Panel 8: Report on Recent Advances in Molecular and Cellular Biochemistry

Abstract

Objectives. To update the medical literature on recent cellular and molecular advances in otitis media disease models with a principal focus on developments in the past 5 years. We also aim to explain recent translational advances in cellular and molecular biology that have influenced our understanding and management of otitis media.Data Sources. PubMed-indexed peer-reviewed articles.Review Methods. A comprehensive review of the literature was conducted with the term otitis media and the following search terms: molecular biology, cell biology, innate immunity, oxidative stress, mucins, molecular diagnostics. Included articles were published in the English language from January 1, 2010, to July 31, 2015.Implications for Practice. The molecular understanding of otitis media disease progression has rapidly advanced over the last 5 years. The roles of inflammation, mucins, and cell signaling mechanisms have been elucidated and defined. Advances in the field provide a plethora of opportunities for innovative molecular targeting in the development of novel therapeutic strategies for otitis media. I nfections in the middle ear trigger a series of cellular responses in middle ear epithelium. The subsequent pathogenesis of otitis media (OM) from acute to chronic, however, is complex and multifactorial. Mechanisms of propensity to OM have been shown to involve, among many other factors, mutations or polymorphisms in genes that mediate innate immunity and cellular signaling pathways that promote healing and recovery after inflammation. According to recent reports, the following cellular signaling pathways are altered following OM infection: Toll-like receptor (TLR) cascade, the inflammasome, NF-kB signaling, and the TGF-b pathway. During disease progression, mucous cell metaplasia or hyperplasia is frequently observed in animal models and human tissue specimens. In turn, the occurrence of mucous cell metaplasia or hyperplasia promotes the chronicity of OM as well as relapses of acute infections due to the abundant production of mucin glycoproteins. This State of the Art Review updates recent advances in innate immune and cell signaling responses, genetic predispositions that affect molecular pathways, mucin responses, oxidative stress, and novel molecular diagnostics. MethodsA comprehensive review of the medical literature was conducted by the Panel 8 members of the Post-Conference

Innate Immunity in the Middle Ear Mucosa

“…The innate immune system is a critical first line of defence within the middle ear and is activated in response to pathogen associated molecular patterns (PAMPs) on invading pathogens (Li et al, 2013;Massa et al, 2015). Key characteristics of this defence mechanism include physical epithelial barriers, recognition of non-self-factors such as pathogens, upregulation of the complement system, initiation of generalised inflammatory responses and activation of specific immune responses to pathogens through upregulation of the adaptive immune system (Massa et al, 2015;Preciado et al, 2017).…”