Isolated populations of adult renal cells and methods of isolating and using same

A method for forming tubular structures in the kidney of a subject in need thereof, comprising:

• expanding human kidney epithelial cells from a human adult kidney in a first culture medium under adherent conditions, wherein the first culture medium is a serum containing medium comprising at least one growth factor comprising IMDM supplemented with 10% FBS, 1% L-glutamine, 1% Pen-Strep, and growth factors:
• 50 ng/ml of bFGF, 50 ng/ml of EGF, and 5 ng/ml of SCF;
• culturing the cells in a second culture medium under non-adherent conditions, thereby generating a plurality of nephrospheroid cells, wherein the second culture medium is a serum free medium comprising 500 ml DMEM:F12 in a 1:1 ratio, 1% pen-strep, 2 ml B27 supplement, 4 μg/ml heparin, 1% non-essential amino acids, 1% sodium pyruvate, 1% L-glutamine, 1 ml lipid mix, 5 ml of 100× N2 supplement, 10 ng/ml FGF, 20 ng/ml EGF, and 5 ml growth factor mix;
• wherein a 200 ml solution of growth factor mix comprises 100 ml DMEM:F12, 4 ml of 30% glucose, 200 mg transferin, 50 mg insulin in 20 ml of water, 19.33 mg putrescine in 20 ml ddw, 200 μl of 0.3 mM sodium selenite, and 20 μl of 2 mM progesterone;
• isolating a population of nephrospheroid cells from the second culture medium;
• and
• administering to the subject a therapeutically effective amount of the isolated nephrospheroid cells by injection to a damaged kidney of the subject.