Carbon in airway macrophages from children with asthma.
Thorax
; 69(7): 654-9, 2014 Jul.
Article
in En
| MEDLINE
| ID: mdl-24567296
ABSTRACT
BACKGROUND:
Airway macrophage (AM) phagocytosis is impaired in severe asthma. Prostaglandin (PG) E2 and D2 are increased in severe asthma and suppress AM phagocytic function in vitro. In this study, we sought evidence for PG-mediated impairment of phagocytosis of inhalable carbonaceous particulate matter (PM) by AM in children with severe asthma compared with mild asthmatics and healthy controls.METHODS:
AM were obtained from children with asthma and healthy controls using induced sputum. AM carbon area (µm(2)) was assessed by image analysis. In a subgroup of asthmatics, urinary PGE2 and PGD2 metabolites were measured by high-performance liquid chromatography, and PM exposure at the home address was modelled. Phagocytosis of PM by human monocyte-derived macrophages and rat AM was assessed in vitro by image analysis.RESULTS:
AM carbon was 51% lower in children with moderate-to-severe asthma (n=36) compared with mild asthmatics (n=12, p<0.01) and healthy controls (n=47, p<0.01). There was no association between modelled PM exposure and AM carbon in 33 asthmatics who had a urine sample, but there was an inverse association between AM carbon and urinary metabolites of PGE2 and D2 (n=33, rs=-0.40, p<0.05, and rs=-0.44, p<0.01). PGE2 10(-6) M, but not PGD2 10(-6) M, suppressed phagocytosis of PM10 by human macrophages in vitro (p<0.05 vs control). PGE2 10(-6) M also suppressed phagocytosis of PM10 by rat AM in vitro (p<0.01 vs control).CONCLUSIONS:
Phagocytosis of inhaled carbonaceous PM by AMs is impaired in severe asthma. PGE2 may contribute to impaired AM phagocytic function in severe asthma.Key words
Full text:
1
Collection:
01-internacional
Health context:
2_ODS3
Database:
MEDLINE
Main subject:
Phagocytosis
/
Asthma
/
Sputum
/
Carbon
/
Environmental Exposure
/
Macrophages
Type of study:
Observational_studies
/
Risk_factors_studies
Limits:
Child
/
Female
/
Humans
/
Male
Country/Region as subject:
Europa
Language:
En
Journal:
Thorax
Year:
2014
Document type:
Article