The response of macrophages to Moraxella catarrhalis infection
The response of macrophages to Moraxella catarrhalis infection
Infection by certain bacterial species can predispose an individual to developing asthma and trigger asthmatic exacerbations. Moraxella catarrhalis is one such organism, yet there is little data on the innate immune responses to this pathogen. Alveolar macrophages are the predominant immune cell isolated from the airway and show phenotypic differences in health and asthma. Macrophages are crucial in the immune response by pathogen recognition receptor (PRR)mediated detection of organisms, release of pro-inflammatory mediators and presentation of antigens to other cells of the immune system to link the innate and adaptive immune response. The aim of this work was to investigate the response of macrophages to M.catarrhalis. Monocyte-derived macrophages (MDM) were exposed to M.catarrhalis for 2h, incubated with antiobiotics for 22h before analysis at 24h. The expression of PRRs were analysed by real time PCR. A significant increase of retinoic acid-inducible gene(RIG)I expression(p<0.0001) was found; however, IFN-β was not detected. Conversely, expression of toll-like receptor (TLR)4 decreased(p=0.0003). Despite this, the release of IL-1β and IL-8 was detected in a dose-dependent manner by ELISA(p<0.0001). The surface expression of antigen presentation molecules were analysed by flow cytometry and showed an upregulation of major histocompatibility complex (MHC)-II(p=0.002) and MR1(p=0.0015), but only a slight upregulation of MHC-I(p=0.0728). This work suggests that MDM respond to M.catarrhalis and act to induce further immune cell effector actions. Understanding the MDM response to M.catarrhalis will allow for future comparisons to determine differences between the phenotypically distinctive macrophages in health and asthma.
Ackland, Jodie
dba59510-7535-47f8-b2ba-2d49dfa7fbd8
Wallington, Joshua
bbbcfb18-8d5c-4ce3-9917-a963baedf422
Cleary, David
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Christodoulides, Myron
eba99148-620c-452a-a334-c1a52ba94078
Staples, Karl
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1 September 2017
Ackland, Jodie
dba59510-7535-47f8-b2ba-2d49dfa7fbd8
Wallington, Joshua
bbbcfb18-8d5c-4ce3-9917-a963baedf422
Cleary, David
f4079c6d-d54b-4108-b346-b0069035bec0
Christodoulides, Myron
eba99148-620c-452a-a334-c1a52ba94078
Staples, Karl
e0e9d80f-0aed-435f-bd75-0c8818491fee
Ackland, Jodie, Wallington, Joshua, Cleary, David, Christodoulides, Myron and Staples, Karl
(2017)
The response of macrophages to Moraxella catarrhalis infection.
European Respiratory Journal, 50 (Suppl 61), [PA4127].
(doi:10.1183/1393003.congress-2017.PA4127).
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Meeting abstract
Abstract
Infection by certain bacterial species can predispose an individual to developing asthma and trigger asthmatic exacerbations. Moraxella catarrhalis is one such organism, yet there is little data on the innate immune responses to this pathogen. Alveolar macrophages are the predominant immune cell isolated from the airway and show phenotypic differences in health and asthma. Macrophages are crucial in the immune response by pathogen recognition receptor (PRR)mediated detection of organisms, release of pro-inflammatory mediators and presentation of antigens to other cells of the immune system to link the innate and adaptive immune response. The aim of this work was to investigate the response of macrophages to M.catarrhalis. Monocyte-derived macrophages (MDM) were exposed to M.catarrhalis for 2h, incubated with antiobiotics for 22h before analysis at 24h. The expression of PRRs were analysed by real time PCR. A significant increase of retinoic acid-inducible gene(RIG)I expression(p<0.0001) was found; however, IFN-β was not detected. Conversely, expression of toll-like receptor (TLR)4 decreased(p=0.0003). Despite this, the release of IL-1β and IL-8 was detected in a dose-dependent manner by ELISA(p<0.0001). The surface expression of antigen presentation molecules were analysed by flow cytometry and showed an upregulation of major histocompatibility complex (MHC)-II(p=0.002) and MR1(p=0.0015), but only a slight upregulation of MHC-I(p=0.0728). This work suggests that MDM respond to M.catarrhalis and act to induce further immune cell effector actions. Understanding the MDM response to M.catarrhalis will allow for future comparisons to determine differences between the phenotypically distinctive macrophages in health and asthma.
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Published date: 1 September 2017
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Local EPrints ID: 441596
URI: http://eprints.soton.ac.uk/id/eprint/441596
ISSN: 0903-1936
PURE UUID: 5f848a1f-b1fb-4ab9-b39a-7c941d9cb54f
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Date deposited: 19 Jun 2020 16:30
Last modified: 21 Nov 2024 03:01
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Author:
Joshua Wallington
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