Search Results (18)

Background: Functional endoscopic sinus surgery (FESS) is the treatment of choice for medically refractory CRS. However, the success rate of FESS is dependent on both baseline medical and demographic characteristics. Consequently, we performed an analysis of systemic/nasal cytokines and the sinus microbiome to assess their impact on the SNOT-22 response after functional endoscopic sinus surgery (FESS). Methods: A prospective observational study was performed on 44 patients with chronic rhinosinusitis undergoing FESS between December 2021 and September 2022. Diseased sinus tissue from 25 patients was subjected to whole-exome sequencing (WES) for taxonomical profiling of the sinus bacterial composition. Additional data collection included demographics, comorbidities, baseline sinonasal outcome test scores, post-operative sinonasal outcome test scores (at 3–4 months), and nasal/systemic cytokines. Results: Our analysis demonstrated that CRSwNP patients in the surgical responder cohort had statistically significantly higher median [P25, P75] levels of intra-nasal IL-5, indicating type 2 sinonasal disease (63 pg/μL [28, 118] versus 17 pg/μL [16.6, 18], p = 0.04). At the genus level, the relative abundance of Staphylococcus was significantly higher in the surgical non-responder cohort compared to the responder group. An ROC curve was highly accurate at distinguishing responders versus non-responders to FESS based on a microbiota-based random forest model (AUC = 0.92). Conclusions: Intra-nasal IL-5 levels and the bacterial composition of the sinus microbiome may be important predictors of symptomatic response after sinus surgery. Full article

Traffic-related air pollution (TRAP) remains a concern for public health. However, the exact mechanisms through which TRAP affects the respiratory system are still not fully understood. This study aimed to investigate the nasal microbiome change in healthy adults after short-term exposure to TRAP, contributing to the understanding of the adverse health effects associated with TRAP. A randomized crossover controlled trial was conducted from 9 March to 30 March 2024 among college students aged 19–24 years. Twenty healthy students were recruited through a baseline questionnaire survey and randomly assigned into two groups. One group followed a crowed-testing procedure: the park portion, a three-week washout period, and then the road portion, while the other group experienced the opposite procedure. Both groups were fully exposed to either a park environment or a road environment with high traffic volume. Nasal mucus samples were collected from the participants at the end of the trial, and then 16SrRNA sequencing was performed to analyze the differences in compositional structure and diversity of the nasal microbiome when volunteers were exposed to different levels of TRAP. The α-diversity indices, including the Chao1 index (p = 0.0097), observed species index (p = 0.0089), and Faith’s PD index (p = 0.0255), demonstrated a significant increase in the nasal microbiome of healthy adults following short-term exposure to TRAP. Visualization through a two-dimensional NMDS plot (stress value < 0.2) indicated that nasal bacterial species distribution became richer after TRAP exposure. Furthermore, the relative abundance of nasal Firmicutes (Bacillota), Bacteroidota, and Actinobacteriota phyla, especially Firmicutes phylum, exhibited a richer distribution after conducting the trial in the road environment with high levels of TRAP, which was shown in the significance test of signature species. Collectively, our study indicates that short-term exposure to TRAP can affect the composition of the nasal microbiota in healthy adults. These findings offer a scientific basis for understanding how TRAP causes respiratory diseases. Full article

The human respiratory tract is colonized by a complex microbial community that helps maintain respiratory health and plays a crucial role in defending the host from infections. Respiratory viruses have been demonstrated to alter microbiota composition, resulting in opportunistic species expansion, and increasing the disease severity and host susceptibility to bacterial co-infections. This study aims to examine the compositional differences in the nasal microbiota between SARS-CoV-2-infected and non-infected patients. We conducted Oxford Nanopore full-length 16S rRNA sequencing on nasal swabs from 94 COVID-19 negative and 85 COVID-19 positive patients collected during the SARS-CoV-2 pandemic in Malta. Our analysis identified significant alpha and beta diversity differences in the nasal microbiota composition among our study groups. We observed a trend toward decreased microbial richness and evenness in the COVID-Positive cohort with and increased abundance of common nasal opportunistic species including Citrobacter koseri, Dolosigranulum pigrum, Haemophilus influenzae, Klebsiella pneumoniae, and Moraxella catarrhalis. The findings from this study are in line with previously published papers identifying key alterations in the nasal microbiota composition associated with SARS-CoV-2 infection. Understanding these microbiome-driven mechanisms could present novel prognostic markers or offer new approaches for disease prevention and treatment. Full article

