Podocytes, cells of the visceral epithelium in the kidneys, are a key component of the glomerular filtration barrier. As such, they play a vital role in glomerular disorders, which are a major cause of chronic kidney disease. Examples of these disorders include focal segmental glomerulosclerosis, membranous glomerulonephritis, minimal change disease, and diabetic nephropathy.

The inventors have developed a conditionally-immortalized mouse podocyte cell line with tightly controlled conditional gene expression. The cell line has been conditionally immortalized through the introduction of the H-2Kb-tsA58 transgene, which is a temperature-sensitive mutant of the SV40T antigen. Inducible gene expression is tightly controlled through two introduced transgenes, podocin-rtTA and CMV-tTS, that produce a "Tet-on" system wherein gene expression is induced by tetracycline or doxycycline. The combination of the two transgenes for Tet-on gene expression has resulted in much tighter regulation and lower background expression compared to cells carrying the podocin-rtTA transgene alone.