CD4+ and CD8+ CD28^null T Cells Are Cytotoxic to Autologous Muscle Cells in Patients With Polymyositis

Abstract

Myotoxicity of CD4+ and CD8+ CD28(null) T cells is mediated by directed perforin-dependent killing and can be further influenced by IFNγ-induced HLA expression on muscle cells. The data suggest that CD28(null) T cells are key effector cells that contribute to the muscle cell damage in polymyositis.