Erythropoietin production in long-term cultures of human renal carcinoma cells : The role of cell population density |
| |
Authors: | Masamichi Hagiwara I-Li Chen James W Fisher |
| |
Institution: | Departments of Pharmacology and Anatomy, Tulane University School of Medicine, New Orleans, LA 70112, USA |
| |
Abstract: | The present studies report the maintenance of erythropoietin (Ep) production in long-term cultures of a human renal carcinoma from a patient with erythrocytosis. The renal carcinoma cells were grown and maintained in monolayer cultures for 7 months. They were serially passaged every 2-3 weeks when the cultured cells reached confluency. Ep levels measured with a sensitive radioimmunoassay in the spent culture media of the cells in the stage of semiconfluent or confluent density were less than 20 and 30 mU/ml, respectively, throughout the period of 15 successive passages. However, when the renal carcinoma cells were maintained in culture without passage after reaching confluency, Ep levels in the spent media of these cells reproducibly showed an exponential increase to more than 300 mU/ml at the time of saturation density. The importance of cell population density in Ep production by the renal carcinoma cell cultures was further confirmed by the observation that the cultures with higher seeding density reached confluency earlier and began an exponential increase in Ep production sooner than those cultures with lower seeding density. |
| |
Keywords: | To whom offprint requests should be sent Address: Department of Pharmacology Tulane University School of Medicine 1430 Tulane Avenue New Orleans LA 70112 USA |
本文献已被 ScienceDirect PubMed 等数据库收录! |