A non-transmissible cytopathogenic effect of influenza virus in tissue culture accompanied by formation of non-infectious hemagglutinins.

Various strains of influenza virus produce a cytopathogenic effect in cultures of HeLa cells. The virus could not be passed in series. Virus partially or even completely inactivated with respect to infectivity by exposure to 37 degrees C. or ultraviolet light retained some of its cytopathogenic effect. No evidence has been obtained of an increase in infectious virus in HeLa cultures, but an increase in hemagglutinins and in both viral and soluble complement-fixing antigens became detectable during incubation. These virus materials apparently were not released from these cells prior to their destruction. These results suggested that HeLa cells are capable of supporting an incomplete reproductive cycle of influenza virus. The fact that radioactive phosphorus was readily incorporated into the hemagglutinin supplies strong evidence for this interpretation.