Animal models in myositis

Purpose of review The etiology of the idiopathic inflammatory myopathies remains elusive. Delineation of pathogenic mechanisms in humans is hindered by the heterogeneity of different patient populations as well as the complexity and chronicity of the disease. Therefore, appropriate animal models are required to help clarify the immunopathogenesis of these disorders and to explore promising new therapies. The purpose of this review is to discuss recently published animal models in myositis, with a particular focus on idiopathic inflammatory myopathy. Recent finding Over the last few years, there has been considerable progress in the development of animal models for polymyositis and inclusion body myositis, but reports focusing on dermatomyositis have been limited. Although some of these systems are entirely novel, others have elucidated pathogenic mechanisms of existing models. Summary Several new animal models of myositis have emerged over the last few years that have revealed new inights regarding the pathophysiology of idiopathic inflammatory myopathy and that should set the foundation for development of new, more effective therapies against this often intractable disease.