Cynomolgus Monkey Primary Proximal Tubular Epithelial Cells from Cell Biologics are isolated from Cynomolgus Monkey proximal tubular tissue and grown in gelatin pre-coated tissue culture flask with Cell Biologics’ Complete Growth Medium. Cells at passage 3 are harvested from flasks and cryo-preserved in vials. Each vial contains 0.5x106 cells per ml and is delivered frozen. Cynomolgus Monkey Primary Proximal Tubular Epithelial Cells from Cell Biologics are characterized by immunofluorescent staining with E-cadherin (Catalog No. 610182 from BD) or ZO-1 (Catalog No. 617300; from Life Technologies) antibodies. These cells are negative for mycoplasma, bacteria, yeast, fungi, HIV-1, hepatitis B and hepatitis C and can be expanded for 3-5 passages at a split ratio of 1:2 under the cell culture conditions specified by Cell Biologics. Repeated freezing and thawing of cells are not recommended.