Verification of conditionally immortalized podocyte cell cultures from both wild-type and Alport mice. Cell lines were derived as described in Materials and Methods. A and C: Representative phase-contrast fields of undifferentiated podocyte cell cultures from wild-type and Alport mice, respectively. B and D: Representative fields of differentiated cells from these same mice, respectively. Note the typical arborized phenotype of the differentiated cells. Cultures from wild-type (E, G, and I) and Alport (F, H, and J) were further confirmed by positive immunostaining for both nephrin (E and F), CD2AP (G and H), and WT-1 (I and J) confirming that the cultures are indeed podocytes.