New insights into how asthma pathways could be blocked revealed

Researchers have discovered new insights into how asthma may be caused, by identifying three distinct groups of asthma patients characterised by the activity of different genes in an individual’s airways.

In the study, which is published in the journal Science Translational Medicine, researchers led by Professor Peter Bradding (pictured) from the Department of Infection, Immunity and Inflammation looked prospectively at lung samples from 51 asthma patients who had a range of disease severity and identified three different clusters in the airways called Th2-high, Th17-high, and Th2/17-low.

Patients exhibited either high Th2 or high Th17 activity, or low activity of both pathways. Interestingly, no patients had simultaneously high Th2 and Th17 activity, indicating that these pathways are somehow mutually exclusive.

The research team at NIAID in the USA found in a mouse model of asthma that when Th2-activity was inhibited this promoted Th17 activity. When Th2 and Th17 were simultaneously blocked in the mouse model of asthma, the researchers observed greater benefit than blocking one pathway alone, suggesting that new therapies targeting both pathways may demonstrate better efficacy than targeting either pathway alone.

Professor Bradding said: “This research gives new insight into the molecular mechanisms that drive asthma. Because new treatments that block Th2 pathways may promote Th17 pathways, it may be more effective to block both at the same time, rather than either alone. This can be tested in future research trials in patients.”