Development of a walleye cell line and use to study the effects of temperature on infection by viral haemorrhagic septicaemia virus group IVb

A cell line, WE-cfin11f, with a fibroblast-like morphology was developed from a walleye caudal fin and used to study the intersection of thermobiology of walleye, Sander vitreus (Mitchill), with the thermal requirements for replication of viral haemorrhagic septicaemia virus (VHSV) IVb. WE-cfin11f proliferated from 10 to 32 degrees C and endured as a monolayer for at least a week at 1-34 degrees C. WE-cfin11f adopted an epithelial shape and did not proliferate at 4 degrees C. Adding VHSV IVb to cultures at 4 and 14 degrees C but not 26 degrees C led to cytopathic effects (CPE) and virus production. At 4 degrees C, virus production developed more slowly, but Western blotting showed more N protein accumulation. Infecting monolayer cultures at 4 degrees C for 7days and then shifting them to 26 degrees C resulted in the monolayers being broken in small areas by CPE, but with time at 26 degrees C, the monolayers were restored. These results suggest that at 26 degrees C, the VHSV IVb life cycle stages responsible for CPE can be completed, but the production of virus and the initiation of infections cannot be accomplished.