Background: Susceptibility to and severity of pulmonary infections increase with ethanol consumption. We have previously shown that ethanol-induced changes in the gut microbiome disrupt gut homeostasis, allowing for the translocation of proinflammatory mediators into the circulation and eliciting an immune response in the lung. Additionally, targeting the gut with butyrate supplementation not only rescues ethanol-induced disruptions to gut health but also reverses aspects of immune dysregulation in the lungs. Here, we assessed the impact of this connection on a subsequent infectious challenge. Methods: To assess if ethanol-induced alterations to the gut microbiome could also impact the host response to a pulmonary infectious challenge, we employed a chronic-binge ethanol-feeding mouse model followed by a nasal instillation of Pseudomonas aeruginosa. Results: In addition to altering gut microbiome composition and metabolism, ethanol consumption also disrupted the local immune response as demonstrated by suppressed cecal SIgA levels, a decreased presence of CD3⁺CD8a⁺ cytotoxic T cells in the proximal colon mucosa, and depleted CD3⁺CD8a⁺ T cells and CD11c⁺CD8a⁺ dendritic cells in the mesenteric lymph nodes. Circulatory Ly6G⁺CD11b⁺ neutrophils increased, indicating a systemic change in immune-cell presence with ethanol exposure. Ethanol exposure increased CD11c⁺CD64⁺ macrophages and Ly6G⁺CD11b⁺ neutrophils in the lungs, with neutrophil populations being further exacerbated during a bacterial challenge with Pseudomonas aeruginosa. Lipocalin 2, a marker of oxidative stress, was also elevated with ethanol consumption, though not with infection. Conclusions: These data suggest that ethanol-induced changes in the gut microbiome and immune environment are linked to dysfunctional immune responses in the intestine, blood, and the lungs, compromising the pulmonary immune response during an infectious challenge in mice. Full article

Parkinson’s disease (PD) is characterized by the progressive degeneration of dopaminergic neurons, leading to a range of motor and non-motor symptoms. Background/Objectives: Over the past decade, studies have identified a potential link between the microbiome and PD pathophysiology. The literature suggests that specific bacterial communities from the gut, oral, and nasal microbiota may be involved in neuroinflammatory processes, which are hallmarks of PD. This review aims to comprehensively analyze the current research on the composition, diversity, and dysbiosis characteristics of the nasal and oral microbiota in PD. Methods: Through a comprehensive search across scientific databases, we identify twenty original studies investigating the nasal and oral microbiota in PD. Results: Most of these studies demonstrate the substantial roles of bacterial communities in neuroinflammatory pathways associated with PD progression. They also underscore the influences of microbiota-derived factors on key aspects of PD pathology, including alpha-synuclein aggregation and immune dysregulation. Conclusions: Finally, we discuss the potential diagnostic and therapeutic implications of modulating the nasal and oral microbiota in PD management. This analysis seeks to identify potential avenues for future research in order to clarify the complex relationships between these microorganisms and PD. Full article

This study aimed to determine shifts in microbial populations regarding richness and diversity from the daily use of a popular over-the-counter nasal spray. In addition, the finding of nasal commensal bacterial species that overlap with the oral microbiome may prove to be potential probiotics for the “gateway microbiomes”. Nasal swab samples were obtained before and after using the most popular over-the-counter (OTC) nasal spray in 10 participants aged 18–48. All participants were healthy volunteers with no significant medical histories. The participants were randomly assigned a number by randomizing software and consisted of five men and five women. The sampling consisted of placing a nasal swab atraumatically into the nasal cavity. The samples were preserved and sent to Northwestern University Sequencing Center for whole-genome deep sequencing. After 21 days of OTC nasal spray use twice daily, the participants returned for further nasal microbiome sampling. The microbial analysis included all bacteria, archaea, viruses, molds, and yeasts via deep sequencing for species analysis. The Northwestern University Sequencing Center utilized artificial intelligence analysis to determine shifts in species and strains following nasal spray use that resulted in changes in diversity and richness. Full article

