VIRAL ORIGIN OF PAGETS-DISEASE

The viral aetiology of Paget's bone disease was suspected by the findi ng, in 1974, of microcylindric paramyxovirus nucleocapsid-like inclusi ons in nuclei and cytoplasm of pagetic osteoclast. Paramyxovirus antig ens 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 hybridizat ion. However, these last results are conflicting because some reports failed to reproduce hybridization with Paramyxovirus. Nevertheless, Pa ramyxovirus could be responsible for the cytopathologic aspect of mult inucleated osteoclasts and for the stimulation of hyperexpression, in Paget's disease, of interleukin 6 and of c-fos oncogene known to enhan ce osteoclastic resorption activity.