Biomaterial Database

Candidate Role for Toll-like Receptor 3 L412F Polymorphism and Infection in Acute Exacerbation of Idiopathic Pulmonary Fibrosis. 2022

Aoife N McElroy, and Rachele Invernizzi, and Joanna W Laskowska, and Andrew O'Neill, and Mohammad Doroudian, and Mohsen Moghoofei, and Shayan Mostafaei, and Feng Li, and Alexander A Przybylski, and David N O'Dwyer, and Andrew G Bowie, and Padraic G Fallon, and Toby M Maher, and Cory M Hogaboam, and Philip L Molyneaux, and Nik Hirani, and Michelle E Armstrong, and Seamas C Donnelly

School of Medicine, Trinity Biomedical Sciences Institute, Trinity College, Dublin, Ireland.

Rationale: The Toll-like receptor 3 Leu412Phe (TLR3 L412F) polymorphism attenuates cellular antiviral responses and is associated with accelerated disease progression in idiopathic pulmonary fibrosis (IPF). The role of TLR3 L412F in bacterial infection in IPF or in acute exacerbations (AE) has not been reported. Objectives: To characterize the association between TLR3 L412F and AE-related death in IPF. To determine the effect of TLR3 L412F on the lung microbiome and on antibacterial TLR responses of primary lung fibroblasts from patients with IPF. Methods: TLR-mediated antibacterial and antiviral responses were quantitated in L412F wild-type and 412F-heterozygous primary lung fibroblasts from patients with IPF using ELISA, Western blot analysis, and quantitative PCR. Hierarchical heatmap analysis was employed to establish bacterial and viral clustering in nasopharyngeal lavage samples from patients with AE-IPF. 16S ribosomal RNA quantitative PCR and pyrosequencing were used to determine the effect of TLR3 L412F on the IPF lung microbiome. Measurements and Main Results: A significant increase in AE-related death in patients with 412F-variant IPF was reported. We established that 412F-heterozygous IPF lung fibroblasts have reduced antibacterial TLR responses to LPS (TLR4), Pam3CYSK4 (TLR1/2), flagellin (TLR5), and FSL-1 (TLR6/1) and have reduced responses to live Pseudomonas aeruginosa infection. Using 16S ribosomal RNA sequencing, we demonstrated that 412F-heterozygous patients with IPF have a dysregulated lung microbiome with increased frequencies of Streptococcus and Staphylococcus spp. Conclusions: This study reveals that TLR3 L412F dysregulates the IPF lung microbiome and reduces the responses of IPF lung fibroblasts to bacterial TLR agonists and live bacterial infection. These findings identify a candidate role for TLR3 L412F in viral- and bacterial-mediated AE death.

UI	MeSH Term	Description	Entries
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000900	Anti-Bacterial Agents	Substances that inhibit the growth or reproduction of BACTERIA.	Anti-Bacterial Agent,Anti-Bacterial Compound,Anti-Mycobacterial Agent,Antibacterial Agent,Antibiotics,Antimycobacterial Agent,Bacteriocidal Agent,Bacteriocide,Anti-Bacterial Compounds,Anti-Mycobacterial Agents,Antibacterial Agents,Antibiotic,Antimycobacterial Agents,Bacteriocidal Agents,Bacteriocides,Agent, Anti-Bacterial,Agent, Anti-Mycobacterial,Agent, Antibacterial,Agent, Antimycobacterial,Agent, Bacteriocidal,Agents, Anti-Bacterial,Agents, Anti-Mycobacterial,Agents, Antibacterial,Agents, Antimycobacterial,Agents, Bacteriocidal,Anti Bacterial Agent,Anti Bacterial Agents,Anti Bacterial Compound,Anti Bacterial Compounds,Anti Mycobacterial Agent,Anti Mycobacterial Agents,Compound, Anti-Bacterial,Compounds, Anti-Bacterial
D000998	Antiviral Agents	Agents used in the prophylaxis or therapy of VIRUS DISEASES. Some of the ways they may act include preventing viral replication by inhibiting viral DNA polymerase; binding to specific cell-surface receptors and inhibiting viral penetration or uncoating; inhibiting viral protein synthesis; or blocking late stages of virus assembly.	Antiviral,Antiviral Agent,Antiviral Drug,Antivirals,Antiviral Drugs,Agent, Antiviral,Agents, Antiviral,Drug, Antiviral,Drugs, Antiviral
D012336	RNA, Ribosomal, 16S	Constituent of 30S subunit prokaryotic ribosomes containing 1600 nucleotides and 21 proteins. 16S rRNA is involved in initiation of polypeptide synthesis.	16S Ribosomal RNA,16S rRNA,RNA, 16S Ribosomal,Ribosomal RNA, 16S,rRNA, 16S
D051196	Toll-Like Receptor 3	A pattern recognition receptor that binds DOUBLE-STRANDED RNA. It mediates cellular responses to certain viral pathogens.	TLR3 Receptor,Receptor, TLR3,Toll Like Receptor 3
D054990	Idiopathic Pulmonary Fibrosis	A common interstitial lung disease of unknown etiology, usually occurring between 50-70 years of age. Clinically, it is characterized by an insidious onset of breathlessness with exertion and a nonproductive cough, leading to progressive DYSPNEA. Pathological features show scant interstitial inflammation, patchy collagen fibrosis, prominent fibroblast proliferation foci, and microscopic honeycomb change.	Cryptogenic Fibrosing Alveolitis,Familial Idiopathic Pulmonary Fibrosis,Fibrocystic Pulmonary Dysplasia,Fibrosing Alveolitis, Cryptogenic,Idiopathic Fibrosing Alveolitis, Chronic Form,Idiopathic Pulmonary Fibrosis, Familial,Interstitial Pneumonitis, Usual,Pulmonary Fibrosis, Idiopathic,Usual Interstitial Pneumonia,Cryptogenic Fibrosing Alveolitides,Dysplasia, Fibrocystic Pulmonary,Fibrocystic Pulmonary Dysplasias,Fibrosing Alveolitides, Cryptogenic,Idiopathic Pulmonary Fibroses,Interstitial Pneumonia, Usual,Pneumonitides, Usual Interstitial,Pneumonitis, Usual Interstitial,Pulmonary Dysplasia, Fibrocystic,Pulmonary Fibroses, Idiopathic,Usual Interstitial Pneumonias,Usual Interstitial Pneumonitides,Usual Interstitial Pneumonitis
D018450	Disease Progression	The worsening and general progression of a disease over time. This concept is most often used for chronic and incurable diseases where the stage of the disease is an important determinant of therapy and prognosis.	Clinical Course,Clinical Progression,Disease Exacerbation,Exacerbation, Disease,Progression, Clinical,Progression, Disease