Single cell RNA sequencing sheds light on infiltrating T cells in idiopathic inflammatory myopathies

Idiopathic inflammatory myopathies (IIM), also referred to as “myositis,” are a group of heterogeneous autoimmune disorders characterised by muscle weakness, atrophy and progressive reduced mobility (Lundberg et al, 2021). IIM represent a significant health burden in adult populations, affecting individuals at a mean age of 50 with an estimated prevalence of 2.9–34 per 100,000 (Dobloug et al, 2015; Svensson et al, 2017). IIM encompass several subtypes including dermatomyositis, immune‐mediated necrotising myopathy, inclusion‐body myositis, antisynthetase syndrome and polymyositis, which are characterised by specific clinical features, histopathological findings and autoantibody status (Pinal‐Fernandez et al, 2020).