Metagenomic Analysis of the Lung Microbiome in Chemically Injured and Healthy Individuals

Document Type : Original Research

Authors

1 Human Genetics Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran.

2 Chemical Injuries Research Center, Baqiyatallah University of Medical sciences, Tehran, Iran.

3 Human Genetics Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran

Abstract

Background and Aim: The role of the lung microbiome in respiratory complications associated with chemicals such as sulfur mustard or chlorine gas has yet to be determined. The aim of this study was to compare the structure and composition of the lung microbiome in chemically injured and healthy individuals in order to understand the relation between the population of the lung microbiota and respiratory complications caused by exposure to these chemicals.
Methods: To study lung microbiota, the bronchial alveolar lavage (BAL) fluids were collected from 17 chemically injured and 15 healthy cases during the bronchoscopy procedure. The diversity of lung bacteria present in BAL samples was explored using 16S rRNA gene sequencing.
Results: The lung microbiome dominated by members of phyla Firmicutes, Bacteroidetes, Proteobacteria, Actinobacteria, Fusobacteria and Synergistetes which collectively accounted for > 95% of sequences. At the genus level, members of the genera Prevotella, Leptotrichia, Atopobium, Aggregatibacter, Catonella, and Oribacterium showed more than 2-fold increase in abundance in the lung microbiome of chemically injured patients. Comparing lung bacterial community at the species level, however, revealed an increased prevalence of members of Rothia mucilaginosa (3-fold), Prevotella melaninogenica (2.7-fold), Prevotella pallens (3.5-fold), Actinobacillus parahaemolyticus (2.5-fold), Veillonella parvula (2.5-fold), and Neisseria subflava (1.5-fold) in these patients.
Conclusion: An increased abundance of bacterial species known to associate with airway inflammation suggested their implications in respiratory failure in chemically injured patients. Monitoring and maintaining the homeostasis of the microbial population colonizing lung of chemically injured patients will pave the way to develop a more targeted treatment for these patients.

