French researchers have investigated the biological mechanisms involved in dermatomyositis (DM) by comparing muscle stem cells from patients and healthy subjects. They were particularly interested in the proliferative capacities of these cells and the levels of interferons, the signalling proteins involved in the immune response. The results of this work show that :
- the stem cells of patients have a much lower proliferation capacity than that observed in controls;
- this is evidenced by the accumulation of senescent cells, positively labelled with galactosidase, and could be explained by an abnormally high level of type I interferon;
