Sputum processing by mechanical dissociation: A rapid alternative to traditional sputum assessment approaches.
asthma
chronic obstructive pulmonary disease
eosinophil
inflammometry
neutrophil
severe asthma
sputum
Journal
The clinical respiratory journal
ISSN: 1752-699X
Titre abrégé: Clin Respir J
Pays: England
ID NLM: 101315570
Informations de publication
Date de publication:
Jul 2021
Jul 2021
Historique:
revised:
12
03
2021
received:
05
11
2020
accepted:
17
03
2021
pubmed:
23
3
2021
medline:
19
8
2021
entrez:
22
3
2021
Statut:
ppublish
Résumé
Sputum cytology is currently the gold standard to evaluate cellular inflammation in the airways and phenotyping patients with airways diseases. Sputum eosinophil proportions have been used to guide treatment for moderate to severe asthma. Furthermore, raised sputum neutrophils are associated with poor disease control and impaired lung function in both asthma and COPD and small airways disease in cystic fibrosis. However, induced-sputum analysis is subjective and resource heavy, requiring dedicated specialist processing and assessment; this limits its utility in most clinical settings. Indirect blood eosinophil measures have been adopted in clinical care. However, there are currently no good peripheral blood biomarkers of airway neutrophils. A resource-light sputum processing approach could thus help integrate induced sputum more readily into routine clinical care. New mechanical disruption (MD) methods can rapidly obtain viable single cell suspensions from sputum samples. The aim of this study was to compare MD sputum processing to traditional methods for cell viability, granulocyte proportions and sputum cytokine analysis. Sputum plugs were split and processed using traditional methods and the MD method, and samples were then compared. The MD method produced a homogeneous cell suspension in 62 s; 70 min faster than the standard method used. No significant difference was seen between the cell viability (p = 0.09), or the concentration of eosinophils (p = 0.83), neutrophils (p = 0.99) or interleukin-8 (p = 0.86) using MD. This cost-effective method of sputum processing could provide a more pragmatic, sustainable means of directly monitoring the airway milieu. Therefore, we recommend this method be taken forward for further investigation.
Sections du résumé
BACKGROUND
BACKGROUND
Sputum cytology is currently the gold standard to evaluate cellular inflammation in the airways and phenotyping patients with airways diseases. Sputum eosinophil proportions have been used to guide treatment for moderate to severe asthma. Furthermore, raised sputum neutrophils are associated with poor disease control and impaired lung function in both asthma and COPD and small airways disease in cystic fibrosis. However, induced-sputum analysis is subjective and resource heavy, requiring dedicated specialist processing and assessment; this limits its utility in most clinical settings. Indirect blood eosinophil measures have been adopted in clinical care. However, there are currently no good peripheral blood biomarkers of airway neutrophils. A resource-light sputum processing approach could thus help integrate induced sputum more readily into routine clinical care. New mechanical disruption (MD) methods can rapidly obtain viable single cell suspensions from sputum samples.
AIMS
OBJECTIVE
The aim of this study was to compare MD sputum processing to traditional methods for cell viability, granulocyte proportions and sputum cytokine analysis.
METHODS
METHODS
Sputum plugs were split and processed using traditional methods and the MD method, and samples were then compared.
RESULTS
RESULTS
The MD method produced a homogeneous cell suspension in 62 s; 70 min faster than the standard method used. No significant difference was seen between the cell viability (p = 0.09), or the concentration of eosinophils (p = 0.83), neutrophils (p = 0.99) or interleukin-8 (p = 0.86) using MD.
CONCLUSION
CONCLUSIONS
This cost-effective method of sputum processing could provide a more pragmatic, sustainable means of directly monitoring the airway milieu. Therefore, we recommend this method be taken forward for further investigation.
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
800-807Informations de copyright
© 2021 The Authors. The Clinical Respiratory Journal published by John Wiley & Sons Ltd.
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