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

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a complex and heterogeneous disease, typically diagnosed through endoscopy and computed tomography and treated with glucocorticoid or surgery. There is an urgent need to develop molecular-level diagnostic or prognostic tools to better understand the pathophysiology of CRSwNP. Proteomics and metabolomics, emerging fields, offer significant potential in elucidating the mechanisms underlying CRSwNP. Mass spectrometry, a powerful and sensitive tool for trace substance detection, is broadly applied for proteomics and metabolomics analysis in CRSwNP research. While previous literature has summarized the advancement of mass spectrometry-based CRSwNP proteomics from 2004 to 2018, recent years have seen new advances in this field, particularly about non-invasive samples and exosomes. Furthermore, mass spectrometry-based CRSwNP metabolomics research has opened new avenues for inquiry. Therefore, we present a comprehensive review of mass spectrometry-based proteomics and metabolomics studies on CRSwNP conducted between 2019 and 2022. Specifically, we highlight protein and metabolic biomarkers that have been utilized as diagnostic or prognostic markers for CRSwNP. Lastly, we conclude with potential directions for future mass spectrometry-based omics studies of CRSwNP.

Novel 3D-printed hollow microneedles facilitate safe, reliable, and informative sampling of perilymph from guinea pigs

BACKGROUND

Inner ear diagnostics is limited by the inability to atraumatically obtain samples of inner ear fluid. The round window membrane (RWM) is an attractive portal for accessing perilymph samples as it has been shown to heal within one week after the introduction of microperforations. A 1 µL volume of perilymph is adequate for proteome analysis, yet the total volume of perilymph within the scala tympani of the guinea pig is limited to less than 5 µL. This study investigates the safety and reliability of a novel hollow microneedle device to aspirate perilymph samples adequate for proteomic analysis.

METHODS

The guinea pig RWM was accessed via a postauricular surgical approach. 3D-printed hollow microneedles with an outer diameter of 100 µm and an inner diameter of 35 µm were used to perforate the RWM and aspirate 1 µL of perilymph. Two perilymph samples were analyzed by liquid chromatography-mass spectrometry-based quantitative proteomics as part of a preliminary study. Hearing was assessed before and after aspiration using compound action potential (CAP) and distortion product otoacoustic emissions (DPOAE). RWMs were harvested 72 h after aspiration and evaluated for healing using confocal microscopy.

RESULTS

There was no permanent damage to hearing at 72 h after perforation as assessed by CAP (n = 7) and DPOAE (n = 8), and all perforations healed completely within 72 h (n = 8). In the two samples of perilymph analyzed, 620 proteins were detected, including the inner ear protein cochlin, widely recognized as a perilymph marker.

CONCLUSION

Hollow microneedles can facilitate aspiration of perilymph across the RWM at a quality and volume adequate for proteomic analysis without causing permanent anatomic or physiologic dysfunction. Microneedles can mediate safe and effective intracochlear sampling and show great promise for inner ear diagnostics.

Personalized Medicine in Respiratory Disease: Role of Proteomics

Respiratory diseases affect humanity globally, with chronic lung diseases (e.g., asthma, chronic obstructive pulmonary disease, idiopathic pulmonary fibrosis, among others) and lung cancer causing extensive morbidity and mortality. These conditions are highly heterogeneous and require an early diagnosis. However, initial symptoms are nonspecific, and the clinical diagnosis is made late frequently. Over the last few years, personalized medicine has emerged as a medical care approach that uses novel technology aiming to personalize treatments according to the particular patient's medical needs. This review highlights the contributions of proteomics toward the understanding of personalized medicine in respiratory disease and its potential applications in the clinic.

Respiratory proteomics: from descriptive studies to personalized medicine

Respiratory diseases are highly prevalent and affect humankind worldwide, causing extensive morbidity and mortality with the environment playing an important role. Given the complex structure of the airways, sophisticated tools are required for early diagnosis; initial symptoms are nonspecific, and the clinical diagnosis is made frequently late. Over the past few years, proteomics has made high technological progress in mass-spectrometry-based protein identification and has allowed us to gain new insights into disease mechanisms and identify potential novel therapeutic targets. This review will highlight the contributions of proteomics toward the understanding of the respiratory proteome listing potential biomarkers and its potential application to the clinic. We also outline the contributions of proteomics to creating a personalized approach in respiratory medicine.

Dysregulated survivin expression in nasal polyps of individuals with aspirin exacerbated respiratory disease

BACKGROUND

A derailed balance of cell proliferation and apoptosis is presumed to result in cell hyperplasia as a typical feature of nasal polyps. Survivin, a protein of the inhibitors of the apoptosis family is proposed to promote polyp formation. However, studies concerning survivin expression in chronic rhinosinusitis (CRS) with nasal polyps are rare and the specificity of the survivin expression in nasal polyps from individuals with aspirin-exacerbated respiratory disease (AERD) has not been investigated.

METHODS

Immunohistochemical survivin expression analysis was performed. Samples were taken from the ethmoid sinus of individuals with CRS with nasal polyps with and without AERD during sinus surgery and control specimens of the inferior turbinate from individuals without CRS. Cell cultures were stimulated with recombinant vascular endothelial growth factor (VEGF(165)) and the resulting survivin expression was analyzed by Western blot.

