title: Proteomic Characterization of Middle Ear Fluid Confirms Neutrophil Extracellular Traps as a Predominant Innate Immune Response in Chronic Otitis Media.
abstract: BACKGROUND
  Chronic Otitis Media (COM) is characterized by middle ear effusion (MEE) and conductive hearing loss. MEE reflect mucus hypersecretion, but global proteomic profiling of the mucosal components are limited.
  
  
  OBJECTIVE
  This study aimed at characterizing the proteome of MEEs from children with COM with the goal of elucidating important innate immune responses.
  
  
  METHODS
  MEEs were collected from children (n = 49) with COM undergoing myringotomy. Mass spectrometry was employed for proteomic profiling in nine samples. Independent samples were further analyzed by cytokine multiplex assay, immunoblotting, neutrophil elastase activity, next generation DNA sequencing, and/or immunofluorescence analysis.
  
  
  RESULTS
  109 unique and common proteins were identified by MS. A majority were innate immune molecules, along with typically intracellular proteins such as histones and actin. 19.5% percent of all mapped peptide counts were from proteins known to be released by neutrophils. Immunofluorescence and immunoblotting demonstrated the presence of neutrophil extracellular traps (NETs) in every MEE, along with MUC5B colocalization. DNA found in effusions revealed unfragmented DNA of human origin.
  
  
  CONCLUSIONS
  Proteomic analysis of MEEs revealed a predominantly neutrophilic innate mucosal response in which MUC5B is associated with NET DNA. NETs are a primary macromolecular constituent of human COM middle ear effusions.
authors.affiliation: Sheikh Zayed Center for Pediatric Surgical Innovation, Children's National Health System, Washington, DC, United States of America.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Val
authors.affiliation: Sheikh Zayed Center for Pediatric Surgical Innovation, Children's National Health System, Washington, DC, United States of America.
authors.forename: Marian
authors.initials: M
authors.lastname: Poley
authors.affiliation: Center for Genetic Medicine Research, Children's National Health System, Washington, DC, United States of America.
authors.forename: Kristy
authors.initials: K
authors.lastname: Brown
authors.affiliation: Sheikh Zayed Center for Pediatric Surgical Innovation, Children's National Health System, Washington, DC, United States of America.
authors.forename: Rachel
authors.initials: R
authors.lastname: Choi
authors.affiliation: Sheikh Zayed Center for Pediatric Surgical Innovation, Children's National Health System, Washington, DC, United States of America.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Jeong
authors.affiliation: Center for Genetic Medicine Research, Children's National Health System, Washington, DC, United States of America.
authors.forename: Annie
authors.initials: A
authors.lastname: Colberg-Poley
authors.affiliation: Center for Genetic Medicine Research, Children's National Health System, Washington, DC, United States of America.
authors.forename: Mary C
authors.initials: MC
authors.lastname: Rose
authors.affiliation: Center for Genetic Medicine Research, Children's National Health System, Washington, DC, United States of America.
authors.forename: Karuna C
authors.initials: KC
authors.lastname: Panchapakesan
authors.affiliation: Center for Genetic Medicine Research, Children's National Health System, Washington, DC, United States of America.
authors.forename: Joe C
authors.initials: JC
authors.lastname: Devaney
authors.affiliation: Center for Genetic Medicine Research, Children's National Health System, Washington, DC, United States of America.
authors.forename: Marcos
authors.initials: M
authors.lastname: Perez-Losada
authors.affiliation: Sheikh Zayed Center for Pediatric Surgical Innovation, Children's National Health System, Washington, DC, United States of America.|Division of Pediatric Otolaryngology, Children's National Health System, Washington, DC, United States of America.
authors.forename: Diego
authors.identifier: http://orcid.org/0000-0003-0075-8279
authors.initials: D
authors.lastname: Preciado
mesh_terms: D002675:Child, Preschool; D002908:Chronic Disease; D065206:Extracellular Traps / Q000276:immunology* / Q000378:metabolism; D005260:Female; D006801:Humans; D007113:Immunity, Innate; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009504:Neutrophils / Q000166:cytology*; D010034:Otitis Media with Effusion / Q000276:immunology* / Q000378:metabolism*; D040901:Proteomics