Chronic rhinosinusitis (CRS) is a multifactorial infection of the nasal cavity and sinuses. In this study, nasal swabs from control donors (N = 128) and patients with CRS (N = 246) were analysed. Culture methods and metagenomics revealed no obvious differences in the composition of the bacterial communities between the two groups. However, at the functional level, several metabolic pathways were significantly enriched in the CRS group compared to the control group. Pathways such as carbohydrate transport metabolism, ATP synthesis, cofactors and vitamins, photosynthesis and transcription were highly enriched in CRS. In contrast, pathways related to lipid metabolism were more representative in the control microbiome. As S. aureus is one of the main species found in the nasal cavity, staphylococcal isolates from control and CRS samples were analysed by microarray and functional assays. Although no significant genetic differences were detected by microarray, S. aureus from CRS induced less cytotoxicity to lung cells and lower rates of glycolysis in host cells than control isolates. These results suggest the differential modulation of staphylococcal virulence by the environment created by other microorganisms and their interactions with host cells in control and CRS samples. These changes were reflected in the differential expression of cytokines and in the expression of Agr, the most important quorum-sensing regulator of virulence in S. aureus. In addition, the CRS isolates remained stable in their cytotoxicity, whereas the cytotoxic activity of S. aureus isolated from control subjects decreased over time during in vitro passage. These results suggest that host factors influence the virulence of S. aureus and promote its adaptation to the nasal environment during CRS. Full article

(1) Background: The COVID-19 pandemic left many intriguing mysteries. Retrospective vulnerability trends tie as strongly to odd demographics as to exposure profiles, genetics, health, or prior medical history. This article documents the importance of nasal microbiome profiles in distinguishing infection rate trends among differentially affected subgroups. (2) Hypothesis: From a detailed literature survey, microbiome profiling experiments, bioinformatics, and molecular simulations, we propose that specific commensal bacterial species in the Pseudomonadales genus confer protection against SARS-CoV-2 infections by expressing proteases that may interfere with the proteolytic priming of the Spike protein. (3) Evidence: Various reports have found elevated Moraxella fractions in the nasal microbiomes of subpopulations with higher resistance to COVID-19 (e.g., adolescents, COVID-19-resistant children, people with strong dietary diversity, and omnivorous canines) and less abundant ones in vulnerable subsets (the elderly, people with narrower diets, carnivorous cats and foxes), along with bioinformatic evidence that Moraxella bacteria express proteases with notable homology to human TMPRSS2. Simulations suggest that these proteases may proteolyze the SARS-CoV-2 spike protein in a manner that interferes with TMPRSS2 priming. Full article

Background: Antibiotic eye drops are frequently used in clinical practice. Due to the anatomical connection via the nasolacrimal duct, it seems possible that they have an influence on the nasal/pharyngeal microbiome. This was investigated by using two different commonly used antibiotic eye drops. Methods: 20 subjects were randomized to four groups of five subjects receiving eye drops containing gentamicin, ciprofloxacin, or, as controls, unpreserved povidone or benzalkonium chloride-preserved povidone. Nasal and pharyngeal swabs were performed before and after the instillation period. Swabs were analyzed by Illumina next-generation sequencing (NGS)-based 16S rRNA analysis. Bacterial culture was performed on solid media, and bacterial isolates were identified to the species level by MALDI-TOF MS. Species-dependent antimicrobial susceptibility testing was performed using single isolates and pools of isolates. Results: Bacterial richness in the nose increased numerically from 163 ± 30 to 243 ± 100 OTUs (gentamicin) and from 114 ± 17 to 144 ± 45 OTUs (ciprofloxacin). Phylogenetic diversity index (pd) of different bacterial strains in the nasal microbiome increased from 12.4 ± 1.0 to 16.9 ± 5.6 pd (gentamicin) and from 10.2 ± 1.4 to 11.8 ± 3.1 pd (ciprofloxacin). Unpreserved povidone eye drops resulted in minimal changes in bacterial counts. Preservative-containing povidone eye drops resulted in no change. A minor increase (1–2-fold) in the minimal inhibitory concentration (MIC) was observed in single streptococcal isolates. Conclusions: Antibiotic eye drops could affect the nasal microbiome. After an instillation period of seven days, an increase in the diversity and richness of bacterial strains in the nasal microbiome was observed. Full article

