Experimental ependymomas: in vivo and in vitro morphology.

Abstract

Four primary tumors of rats diagnosed as ependymomas were explanted in vitro and transplanted into isogenic hosts. Transplanted tumors grew in the brain of the grafted animals within and in the border zone of the ventricles. Tumors in vitro, primary as well as transplanted, had uniform cellular components forming a dense network of bipolar and stellate single cells. The in vitro movement took place along and inside the filamentous protoplasmic processes. The significance of these results for the point of origin of experimental rat brain tumors is discussed.