Change of membrane fluidity in HeLa cells at an early stage of a poliovirus infection.

Poliovirus Sabin-1 was adsorbed to cultured cells which were spinlabeled with 12-doxylstearic acid. The cells were measured with an electron spin resonance spectrometer and the order parameters were obtained. Increasing order parameters with increasing amounts of the virus at 30°C were observed in HeLa cells (permissive to the virus) but not in mouse embryonal 3T3 cells (non-permissive to the virus). The change of membrane fluidity may be involved in modification process of the virus particle during its degradation.