They compared samples from those with the disease to samples from healthy volunteers. They measured a type of white blood cells called T-cells which are important for fighting infection but can end up over-reacting and cause inflammation in areas of the body, such as the skin leading to psoriasis or eczema.
In research published in The Journal of Allergy and Clinical Immunology, the team applied a technology called mass cytometry which allows for identification of the specific type of T-cell based on the proteins on their surface.
They found that there were several differences in several types of T-cells among the samples from those with the disease and healthy as well as between the two diseases both in relative abundance and in their ability to produce an immune response.
Our findings highlight that both psoriasis and eczema are not just diseases of the skin and that systemic immunity cells play an important role– Lead author of the study Dr Paola Di Meglio.
The team found that a type of cell called Recirculating memory T cells (TRcM) that had been in the skin and gut previously was more abundant in the blood of individuals with AD and produced a specific protein (IL-22) implicated in the inflammation and the causes underpinning AD. They identified that the more IL-22 produced by the TRcMs the more severe the disease was.
These findings support ongoing clinical trial that is aimed at blocking the production of IL-22 in AD.
“Our work paves the way to future studies aimed, for example, at assessing whether IL-22-producing TRcM may be useful as biomarkers of response to IL-22 blockade in AD.” adds Dr Di Meglio