Abstract
The life cycle of enveloped viruses is intimately associated with, and influenced by, host cell membrane organization, which is altered by hyperthermia. Hyperthermia-modified Moloney murine leukaemia virus (M-MuLV) release, protein production and intracellular protein processing in a chronically infected cultured murine cell line, C9CL98 (C9). Both 44°C/45 min and 42–8°C/135 min substantially decreased cell-free viral env protein 8–48 h postheating, but virus release and cellular viral protein content increased following 42–8°C/25 min. Proteolytic processing of viral Pr65 gag precursor to p30 gag protein, normally observed within unheated C9 cells, was blocked for at least 8 h after 44°C/45 min. Virus released from heated C9 veils was as infectious to NIH/3T3 cells as was virus from control cells. Cells surviving exposure to 42 · 8°C/135 min became thermotolerant to decreased virus release from a second heating if delivered 10–48 h after the initial heating. The mechanism by which virus release is blocked after hyperthermia remains to be elucidated.