Utilization of Nasal Mucus to Investigate the Pathophysiology of Chronic Rhinosinusitis

Abstract

Background Nasal mucus is proving to be a useful means by which to study the pathogenesis of chronic rhinosinusitis (CRS). Given the increase in publications examining nasal mucus and the lack of a review on this topic, we will focus on this noninvasive approach to studying CRS. Particular attention will be drawn towards inflammatory cytokines and biomarkers and their influence on disease severity. Methods A literature review of papers published in English pertaining to nasal mucus was performed using the PubMed database. The search utilized combinations of the following keywords: sinusitis, polyps, sample collection, nasal mucus, or nasal secretion. Studies solely on acute or bacterial sinusitis, allergic rhinitis, or cystic fibrosis were not included. Results A wide variety of materials and methods have been used to collect nasal mucus. Numerous assay types have been performed with the most common being ELISA, cytometric bead array, and proteomics. Most studies have focused on examining the levels of Th1/Th2 cytokines along with chemokines associated with type 2 immunity. Other factors identified include growth factors, senescence-associated proteins, complement, and antimicrobial defenses have also been identified. Nasal mucus cytokines have proven useful in cluster analysis and predicting postoperative improvement in Sino-nasal Outcome Test (SNOT-22) scores. One limitation of the use of nasal mucus is that some studies have suggested that nasal mucus does not always reflect the tissue microenvironment. Conclusions Nasal mucus represents a critical tool by which to examine the sinonasal microenvironment in a noninvasive manner. Unlike studies of tissue, it can be utilized in both surgically and medically managed patients and avoids the trauma of biopsies. However, studies are still needed to determine the most effective method for nasal mucus collection. Studies should also take care to confirm that nasal mucus markers do, in fact, reflect the levels of the product studied in the tissue.

Roles of Exosomes in Chronic Rhinosinusitis: A Systematic Review

“…The isolation of exosomes from NLF or mucus in diagnostics of CRS can be a good alternative for tissue sampling because this method is effective, minimally invasive, easy, and possible to carry out without anesthesia and damage to the mucosa [ 24 ]. It should be noted that the most common technique of exosome isolation is UC [ 9 , 10 , 33 , 34 , 135 ], but this method is time-consuming and requires costly equipment [ 136 ], even though the content of proteins in the entire NM was the subject of studies concerning CRS [ 137 , 138 , 139 , 140 , 141 ]. Whole mucus does not reflect underlying tissue proteomes, as well as exosomal proteins, which are protected from degradation by nucleases and proteases, and their analysis is more reflective of the protein milieu of the host cell [ 15 ].…”

Recent advances in mass spectrometry-based proteomics and metabolomics in chronic rhinosinusitis with nasal polyps

“…Mucus can be obtained in several ways, Parra-Ferro et al. summarized the methods used for nasal mucus collection in recent years and discussed the advantages and shortcomings of each method ( 20 ). Polyurethane foam, commonly used for mucus collection, has a high secretion and protein recovery ( 21 ).…”

All chronic rhinosinusitis endotype clusters demonstrate improvement in patient‐reported and clinical outcome measures after endoscopic sinus surgery

“…8,9 As we enter the era of personalized medicine for CRS, biologics and other targeted therapies show substantial promise, but comparative efficacy among ideal target populations is currently unclear. 6,8,[10][11][12] The effectiveness of biologics is also highly variable and currently limited to patients with CRSwNP. 10,12 There is ongoing discussion on the role of endotyping and how it can be used to guide clinical care given available outcomes data for medical and surgical treatment options.…”

“…As we enter the era of personalized medicine for CRS, biologics and other targeted therapies show substantial promise, but comparative efficacy among ideal target populations is currently unclear 6,8,10–12 . The effectiveness of biologics is also highly variable and currently limited to patients with CRSwNP 10,12 .…”