A new Australian study may help to explain why asthmatics have trouble suppressing the inflammation triggered by respiratory virus infections. And it’s to do with Rhinovirus C.
In particular, the inflammation due to members of one species of rhinovirus (RV), the RV-Cs, considered the worst of the “common cold” viruses for causing exacerbations or “asthma attacks”, in children with asthma.
The study found that fewer regulatory T cells (Tregs) from asthmatic children responded to an RV-C stimulus than to an RV-A stimulus, compared to healthy control children.
Tregs are a small proportion of circulating T cells, but, as the name suggests, they play a (very important) role in modifying the immune response to prevent it over-reacting to an insult like a virus infection.
- the study mimicked RV infection by stimulating blood cells collected from asthmatic and control children, using tiny bits of very “immune exciting” (immunodominant) protein in the laboratory
The study also found that there was no difference between the asthmatic and healthy children’s immune system when it came to remembering past infection, but that asthmatic children tended to have lower overall numbers of Treg compared to healthy control children stimulation to RVs.
A double punch from the RV-Cs for those susceptible to chronic wheeze and another piece added to the asthma puzzle.
- T-cell responses against rhinovirus species A and C in asthmatic and healthy children