affiliation(s)
- M M Shikhagaie
- Department of Experimental Medical Science, Lund University, Lund, Sweden
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10
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The association of genetic variants in toll-like receptor 2 subfamily with allergy and asthma after hospitalization for bronchiolitis in infancy. Pediatr Infect Dis J 2014; 33:463-6. [PMID: 24445834 DOI: 10.1097/inf.0000000000000253] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Toll-like receptors (TLRs) are a pivotal part of the innate immunity system. Variations in TLR genes have been connected to autoimmune conditions, such as allergy and asthma. The TLR2 subfamily comprises TLR1, TLR2, TLR6 and TLR 10. We hypothesized that polymorphism of the TLR2 subfamily may be associated with prevalence of post-bronchiolitic asthma and/or atopy. METHODS TLR1rs5743618, TLR2rs5743708 and TLR6rs5743810 single nucleotide polymorphisms of 133 children who had been hospitalized for bronchiolitis at <6 months of age were analyzed. Doctor-diagnosed asthma and atopy as well as their occurrence during the first 6 years of life were evaluated during a follow-up visit. RESULTS At the mean age of 6.4 years, asthma was present in 17 (13%) patients, there was asthma diagnosis during the first 6 years of life in 39 (29%) and current doctor-diagnosed allergic rhinitis in 57 (43%) patients. Twenty-four (24%) children with G/G genotype in TLR1 rs5743618 were diagnosed to have asthma between 1 and 6 years of age (vs. 13 (38%) of those with G/T or T/T genotypes; P = 0.04). In addition, 11/60 (18%) children with TLR6 rs5743810 C/T versus 36/73 (49%) children of other genotypes had atopic eczema at follow up. Only 2 children (8%) with wild genotype in all investigated single nucleotide polymorphisms had asthma during the first 6 years of life (vs. 30% in those with variant genotype of TLR1, TLR2 and/or TLR6). CONCLUSION In this study, we demonstrated that TLR1 rs5743618 was associated with asthma and atopic eczema during the first 6 years of life after early bronchiolitis. In addition, TLR6 rs5743810 was associated with present atopy at preschool age.
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11
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Overview and outlook of Toll-like receptor ligand–antigen conjugate vaccines. Ther Deliv 2012; 3:749-60. [DOI: 10.4155/tde.12.52] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
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12
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Kovach MA, Standiford TJ. Toll like receptors in diseases of the lung. Int Immunopharmacol 2011; 11:1399-406. [PMID: 21624505 PMCID: PMC3575025 DOI: 10.1016/j.intimp.2011.05.013] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2011] [Revised: 05/11/2011] [Accepted: 05/12/2011] [Indexed: 12/16/2022]
Abstract
The lung is in continuous contact with a diverse array of infectious agents, foreign antigens, and host-derived danger signals. To sample this expansive internal and external milieu, both resident myeloid and stromal/structure cells of the lung express a full complement of toll like receptors (TLRs) which recognize pathogen-associated molecular patterns (PAMPs) and endogenous danger-associated molecular patterns (DAMPs). TLRs play a vital role in immune host defense against bacterial, mycobacterial, fungal, and viral pathogens of the lung. Additionally, TLRs contribute to disease pathogenesis in non-infectious pulmonary disorders, including airway disease, acute lung injury, and interstitial lung disease. In this review, TLR biology in the context of experimental infectious and non-infectious lung disease is discussed, and correlates to human lung disease, including therapeutic implications of these findings, are defined.
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Affiliation(s)
- Melissa A Kovach
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor, MI 48109, United States
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