Abstract
This study investigates the susceptibilities of the SPB cell line to fish viruses including giant seaperch iridovirus ( GSIV ‐ K 1), red sea bream iridovirus ( RSIV ‐ K u), grouper nervous necrosis virus ( GNNV ‐ K 1), chum salmon reovirus ( CSV ) and eel herpesvirus ( HVA ). GSIV ‐ K 1, RSIV ‐ K u and CSV replicated well in SPB cells, with a significant cytopathic effect and virus production. However, the cells were HVA and GNNV refractory. To examine the ability of SPB cells to stably express foreign protein, expression vectors encoding GNNV B 1 and B 2 fused to enhanced green fluorescent protein ( EGFP ) and GSIV ORF 35 L fused to D s R ed were constructed and introduced by transfection into SPB cells. Stable transfectants displayed different morphologies compared with SPB and with each other. EGFP ‐ B 1 was predominantly localized in the nuclei, EFPF ‐ B 2 was distributed throughout the cytoplasm and nucleus, and granular 35 L ‐ D s R ed was localized with secreted vesicles. The expression of EFPF ‐ B 2 in SPB cells produced blebs on the surface, but the cells showing stable expression of EGFP , EGFP ‐ B 1 or 35 L ‐ D s R ed showed normal morphologies. Results show the SPB cells and the transfected cells grow well at temperatures between 20 and 35 °C and with serum‐dependent growth. SPB cells are suitable for studies on foreign protein expression and virology.