In vivo clonal analysis and the kidney: Implications to regenerative nephrology

During the past decades, our understanding of the way the kidney develops, functions, and responds to damage has grown exponentially. This has resulted from the combined use of various models, both in vitro and in vivo. Paramount to this process was the use of genetically manipulated mouse models (i.e., transgenic mice), representing the most studied organism and the basis for a significant portion of the knowledge gained about the mammalian kidney. In particular, these models are an effective means of delineating cellular lineages within the kidney during both steady state and disease and understanding how this may be translated to regenerative nephrology. Herein, we review the basic concepts of in vivo lineage tracing and present how this tool has provided answers to some of the most fundamental and important questions in kidney growth and regeneration in fetal and adult life.