RESULTS

The survivin expression of 61 specimens was analyzed by quantitative immunohistochemistry and a potential VEGF-dependant stimulation of survivin in cell cultures was investigated. The survivin expression in nasal polyps from individuals with AERD was increased compared with the controls (median, 1194 versus 927 arbitrary units [A.U.]; p = 0.054). Western blot analysis revealed in vitro a VEGF-dependant regulation of survivin in nasal polyps from individuals without AERD, but not in those with AERD (p = 0.05).

CONCLUSION

Enhanced survivin expression might result in decreased apoptosis and cellular hyperplasia as a part of the largely unknown pathophysiology of nasal polyp formation. Furthermore, we hypothesize a pathological, VEGF-independent constitutive survivin expression in nasal polyps of individuals with AERD.

Role of innate immunity in the pathogenesis of chronic rhinosinusitis: progress and new avenues

Chronic rhinosinusitis is a heterogeneous and multifactorial disease with unknown etiology. Aberrant responses to microorganisms have been suggested to play a role in the pathophysiology of the disease. Research has focused on the presence, detection, response to, and eradication of these potential threats. Main topics seem to center on the contribution of structural cells such as epithelium and fibroblasts, on the consequences of activation of pattern-recognition receptors, and on the role of antimicrobial agents. This research should be viewed not only in the light of a comparison between healthy and diseased individuals, but also in a comparison between patients who do or do not respond to treatment. New players that could play a role in the pathophysiology seem to surface at regular intervals, adding to our understanding (and the complexity) of the disease and opening new avenues that may help fight this incapacitating disease.

Surfactant protein A and D in chronic rhinosinusitis with nasal polyposis and corticosteroid response

BACKGROUND

Corticosteroids are a mainstay of treatment for chronic rhinosinusitis with nasal polyposis (CRSwNP). Data related to the effect of systemic methylprednisolone on surfactant protein (SP) expression in CRSwNP is limited. This study aimed to reveal the consequences of systemic methylprednisolone treatment on levels of SP-A and SP-D, which play a role in innate immunity, in patients with CRSwNP.

METHODS

Twenty-one patients with CRSwNP were included in the study, along with 15 control patients scheduled for dacryocystorhinostomy. A polypoid tissue biopsy was taken under local anesthesia, and 15 CRSwNP patients were scheduled for endoscopic sinus surgery after 3 weeks of oral methylprednisolone. Posttreatment biopsies were performed perioperatively. Pre- and posttreatment endoscopic polyp grades were determined, as were symptom scores regarding nasal obstruction, headache, and nasal discharge using a visual analog scale (VAS). SP-A and SP-D levels were measured using enzyme-linked immunosorbent assay and the results were compared.

RESULTS

All patients reported relief from clinical symptoms through VAS after methylprednisolone treatment. The posttreatment polyp grade was reduced (p < 0.0001). SP-A and SP-D levels did not yield a significant difference between CRSwNP patients and controls (p = 0.25 and p = 0.13, respectively). Statistically significant up-regulation was detected in SP-A and SP-D levels after oral methylprednisolone (p = 0.0002 and p = 0.0004, respectively).

CONCLUSION

In this study, significant up-regulation of SP-A and SP-D was revealed in patients with CRSwNP after systemic steroid treatment. The role of SP-A and SP-D up-regulation in CRSwNP pathogenesis and therapeutic outcomes of corticosteroids have potential importance for the introduction of new therapeutic modalities that are more effective and produce fewer adverse effects.

Retinoic acid-inducible gene 1-like receptors in the upper respiratory tract

BACKGROUND

Retinoic acid-inducible gene 1-like receptors (RLRs) are a novel family of pattern recognition receptors that include retinoic acid-inducible gene 1 (RIG-1), melanoma differentiation-associated gene 5 (MDA-5), and laboratory of genomics and physiology 2 (LGP-2). The knowledge of RLRs and their function in the human airway is limited. This study explores the role of RLRs in the upper respiratory tract.

METHODS

Tonsils, adenoids, nasal polyps, and biopsy specimens from the nasal mucosa were examined for the occurrence of the RIG-1, MDA-5, and LGP-2 using real-time reverse-transcription polymerase chain reaction and immunohistochemistry. The nasopharyngeal epithelial cell line FaDu was cultured with the RIG-1/MDA-5 ligand poly(I:C)/LyoVec (Invivogen, San Diego, CA) and analyzed for cytokine release using ELISA.

RESULTS

RIG-1, MDA-5, and LGP-2 mRNA were found in all tissues tested. The airway epithelium appeared to be their most prominent location. The RIG-1 and MDA-5 mRNA levels were higher in nasal polyps than in normal nasal mucosa, a state that seemed to be reversed by local steroid treatment. Culture of FaDu with poly(I:C)/LyoVec resulted in IL-6 and IL-8 release. No alteration in RLR expression in tonsils was seen on infection.

