Fig. (1) Growth, morphological and functional characterization of SA7K cells. (A) Normal epithelial morphology of SA7K cells, including dome formation; (B) Expression of the proximal tubule marker aminopeptidase N (CD13) in SA7K cells; (C) Extended population doublings in ZFN-modified SA7K versus HPTC cells; (D) Uptake of Albumin-FITC; (E) Response to Parathyroid Hormone (PTH); (F) GGT Activity in HPTC versus SA7K cells. Scale bar: 50 µm.