Ecdysteroids induce morphological changes in continuous cell lines of Lepidoptera

Abstract
In the continuous cell lines of the LepidopteraTrichoplusia ni (TN-368) andSpodoptera littoralis (HPB-SL-26), ecdysone and 20-hydroxyecdysone cause a series of morphological changes: some cells aggregate, elongate and extend long thin processes. The extent and rapidity of changes are dose dependent, 20-hydroxy-ecdysone being much more active then ecdysone. The continuous cell lines ofS. littoralis (UIV-SL-573) andS. frugiperda (IPLB-SF-21) were much less responsive to the presence of the ecdysteroids.