[Synthesis of measles virus proteins in chronically infected human cell cultures].

Synthesis of measles virus proteins in primary and chronic infection of L-41 and HEP-2 cells was studied by radioimmunoprecipitation test and polyacrylamide gel electrophoresis. Synthesis of measles virus main structural proteins, H, P, NP, and M, was found to occur in chronically infected cells. Persistence of measles virus in the systems under study was shown not to be accompanied by changes in electrophoretic mobility of virus polypeptides as compared with proteins synthesized in primary infection. NP protein of the original virus, however, differed significantly from NP protein of the persisting virus in its charge which indicated aminoacid replacements apparently due to mutations of the appropriate region of the virus genome. The mechanism of measles virus persistence in these systems was shown not to be associated with disorders in matrix protein synthesis. Use of monoclonal antibodies in fluorescent antibody technique and radioimmunoprecipitation revealed the stability of a number of antigenic determinants in persisting measles virus in L-41 and HEP-2 cell cultures.