Grace´s line of Antheraea eucalypti ovarian cell has been adapted by Suitor to a medium consisting of Grace´s insect cell culture medium(GMA) plus some additives.
A homogenate of a Japan strain of JEV(JaGar) isolated from mosquito and Korean strain of JEV (HM81) isolated from suckling mice, both with mice brains were used as inoculums. Virus-cell culture was carried out at 28°C and fresh hemolymph in GMA was added usually after 7, 14 and 21st, days in order to maintain the cells over period of 5 weeks for completion of the tests. Virus-cell mixture were prepared as serial ten-fold dilutions in phosphate buffered saline and 0.5% bovine albumin, 0.03 ml of virus emulsion was inoculated intracerebrally into weaning mice to determine LD50.
Cytopathic effect was not seen during the period of time. In JaGar, maximum peak of the virus titre was reached on days of 35th, in the course of-´the 7 weeks culture and in HM-81, on days of 21st, during the 5 weeks culture. There may be some difference in infectivity between HM-81 and JaGar strains against the cells.
This result suggest that several type of cells might be clonizing for the purpose of the studying´ more detail.
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