Carbon in airway macrophages from children with asthma
New research undertaken jointly between King's and the Centre for Paediatrics at Queen Mary, University of London is featured on the cover of this month's edition of Thorax, one of the world's leading respiratory medicine journals.
The investigators looked at the amount of black carbon that could be measured in immune cells in the airways of children. These cells, called macrophages, are responsible for removing inhaled particles from the lung lining. In healthy children, more black carbon in these cells, linked to greater exposure to air pollution, has been associated with impaired lung growth (Kulkarni NEJM 2006).
In this latest study, cells from healthy children taking part in the EXHALE Low Emission Zone study were compared to cells from children with asthma taken from paediatric hospitals in London. The samples were then matched to air pollution exposures calculated by the team at Kings.
The results showed that black carbon levels were roughly halved in the cells from children with more severe asthma - despite them breathing in the same amount of air pollution. Dr Rossa Brugha, who led the research, explains:
‘We have known for a while that, in children with asthma, these macrophages may not function as well as they do in healthy children. This study shows that the immune system in children with asthma can't deal with these inhaled particles - instead of clearing them away, we assume that these particles remain in the lungs for longer, causing the lining of the lungs to become inflamed. This may contribute to why children with asthma get more severe symptoms when air quality is poor.’
Dr Brugha now advises children in the asthma clinic at the Royal London to use the London Air app to check air quality levels before doing sport outdoors.
Read the full paper in the journal Thorax.