[Viral origin of Paget's disease of bone?]

The viral aetiology of Paget's bone disease was suspected by the finding, in 1974, of microcylindric paramyxovirus nucleocapsid-like inclusions in nuclei and cytoplasm of pagetic osteoclast. Paramyxovirus antigens were detected, using monoclonal antibodies, in the osteoclasts of pagetic lesions. Paramyxovirus RNA sequences were identified in Paget's bone tissue, predominantly in osteoclasts, using specific hybridization. However, these last results are conflicting because some reports failed to reproduce hybridization with Paramyxovirus. Nevertheless, Paramyxovirus could be responsible for the cytopathologic aspect of multinucleated osteoclasts for the stimulation of hyperexpression, in Paget's disease, of interleukin 6 and of c-fos oncogene known to enhance osteoclastic resorption activity.