CONCLUSION

This study shows the presence and functional activity of RLRs in the human upper airways. It also suggests a role for RLRs in nasal polyposis.

Fatty acid binding protein 1 is related with development of aspirin-exacerbated respiratory disease

Background

Aspirin-exacerbated respiratory disease (AERD) refers to the development of bronchoconstriction in asthmatics following the ingestion of aspirin. Although alterations in eicosanoid metabolites play a role in AERD, other immune or inflammatory mechanisms may be involved. We aimed to identify proteins that were differentially expressed in nasal polyps between patients with AERD and aspirin-tolerant asthma (ATA).

Methodology/Principal Findings

Two-dimensional electrophoresis was adopted for differential display proteomics. Proteins were identified by liquid chromatography-tandem mass spectrometry (LC-MS). Western blotting and immunohistochemical staining were performed to compare the amount of fatty acid-binding protein 1 (FABP1) in the nasal polyps of patients with AERD and ATA. Fifteen proteins were significantly up- (seven spots) or down-regulated in the nasal polyps of patients with AERD (n = 5) compared to those with ATA (n = 8). LC-MS revealed an increase in seven proteins expression and a decrease in eight proteins expression in patients with AERD compared to those with ATA (P = 0.003–0.045). FABP1-expression based on immunoblotting and immunohistochemical analysis was significantly higher in the nasal polyps of patients with AERD compared to that in patients with ATA. FABP1 was observed in epithelial, eosinophils, macrophages, and the smooth-muscle cells of blood vessels in the polyps.

Conclusions/Significance

Our results indicate that alterations in 15 proteins, including FABP1, may be related to the development of AERD.

Treatment of recurrent sinonasal polyposis with steroid-infused carboxymethylcellulose foam

BACKGROUND

Recurrence of sinonasal polyposis after endoscopic sinus surgery can be difficult to manage. Topical steroid sprays and irrigations may not provide adequate treatment and systemic steroid therapy is limited by side effects. This study was designed to evaluate the efficacy of steroid-infused carboxymethylcellulose (CMC) foam as a treatment for recurrence of chronic rhinosinusitis with nasal polyposis after endoscopic sinus surgery.

METHODS

A prospective cohort study was performed enrolling patients with recurrent sinonasal polyposis after endoscopic sinus surgery. All patients had development of symptomatic polyp disease despite aggressive postoperative topical steroid treatment. The study treatment entailed endoscopic placement of 4 mL of CMC foam hydrated with triamcinolone, 40 mg/mL (Kenalog 40; Bristol-Myers Squibb, New York, NY), into the ethmoid cavities bilaterally. Patients were evaluated using videoendoscopy and the Sino-Nasal Outcomes Test 20 (SNOT-20) at three time points: immediately before treatment, 7-14 days after treatment, and 28-35 days after treatment. The videoendoscopies were randomized and scored in a blinded fashion using a modification of the perioperative sinus endoscopy (POSE) scoring system.

RESULTS

Ten treatments were performed in eight patients; two patients underwent two treatments each. Mean SNOT-20 score improved at both 1 week and 1 month after treatment (2.44 versus 1.65, p < 0.05, and 2.44 versus 1.36, p < 0.01, respectively). Videoendoscopy also revealed improvement when evaluated with the modified POSE score at 1 week (11.8 versus 8.2, p < 0.001), and 1 month (11.8 versus 7.9, p < 0.001).

CONCLUSION

Endoscopic placement of steroid-infused CMC foam improves symptoms and endoscopic findings in patients with recurrent sinonasal polyposis after endoscopic sinus surgery.

A pathway-based approach to find novel markers of local glucocorticoid treatment in intermittent allergic rhinitis

BACKGROUND

Glucocorticoids (GCs) may affect the expression of hundreds of genes in different cells and tissues from patients with intermittent allergic rhinitis (IAR). It is a formidable challenge to understand these complex changes by studying individual genes. In this study, we aimed to identify (i) pathways affected by local GC treatment and (ii) examine if those pathways could be used to find novel markers of local GC treatment in nasal fluids from patients with IAR.

METHODS

Gene expression microarray- and iTRAQ-based proteomic analyses of nasal fluids, nasal fluid cells and nasal mucosa from patients with IAR were performed to find pathways enriched for differentially expressed genes and proteins. Proteins representing those pathways were analyzed with ELISA in an independent material of nasal fluids from 23 patients with IAR before and after treatment with a local GC.

RESULTS

Transcriptomal and proteomic high-throughput analyses of nasal fluids, nasal fluid cells and nasal mucosal showed that local GC treatment affected a wide variety of pathways in IAR such as the glucocorticoid receptor pathway and the acute phase response pathway. Extracellular proteins encoded by genes in those pathways were analyzed in an independent material of nasal fluids from patients. Proteins that changed significantly in expression included known biomarkers such as eosinophil cationic protein but also proteins that had not been previously described in IAR, namely CCL2, M-CSF, CXCL6 and apoH.

CONCLUSION

Pathway-based analyses of genomic and proteomic high-throughput data can be used as a complementary approach to identify novel potential markers of GC treatment in IAR.