Keywords


1. Ghanei M, Harandi AA. Molecular and cellular mechanism of lung injuries due to exposure to sulfur mustard: a review. Inhal Toxicol. 2011;23(7):363-71. doi:10.3109/08958378.2011.576278 2. Ghanei M, Harandi AA. Long term consequences from exposure to sulfur mustard: a review. Inhal Toxicol. 2007;19(5):451-6. doi:10.1080/08958370601174990 3. Ghanei M, Fathi H, Mohammad MM, Aslani J, Nematizadeh F. Long-term respiratory disorders of claimers with subclinical exposure to chemical warfare agents. Inhal Toxicol. 2004;16(8):491-5. doi:10.1080/08958370490442421 4. Ghanei M, Mokhtari M, Mohammad MM, Aslani J. Bronchiolitis obliterans following exposure to sulfur mustard: chest high resolution computed tomography. Eur J Radiol. 2004;52(2):164-9. doi:10.1016/j.ejrad.2004.03.018 5. Hilty M, Burke C, Pedro H, Cardenas P, Bush A, Bossley C, et al. Disordered microbial communities in asthmatic airways. PLoS One. 2010;5(1):e8578. doi:10.1371/journal.pone.0008578 6. Charlson ES, Bittinger K, Haas AR, Fitzgerald AS, Frank I, Yadav A, et al. Topographical continuity of bacterial populations in the healthy human respiratory tract. Am J Respir Crit Care Med. 2011;184(8):957-63. doi:10.1164/rccm.201104-0655OC 7. Cabrera-Rubio R, Garcia-Nunez M, Seto L, Anto JM, Moya A, Monso E, et al. Microbiome diversity in the bronchial tracts of patients with chronic obstructive pulmonary disease. J Clin Microbiol. 2012;50(11):3562-8. doi:10.1128/JCM.00767-12 8. Kim HJ, Kim YS, Kim KH, Choi JP, Kim YK, Yun S, et al. The microbiome of the lung and its extracellular vesicles in nonsmokers, healthy smokers and COPD patients. Exp Mol Med. 2017;49(4):e316. doi:10.1038/emm.2017.7 9. Frayman KB, Armstrong DS, Carzino R, Ferkol TW, Grimwood K, Storch GA, et al. The lower airway microbiota in early cystic fibrosis lung disease: a longitudinal analysis. Thorax. 2017;72 (12):1104-12. doi: 10.1136/thoraxjnl-2016-209279 10. Chung KF. Airway microbial dysbiosis in asthmatic patients: A target for prevention and treatment? J Allergy Clin Immunol. 2017;139(4): 1071-81. doi:10.1016/j.jaci.2017.02.004 11. Molyneaux PL, Cox MJ, Wells AU, Kim HC, Ji W, Cookson WO, et al. Changes in the respiratory microbiome during acute exacerbations of idiopathic pulmonary fibrosis. Respir Res. 2017;18(1):29. doi:10.1186/s12931-017-0511-3 12. Scher JU, Joshua V, Artacho A, Abdollahi-Roodsaz S, Ockinger J, Kullberg S, et al. The lung microbiota in early rheumatoid arthritis and autoimmunity. Microbiome. 2016;4(1):60. doi:10.1186/s40168-016-0206-x 13. Dickson RP, Huffnagle GB. The Lung Microbiome: New Principles for Respiratory Bacteriology in Health and Disease. PLoS Pathog. 2015;11(7):e1004923. doi:10.1371/journal.ppat.1004923 14. Segal LN, Alekseyenko AV, Clemente JC, Kulkarni R, Wu B, Chen H, et al. Enrichment of lung microbiome with supraglottic taxa is associated with increased pulmonary inflammation. Microbiome. 2013;1(1):19. doi:10.1186/2049-2618-1-19 15. Byun MK, Chang J, Kim HJ, Jeong SH. Differences of lung microbiome in patients with clinically stable and exacerbated bronchiectasis. PLoS One. 2017;12(8):e0183553. doi:10.1371/journal.pone.0183553 16. Zemanick ET, Sagel SD, Harris JK. The airway microbiome in cystic fibrosis and implications for treatment. Curr Opin Pediatr. 2011;23(3):319-24. doi:10.1097/MOP.0b013e32834604f2 17. Beck JM, Young VB, Huffnagle GB. The microbiome of the lung. Transl Res. 2012;160(4): 258-66. doi:10.1016/j.trsl.2012.02.005 18. Hang J, Zavaljevski N, Yang Y, Desai V, Ruck RC, Macareo LR, et al. Composition and variation of respiratory microbiota in healthy military personnel. PLoS One. 2017;12(12):e0188461. doi:10.1371/journal.pone.0188461 19. Magoc T, Salzberg SL. FLASH: fast length adjustment of short reads to improve genome assemblies. Bioinformatics. 2011;27(21):2957-63. doi:10.1093/bioinformatics/btr507 20. Caporaso JG, Kuczynski J, Stombaugh J, Bittinger K, Bushman FD, Costello EK, et al. QIIME allows analysis of high-throughput community sequencing data. Nat Methods. 2010;7(5):335-6. doi:10.1038/nmeth.f.303 21. Rognes T, Flouri T, Nichols B, Quince C, Mahe F. VSEARCH: a versatile open source tool for metagenomics. Peer J. 2016;4:e2584. doi:10.7717/peerj.2584 22. Gharechahi J, Kharazian ZA, Sarikhan S, Jouzani GS, Aghdasi M, Hosseini Salekdeh G. The dynamics of the bacterial communities developed in maize silage. Microb Biotechnol. 2017;10(6):1663-76. doi:10.1111/1751-7915.12751 23. Cox MJ, Allgaier M, Taylor B, Baek MS, Huang YJ, Daly RA, et al. Airway microbiota and pathogen abundance in age-stratified cystic fibrosis patients. PLoS One. 2010;5(6):e11044. doi:10.1371/journal.pone.0011044 24. Segal LN, Clemente JC, Tsay JC, Koralov SB, Keller BC, Wu BG, et al. Enrichment of the lung microbiome with oral taxa is associated with lung inflammation of a Th17 phenotype. Nat Microbiol. 2016;1:16031. doi:10.1038/nmicrobiol.2016.31 25. Wang J, Li F, Tian Z. Role of microbiota on lung homeostasis and diseases. Sci China Life Sci. 2017; 60 (12):1407-15.doi:10.1007/s11427-017-9151-1 26. Sze MA, Dimitriu PA, Hayashi S, Elliott WM, McDonough JE, Gosselink JV, et al. The lung tissue microbiome in chronic obstructive pulmonary disease. Am J Respir Crit Care Med. 2012;185 (10):1073-80. doi:10.1164/rccm.201111-2075OC 27. Bisgaard H, Hermansen MN, Buchvald F, Loland L, Halkjaer LB, Bonnelykke K, et al. Childhood asthma after bacterial colonization of the airway in neonates. N Engl J Med. 2007;357(15):1487-95. doi:10.1056/NEJMoa052632 28. Erb-Downward JR, Thompson DL, Han MK, Freeman CM, McCloskey L, Schmidt LA, et al. Analysis of the lung microbiome in the "healthy" smoker and in COPD. PLoS One. 2011;6(2):e16384. doi:10.1371/journal.pone.0016384 29. Morris A, Beck JM, Schloss PD, Campbell TB, Crothers K, Curtis JL, et al. Comparison of the respiratory microbiome in healthy nonsmokers and smokers. Am J Respir Crit Care Med. 2013;187 (10):1067-75. doi:10.1164/rccm.201210-1913OC 30. Aas JA, Paster BJ, Stokes LN, Olsen I, Dewhirst FE. Defining the normal bacterial flora of the oral cavity. J Clin Microbiol. 2005;43(11):5721-32. doi:10.1128/JCM.43.11.5721-5732.2005 31. Tunney MM, Field TR, Moriarty TF, Patrick S, Doering G, Muhlebach MS, et al. Detection of anaerobic bacteria in high numbers in sputum from patients with cystic fibrosis. Am J Respir Crit Care Med. 2008;177(9):995-1001. doi:10.1164/rccm.200708-1151OC