SARS-CoV-2, one of the human RNA viruses, is widely studied around the world. Significant efforts have been made to understand its molecular mechanisms of action and how it interacts with epithelial cells and the human microbiome since it has also been observed in gut microbiome bacteria. Many studies emphasize the importance of surface immunity and also that the mucosal system is critical in the interaction of the pathogen with the cells of the oral, nasal, pharyngeal, and intestinal epithelium. Recent studies have shown how bacteria in the human gut microbiome produce toxins capable of altering the classical mechanisms of interaction of viruses with surface cells. This paper presents a simple approach to highlight the initial behavior of a novel pathogen, SARS-CoV-2, on the human microbiome. The immunofluorescence microscopy technique can be combined with spectral counting performed at mass spectrometry of viral peptides in bacterial cultures, along with identification of the presence of D-amino acids within viral peptides in bacterial cultures and in patients’ blood. This approach makes it possible to establish the possible expression or increase of viral RNA viruses in general and SARS-CoV-2, as discussed in this study, and to determine whether or not the microbiome is involved in the pathogenetic mechanisms of the viruses. This novel combined approach can provide information more rapidly, avoiding the biases of virological diagnosis and identifying whether a virus can interact with, bind to, and infect bacteria and epithelial cells. Understanding whether some viruses have bacteriophagic behavior allows vaccine therapies to be focused either toward certain toxins produced by bacteria in the microbiome or toward finding inert or symbiotic viral mutations with the human microbiome. This new knowledge opens a scenario on a possible future vaccine: the probiotics vaccine, engineered with the right resistance to viruses that attach to both the epithelium human surface and gut microbiome bacteria. Full article

Chronic rhinosinusitis (CRS) is a heterogenous disease that causes persistent paranasal sinus inflammation in children. Microorganisms are thought to contribute to the etiology and progression of CRS. Culture-independent microbiome analysis offers deeper insights into sinonasal microbial diversity and microbe–disease associations than culture-based methods. To date, CRS-related microbiome studies have mostly focused on the adult population, and only one study has characterized the pediatric CRS microbiome. In this study, we analyzed the bacterial diversity of adenoid tissue, adenoid swab, maxillary sinus, and sinus wash samples from 45 pediatric CRS patients recruited from the Johns Hopkins All Children’s Hospital (JHACH) in St. Petersburg, FL, USA. The alpha diversity in these samples was associated with baseline nasal steroid use, leukotriene receptor antagonist (LTRA) use, and total serum immunoglobulin (Ig) E (IgE) level. Streptococcus, Moraxella, and Haemophilus spp. were most frequently identified from sinus cultures and the sequenced 16S rRNA gene content. Comparative analyses combining our samples with the samples from the previous microbiome study revealed differentially abundant genera between patients with pediatric CRS and healthy controls, including Cutibacterium and Moraxella. Additionally, the abundances of Streptobacillus and Staphylococcus were consistently correlated with age in both adenoid- and sinus-derived samples. Our study uncovers new associations of alpha diversity with clinical parameters, as well as associations of specific genera with disease status and age, that can be further investigated. Full article

The human upper respiratory tract comprises the nasal cavity, pharynx and larynx regions and offers distinct microbial communities. However, an imbalance and alterations in the nasal mucosa microbiome enhance the risk of chronic respiratory conditions in patients with allergic respiratory diseases. This is particularly important in children and adolescents once allergic rhinitis (AR) is an inflammatory disorder of the nasal mucosa, often associated with an increase in pulmonary allergic inflammation. Therefore, this systematic review aimed to collect scientific data published concerning the microbial community alterations in nasal mucosa of children and adolescents suffering from AR or in association with adenotonsillar hypertrophy (AH) and allergic rhinoconjunctivitis (ARC). The current study was performed using the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Publications related to microbiome alterations in the nasal mucosa in pediatric age, studies including next-generation sequencing platforms, and studies exclusively written in the English language were some of the inclusion criteria. In total, five articles were included. Despite the scarcity of the published data in this research field and the lack of prospective studies, the genera Acinetobacter, Corynebacterium, Dolosigranulum, Haemophilus, Moraxella, Staphylococcus and Streptococcus dominate the nares and nasopharyngeal microbiome of the pediatric population regardless of their age. However, an imbalance in the resident bacterial community in the nasal mucosa was observed. The genera Acinetobacter, and Pseudomonas were more abundant in the nasal cavity of AR and AH children, while Streptococcus and Moraxella were predominant in the hypopharyngeal region of AR infants. An abundance of Staphylococcus spp. was also reported in the anterior nares and hypopharyngeal region of children and adolescents suffering from AR passive smoke exposure and ARC. These records suggest that different nasal structures, ageing, smoke exposure and the presence of other chronic disorders shape the nasal mucosa microbiome. Therefore, the establishment of adequate criteria for sampling would be established for a deeper understanding and a trustworthy comparison of the microbiome alterations in pediatric age. Full article

