Exacerbation status is linked to dysfunctional phagocytosis in stable in Chronic Obstructive Pulmonary Disease (COPD) patients but not to pulmonary function

Journal Contribution ResearchOnline@JCU
Lee, K.;Lee, H.;Munns, S.;Rush, C.;Nolan, G.
Abstract

Introduction/Aim: Chronic obstructive pulmonary disease (COPD) is a significant and increasing public health challenge. Much of the disease burden and economic cost of COPD is associated with acute exacerbations and resulting bacterial colonisation of the airways. The aim of this study is to determine whether the bactericidal functions of phagocytic cells (monocytes and neutrophils) are impaired, predisposing COPD patients to increased bacterial infections. Method: Spirometry and venous blood were collected from COPD patients across the GOLD2015 spectrum and a group of healthy controls were recruited for comparison. Flow cytometry was used to determine differential counts for a range of leukocytes and internalisation of fluorescently labelled Streptococcus pneumoniae in whole blood phagocytes. Groups were compared by ANOVA and post hoc tests. Results: Results demonstrated that peripheral blood monocytes (p=0.04) and neutrophils (p=<0.0005) in exacerbation prone COPD patients had significant reductions in both bactericidal activity against S. pneumoniae (p=0.01) and internalisation of inert microparticles (p=0.01) compared to healthy controls and also stable COPD patients. Data collection remains ongoing. Conclusion: This study has demonstrated that defective phagocytosis in COPD patients prone to exacerbations is irrespective of disease severity (according to GOLD2015). Thus dysfunctional cellular activity of blood monocytes and neutrophils, and a failure to mount an appropriate immune response to infection, may enable bacteria to overwhelm host defences leading to further lung tissue damage.

Journal

Respirology

Publication Name

N/A

Volume

23

ISBN/ISSN

1440-1843

Edition

N/A

Issue

Suppl 1

Pages Count

1

Location

Brisbane

Publisher

Wiley-Blackwell

Publisher Url

N/A

Publisher Location

Respirology

Publish Date

N/A

Url

N/A

Date

N/A

EISSN

N/A

DOI

10.1111/resp.13268