The methods that make Hantavirus grow consist of inoculation into the experimental animals and cultured cells. The cultured cells, such as Vero-E6 and A549 cells, have been usually used for isolation of the virus and the animals, such as mice and
rats,
are used for large scale preparation of the virus so far. Furthermore, the cells can be used to maintain the virus and assay the infectivity and the animals can be used for the experiment of viral pathogenicity and challenge for assessment of
vaccine.
Apodemus mice, the own natural host of the virus, has been used for challenge test of Hantaan virus. However it has been pointed out to difficult handing and breeding the animal in laboratory, Therefore, we attempted to establish a new animal
model
for
challenge test at the time of isolation of Maaji virus which is a new hantavirus similar but distinct to Hantaan virus. In sucking hamster, the titer of Maaji virus and the lethality to mice of the virus were increased gradually in the titer and
lethality through passage by intracerebral (IC) inoculation. We tried to re-adapt this brain virus to lung of weanling hamster. The brain passaged virus was inoculation into weanling hamster intramuscularly. Again. the titer of the virus in lung
was
also increased by continuous passage of this virus. This facts could regarded as adaptation to new environment in which the virus proliferates. To identity the virus passaged in hamster with Maaji virus, both of the virus passaged in hamster
brain
and
lung were compared with Maaji virus (MAA-I) and Hantaan virus (HTN 76-118) by means of restriction fragment length polymorphism (RFLP) and slingle strand conformation polymophism (SSCP), As a result, we conclude that Maaji virus could be adapted
successfully to weanling hamster throught this passage strategy, Utilizing this adapted Maaji virus strain, hamster model is able to be used for challenge test in hantaviral vaccinology and further experiments utilizing hamster system as a rather
available and convenient lab animal are expected.
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