Airborne fungi are ubiquitous in the environment and are commonly associated with airway inflammatory diseases. The innate immune defense system eliminates most inhaled fungi. However, some influence the development of chronic rhinosinusitis. Fungal CRS is thought of as not a common disease, and its incidence increases over time. Fungi are present in CRS patients and in healthy sinonasal mucosa. Although the immunological mechanisms have not been entirely explained, CRS patients may exhibit different immune responses than healthy people against airborne fungi. Fungi can induce Th1 and Th2 immune responses. In CRS, Th2-related immune responses against fungi are associated with pattern recognition receptors in nasal epithelial cells, the production of inflammatory cytokines and chemokines from nasal epithelial cells, and interaction with innate type 2 cells, lymphocytes, and inflammatory cells. Fungi also interact with neutrophils and eosinophils and induce neutrophil extracellular traps (NETs) and eosinophil extracellular traps (EETs). NETs and EETs are associated with antifungal properties and aggravation of chronic inflammation in CRS by releasing intracellular granule proteins. Fungal and bacterial biofilms are commonly found in CRS and may support chronic and recalcitrant CRS infection. The fungal–bacterial interaction in the sinonasal mucosa could affect the survival and virulence of fungi and bacteria and host immune responses. The interaction between the mycobiome and microbiome may also influence the host immune response, impacting local inflammation and chronicity. Although the exact immunopathologic role of fungi in the pathogenesis of CRS is not completely understood, they contribute to the development of sinonasal inflammatory responses in CRS. Full article

Numerous studies have highlighted the role of the gastrointestinal system in Parkinson disease pathogenesis. It is likely triggered by proinflammatory markers produced by specific gut bacteria. This review’s aim is to identify gut bacterial biomarkers of Parkinson disease. A comprehensive search for original research papers on gut microbiota composition in Parkinson disease was conducted using the PubMed, Embase, and Scopus databases. Research papers on intestinal permeability, nasal and oral microbiomes, and interventional studies were excluded. The yielded results were categorized into four groups: Parkinson disease vs. healthy controls; disease severity; non-motor symptoms; and clinical phenotypes. This review was conducted in accordance with the PRISMA 2020 statement. A total of 51 studies met the eligibility criteria. In the Parkinson disease vs. healthy controls group, 22 bacteria were deemed potentially important. In the disease severity category, two bacteria were distinguished. In the non-motor symptoms and clinical phenotypes categories, no distinct pathogen was identified. The studies in this review report bacteria of varying taxonomic levels, which prevents the authors from reaching a clear conclusion. Future research should follow a unified methodology in order to identify potential biomarkers for Parkinson disease. Full article

Staphylococcus lugdunensis is an opportunistic pathogen found in the healthy human skin microbiome bacterial community that is able to cause infections of diverse localization, manifestation, and course, including laryngological infections, such as necrotizing sinusitis. Chronic maxillary sinusitis is a disease present in up to one third of European and American populations, and its etiology is not fully described. Within this study, we aimed to characterize 18 S. lugdunensis strains recovered from maxillary sinuses and evaluate them as etiological agents of chronic disease. We performed MLST analysis, the complex analysis of both phenotypic and genetic virulence factors, antibiotic susceptibility profiles, and biofilm formation assay for the detection of biofilm-associated genes. Altogether, S. lugdunensis strains were clustered into eight different STs, and we demonstrated several virulence factors associated with the chronic disease. All tested strains were able to produce biofilm in vitro with numerous strains with a very strong ability, and overall, they were mostly susceptible to antibiotics, although we found resistance to fosfomycin, erythromycin, and clindamycin in several strains. We believe that further in-depth analysis of S. lugdunensis strains from different niches, including the nasal one, should be performed in the future in order to reduce infection rate and broaden the knowledge about this opportunistic pathogen that is gaining attention. Full article