Tubulogenesis from isolated single cells of adult mammalian kidney: clonal analysis with a recombinant retrovirus

H. D. Humes, J. C. Krauss, D. A. Cieslinski and A. J. Funke Department of Internal Medicine, Veterans Affairs Medical Center, Ann Arbor, Michigan, USA. The adult mammalian kidney tubule epithelium exists in a relatively dormant, slowly replicative state but has a large potential for regenerative morphogenesis following severe ischemic or toxic injury. Under selective serum-free growth conditions, which included epidermal growth factor and retinoic acid, a subpopulation of renal proximal tubule cells isolated from adult rabbit kidney were grown in cell culture. These cells possessed two important characteristics: 1) an ability to differentiate morphogenically into tubule structures when grown in three-dimensional collagen gels and 2) a high capacity for self-renewal, since cell lineage analysis with a recombinant retrovirus demonstrated that in vitro tubulogenesis arose from clonal expansion of a single cell. Thus individual cells in the adult kidney have retained the ability for kidney tubulogenesis in vitro.