Interferons as components of the complex web of reactions sustaining inflammation in idiopathic inflammatory myopathies.

Evidence accumulates implicating interferons (IFNs) in the chronic inflammation associated with the idiopathic inflammatory mypathies (IM). Dermatomyositis in particular appears to display a strong IFN type 1 signature. Proposed pathogenic actions of IFNs include the upregulation of major histocompatibility complex class I on muscle fibres, and the induction of a plethora of pro-inflammatory factors, including cytokines and chemokines. This review brings together findings on IFNs and IFN-induced factors, sketching their roles in IM immunopathogenesis in general and dermatomyositis in particular, and offering a basis for exploring their potential therapeutic relevance.