Activity of Hydra Cells in vitro and in Regenerating Cell Reaggregates

Abstract

Hydra were disaggregated into single cells and maintained in a complex medium for a few days. The cells are capable of macromolecular synthesis, of processing RNA, and of carrying out the formation of a nematocyst capsule. Single cells can be centrifuged into aggregates which will develop into normal hydra. Changes in morphology and cell composition are described. Interstitial cells after a 1-day delay resume their normal mitotic and differentiation activity in the aggregates. The method provides new means for studying problems of cell differentiation in hydra.