Many labs are either working with or have HEK293 cells frozen back in their repository. HEK293 embryonic kidney cells were cultured from an aborted fetus by Alex van der Eb, a researcher in Holland. Were you aware that they might not actually be of kidney cells and rather of neuronal origin. The cells also made Frank Graham, a researcher with van der Eb, famous for discovering that you could transfect some DNA if you just toss some calcium phosphate in with them.
A scientist by the name of Gerry Shaw was trying to stain 293's with a monoclonal antibody that he created to beta-adrenergic receptor kinase 1 (beta-ARK) which should be expressed in the cells. Wanting to be a proper scientist, Shaw wanted to have a negative control for staining, so he grabbed a neurofilament antibody, which should not stain a kidney cell line right? WTF this and other neurofilament antibodies were able to stain the cells! Scratching your head right, so was Shaw. Using microarray data, it was shown that 293's expression pattern of neuronal genes similar to that of other neuronal cell lines.
So if you are wanting an in vitro model for kidney research, you might want to go get another cell line.