Journal of Neuroimmunology, 2000, 111:1-2:146-151
August 2000;
Abstract
Recent studies have shown an up-regulation of the Fas/Fas ligand system in inflammatory myopathies. In myositis, however, the major Fas-mediated cytotoxicity which activates caspases bypasses apoptosis. We therefore evaluated the expression of proteins promoting cell survival, such as bcl-2, bcl-xl and cyclin-dependent kinase inhibitors, on muscle biopsies from 14 patients with polymyositis, dermatomyositis, inclusion body myositis and HIV-associated myositis. Our data demonstrate that inflammatory cells are immunoreactive for bcl-xl, p16 and p57, three apoptosis-preventing proteins. Hence, we assume that these proteins might protect T cells from apoptotic nuclear changes. Our results could explain the non-self-limiting nature of inflammatory myopathies.
