Journal of the American Society of Nephrology
Hormones, Growth Factors, Cell Biology and Structure
A Conditionally Immortalized Human Podocyte Cell Line Demonstrating Nephrin and Podocin Expression
Saleem, Moin A.*; O’Hare, Michael J.†; Reiser, Jochen‡; Coward, Richard J.*; Inward, Carol D.*; Farren, Timothy*; Xing, Chang Ying*; Ni, Lan*; Mathieson, Peter W.*; Mundel, Peter‡
*Children’s Renal Unit and Academic Renal Unit, University of Bristol, Southmead Hospital, Bristol, UK; †LICR/UCL Breast Cancer Laboratory, London, UK; ‡Department of Medicine and Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, New York.
Correspondence to: Dr. Moin A. Saleem, Children’s Renal Unit and Academic Renal Unit, University of Bristol, Southmead Hospital, Bristol, BS10 5NB UK. Phone: +44-117-959-6048; Fax: +44-117-959-5438; E-mail: [email protected]
Accepted November 01, 2001
Received July 14, 2001
Abstract
ABSTRACT. Recent molecular insights have established the podocyte as a key component of the glomerular filtration barrier, and hence an important common pathway in proteinuric diseases. A conditionally immortalized human podocyte cell line has been developed by transfection with the temperature-sensitive SV40-T gene. These cells proliferate at the “permissive” temperature (33°C). After transfer to the “nonpermissive” temperature (37°C), they entered growth arrest and expressed markers of differentiated in vivo podocytes, including the novel podocyte proteins, nephrin, podocin, CD2AP, and synaptopodin, and known molecules of the slit diaphragm ZO-1, α-, β-, and γ-catenin and P-cadherin. The differentiation was accompanied by a growth arrest and the upregulation of cyclin-dependent kinase inhibitors, p27 and p57, as well as cyclin D1, whereas cyclin A was downregulated. These data are consistent with cell cycle protein expression during podocyte maturation in vivo. In conclusion, the development of this cell line provides a new tool in the study of podocyte biology, which will enable accurate assessment of the behavior of these complex cells in health and disease.