Decreased expression of interleukin-1α, interleukin-1β, and cell adhesion molecules in muscle tissue following corticosteroid treatment in patients with polymyositis and dermatomyositis

Abstract

Changes in the muscle expression of key molecules in the inflammatory process, such as IL-1alpha and IL-1beta, ICAM-1 and class I MHC antigens, showed a consistent but not complete concordance with changes in and status of muscle function in patients with myositis who received the current standard treatment for the disease. These data indicate that it is possible to further evaluate various therapies for myositis using molecular analysis of muscle biopsy specimens obtained on repeated occasions. In addition, the data demonstrate a dissociation between muscle function and degree of inflammatory infiltration in the affected muscles and suggest that the functional defects are more related to the expression of molecules such as IL-1alpha in muscle capillaries than to the mere presence of inflammatory cells in the affected muscles.