STUDY ON INTERFERON PRODUCTION IN GRASS CARP (CTENOPHARYNGODON IDELLUS) FOLLOWING INFECTION WITH HAEMORRHAGIC VIRUS
Shao Jianzhong Qian Kaixian Xiang Lixin Li Yanan Mao Shujian (College of Life Science, Zhejiang University, Hangzhou 310012)
The interferon activity was detected in sera of grass carp (Ctenocpharyngodon idellus) following infection with haemorrhagic virus by cell pathological effect inhibition assay. When the grass carp was induced at the temperature of 25℃ for 3 days, the serum samples provided the best interferon titres, its antiviral activity assayed on grass carp cells was higher than 11.08±0.58 (X±SD) log 2 units. Biochemical studies showed that the grass carp serum interferon was not sedimented at 100000g for 2 hours, exhibited stability to pH2-pH10 and heat (56℃), it was resistant to DNase and RNase, but was sensitive to trypsin, glucosidase and NaIO 4. Its inhibitory effect on virus replication was dependent on the process of cellular RNA and protein systhesis. It was able to inhibit different kinds of virus in the cells of grass carp, but failed in human, mammalian, avian and shellfish cells. The result showed that the grass carp serum interferon was specific to fish cells and viruses. Its biological characteristics were consistant with that of high vertebrate interferon.