Improved methods of influenza virus propagation. II. Characteristics of cell culture and allantoic virus preparations.
Regular reproduction of influenza A virus with infectious titres of 7.4--8.5 log EID50/0.2 ml was observed in roller bovine embryo kidney cell cultures. The haemagglutinating activity of the cell culture preparations was 8-33-fold lower than that of the allantoic preparations, the infectivity being similar. Cell culture preparations of influenza A/Victoria/35/72 and A /Leningrad/538/74 viruses were markedly immunogenic in laboratory animals and antigenically active in complement fixation (CF) test. The CF activity of liquid and lyophilized preparations remained unchanged for 12--13 months (the period of observation). The stability of infectivity of lyophilized cell culture virus preparations was similar to that of allantoic virus preparations.
Improved methods of influenza virus propagation. II. Characteristics of cell culture and allantoic virus preparations. Regular reproduction of influenza A virus with infectious titres of 7.4--8.5 log EID50/0.2 ml was observed in roller bovine embryo kidney cell cultures. The haemagglutinating activity of the cell culture preparations was 8-33-fold lower than that of the allantoic preparations, the infectivity being similar. Cell culture preparations of influenza A/Victoria/35/72 and A /Leningrad/538/74 viruses were markedly immunogenic in laboratory animals and antigenically active in complement fixation (CF) test. The CF activity of liquid and lyophilized preparations remained unchanged for 12--13 months (the period of observation). The stability of infectivity of lyophilized cell culture virus preparations was similar to that of allantoic virus preparations.