CYTOLOGICAL STUDIES OF "BALLOON CELLS" OCCURRING IN THE EHRLICH ASCITES CARCINOMA

Abstract

Anomalous giant cells, termed "balloon cells", were found in a subline of the Ehrlich ascites carcinoma. The balloon cells remained in the supernatant when ascitic fluid was centrifuged at 17,000 r.p.m.The balloon cells were considerably larger than the regular tumor cells, and in their fully developed form the nucleus occupied a completely lateral position, resembling a signet-ring cell. The cytoplasm contained only a small number of lipid granules surrounding the nucleus; no vacuolization of the cytoplasm could be demonstrated. Mucoid substances in the cytoplasm were not accumulated. Mitochondrial activity was localized mainly around the nucleus. The uptake of tritiated thymidine in the nucleus indicated continued DNA synthesis by the balloons. They underwent mitotic division and contributed to the expanding tumor cell population.