Rojjer
mouse-to-mouse intranasal passage
一般传几代就会发现小鼠可以致死，
不过理想的mouse-adapted influenza A virus最好使得小鼠在7天可以全部死亡.
To prepare adapted virus to mice, lung-to-lung passages were performed. Briefly, the BALB/c mice were anesthetized and inoculated with 20 μl of the abovementioned
H5N1 viral suspension by intranasal drip. At the 3rd day after inoculation, the mice were sacrificed, andtheir trachea and lungs were taken out and washed 3 times with a total of 2 ml of phosphate buffered saline (PBS) containing 0.1% bovine serum albumin (BSA). The bronchoalveolar washings were collected and used for infecting the next batch of mice after removing the cellular debris by centrifugation .The lung-to-lung passages
were repeated at least three times and the adapted viruses were harvested, aliquoted, and stored in at -80°C.
reference:A single immunization with HA DNA vaccine by electroporation induces early protection against H5N1 avian influenza virus challenge in mice http://www.biomedcentral.com/1471-2334/9/17/