A continuous cell line, PBLE, was developed from the adherent cells in a culture of peripheral blood leukocytes from the American eel, Anguilla rostrata. The cells were grown in Leibovitz's L-15 basal medium supplemented with 20% fetal bovine serum (FBS). Under normal culture conditions at 18 degrees C, the morphology of PBLE was fibroblast-like. The cultures have been subcultured over 80 times and have been cryopreserved successfully. These cells have a diploid karyotype of 38 chromosomes, survived temperatures from 5 to 36 degrees C, and proliferated at temperatures from 5 degrees C to at least 30 degrees C. PBLE underwent apoptosis in response to gliotoxin, but did not show a respiratory burst. Results suggest that PBLE may have arisen from a circulating mesenchymal stem cell. PBLE was susceptible to Chum salmon reovirus (CSV) and supported CSV replication. Therefore this cell line should be useful in studying eel specific virus-host interactions.