Mitsuhashi J.

In Vitro Cell Dev Biol Anim. 1998 Sep;34(8):619-21. doi:10.1007/s11626-996-0007-9

Polyamine as a growth promoter for cultured insect cells.

At least one of putrescine, spermidine and spermine at 2 µg per 1000 ml need to be in the culture medium of NIH-SaPe-4 cells (from the fly Boettcherisca peregrina) could be passaged more than 10 times.