PLX112509

GSE113210: Acute viral bronchiolitis (PBMC)

• Organsim human
• Type RNASEQ
• Target gene
• Project ARCHS4

Background: A subset of infants are hyper-susceptible to severe/acute viral bronchiolitis (AVB), for reasons unknown.; Purpose: To characterise the cellular/molecular mechanisms underlying infant AVB in circulating cells/local airways tissues.; Methods: PBMC and nasal mucosal scrapings (NMS) were obtained from Infants (<18mths) and children (1.5-5yrs) during AVB and post-convalescence. Immune response patterns were profiled by multiplex analysis of plasma cytokines, flow cytometry, and transcriptomics (RNA-Seq). Molecular profiling of group-level data utilised a combination of upstream regulator and coexpression network analysis, followed by individual subject-level data analysis employing personalised N-of-1-pathways methodology.; Results: Group-level analyses demonstrated that infant PBMC responses were dominated by monocyte-associated hyper-upregulated type I interferon signalling/pro-inflammatory pathways (drivers: TNF, IL6, TREM1, IL1B), versus a combination of inflammation (PTGER2, IL6) plus growth/repair/remodelling pathways (ERBB2, TGFB1, AREG, HGF) coupled with Th2 and NK-cell signalling in children. Age-related differences were not attributable to differential steroid usage or variations in underlying viral pathogens. Nasal mucosal responses were comparable qualitatively in infants/children, dominated by interferon types I-III, but the magnitude of upregulation was higher in infants (range 6-48-fold) than children (5-17-fold). N-of-1-pathways analysis confirmed differential upregulation of innate immunity in infants and NK cell networks in children, and additionally demonstrated covert AVB response sub-phenotypes that were independent of chronological age.; Conclusions: Dysregulated expression of interferon-dependent pathways following respiratory viral infections is a defining immunophenotypic feature of AVB-susceptible infants and a subset of children. Susceptible subjects appear to represent a discrete subgroup who cluster based on (slow) kinetics of postnatal maturation of innate immune competence. SOURCE: Anya Jones (Anya.Jones@telethonkids.org.au) - Systems Immunology Telethon Kids Institute, The University of Western Australia