An infectious pancreatic necrosis virus isolated from common dab Limanda limanda previously affected with X-cell disease, a disease apparently unrelated to the presence of the virus

Infectious pancreahc necrosis (IPN) virus has been isolated for the flrst time from common dab Lirnanda limanda L. during a search for a possible viral etiology of the X-cell condition.The virus was identified by electron microscopy as a 60 nm diameter spherical particle.It produced IPNtypical cytopathic effects in chinook salmon embryo (CHSE-214) cells and was neutralized by rabbit IPN-antisera.Experimental inoculations of dab with the virus failed to generate X- cell lesions, further supporting the currently held view that Xcells are not virally transformed fish cells.The nature and origin of X-cell disease, a condition documented in over 20 species of marine teleosts, is unknown despite the considerable research efforts invested in it over the past decade (for review see Mix 1986).The viral etiology of X-cells has been argued in the past (Peters et al. 1978(Peters et al. , 1981)), but no virus could be demonstrated to be associated with the condition in the Pacific Ocean (Ito et al. 1976, Wellings et al. 1976).In the present study, common dab Limanda limanda L. from the North Sea, some with gross X-cell lesions, others that had recovered from the condition, were surveyed for presence of virus.Methods and Results.Common dab were sampled during May 1986 off the coast of northeast Scotland.Approximately 100 fish with X-cell lesions were transported alive to the Marine Laboratory, Aberdeen, where they were transferred to tanks supplied with flowing filtered (but otherwise untreated) seawater at ambient temperature.The X-cell diseased fish were severely stressed from capture and transport, and 70 %