Restriction of virus-specific protein synthesis in a persistent paramyxovirus infection.

Synthesis of virus-specific proteins in a persistent, nonproductive paramyxovirus infection derived from the peripheral blood leukocytes of a patient with subacute sclerosing panencephalitis (SSPE) was investigated. The persistently infected cells expressed cytoplasmic virus-specific antigens and generated paramyxovirus nucleocapsids throughout long-term passage. When analyzed by specific immunoprecipitation and sodium dodecyl sulfate-polyacrylamide gel electrophoresis, most of the virus structural proteins were synthesized in acutely infected cells, but only three of the proteins could be readily detected in persistently infected cells. The two structural proteins whose synthesis was most clearly restricted had molecular weights of 69,000 and 41,000 daltons and represented the putative HN and M virus proteins. The similarities between the restriction of virus protein synthesis in this system and that reported previously for other persistent paramyxovirus infections derived from SSPE suggest that a common mechanism may be involved in the maintenance of such infections.