Patent ID: 7687240

Claim:
A method of identifying an attenuated respiratory syncytial virus (RSV) strain that produces high yields of RSV surface glycoprotein F when compared with the parent A2 strain, which method comprises: providing a eukaryotic cell culture; infecting the eukaryotic cell culture with a live, attenuated RSV strain at 30° C.; harvesting the infected cell culture; solubilizing the F protein in the harvested culture; and subsequently determining the glycoprotein F concentration in the harvested culture, wherein at least a five-fold increase in glycoprotein F concentration produced when the attenuated RSV strain is grown in the cell culture at 30° C. is an indication that the attenuated RSV strain produces high yields of RSV F glycoprotein when compared with the parent A2 strain grown at 37° C.