ArticlePloS one2015
Surfactant Protein A in Exhaled Endogenous Particles Is Decreased in Chronic Obstructive Pulmonary Disease (COPD) Patients: A Pilot Study.
Article in PloS one, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 27 papers.
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Who cites it
27 citing papers in PubMed, 48 citations in OpenAlex.
- Airway and systemic biomarkers of health effects after short-term exposure to indoor ultrafine particles from cooking and candles - A randomized controlled double-blind crossover study among mild asthmatic subjects.Particle and fibre toxicology · 2023Trial
- Beyond spirometry: understanding COPD origins to support a new diagnostic approach.ERJ open research · 2026Review
- Determinants of respiratory tract aerosol generation in a diverse clinical population: an observational study.BMJ open respiratory research · 2025Observational
- Promoting immune defensive responses of epithelial cells in airway disease.Frontiers in allergy · 2025Review
- Particles in Exhaled Air (PExA): Clinical Uses and Future Implications.Diagnostics (Basel, Switzerland) · 2024Review
- Releasing high positive end-expiratory pressure to a low level generates a pronounced increase in particle flow from the airways.Intensive care medicine experimental · 2023Article
- New insight: particle flow rate from the airways as an indicator of cardiac failure in the intensive care unit.ESC heart failure · 2023Article
- An explorative study on respiratory health among operators working in polymer additive manufacturing.Frontiers in public health · 2023Article
- Aerosol measurement identifies SARS-CoV 2 PCR positive adults compared with healthy controls.Environmental research · 2023Observational
- Revisiting the role of pulmonary surfactant in chronic inflammatory lung diseases and environmental exposure.European respiratory review : an official journal of the European Respiratory Society · 2021Review
- Smoking induces sex-specific changes in the small airway proteome.Respiratory research · 2021Article
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- Mechanically ventilated patients exhibit decreased particle flow in exhaled breath as compared to normal breathing patients.ERJ open research · 2020Article
- Intra-individual variation of particles in exhaled air and of the contents of Surfactant protein A and albumin.PloS one · 2020Article
- Assessing small airways dysfunction in asthma, asthma remission and healthy controls using particles in exhaled air.ERJ open research · 2019Article
- Surfactant Protein A in particles in exhaled air (PExA), bronchial lavage and bronchial wash - a methodological comparison.Respiratory research · 2019Article
- Exhaled particles and small airways.Respiratory research · 2019Review
- Exhaled Breath Condensate in Childhood Asthma: A Review and Current Perspective.Frontiers in pediatrics · 2019Review
- A Three-Dimensional Human Tissue-Engineered Lung Model to Study Influenza A Infection.Tissue engineering. Part A · 2018Article
Corrections and comments
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Authors and funding
8 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundExhaled, endogenous particles are formed from the epithelial lining fluid in small airways, where surfactant protein A (SP-A) plays an important role in pulmonary host defense. Based on the knowledge that chronic obstructive pulmonary disease (COPD) starts in the small airway epithelium, we hypothesized that chronic inflammation modulates peripheral exhaled particle SP-A and albumin levels. The main objective of this explorative study was to compare the SP-A and albumin contents in exhaled particles from patients with COPD and healthy subjects and to determine exhaled particle number concentrations.
methodsPatients with stable COPD ranging from moderate to very severe (n = 13), and healthy non-smoking subjects (n = 12) were studied. Subjects performed repeated breath maneuvers allowing for airway closure and re-opening, and exhaled particles were optically counted and collected on a membrane using the novel PExA® instrument setup. Immunoassays were used to quantify SP-A and albumin.
resultsCOPD patients exhibited significantly lower SP-A mass content of the exhaled particles (2.7 vs. 3.9 weight percent, p = 0.036) and lower particle number concentration (p<0.0001) than healthy subjects. Albumin mass contents were similar for both groups.
conclusionsDecreased levels of SP-A may lead to impaired host defense functions of surfactant in the airways, contributing to increased susceptibility to COPD exacerbations. SP-A in exhaled particles from small airways may represent a promising non-invasive biomarker of disease in COPD patients.
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