Rodent Kidney Explant Culture and Establishment of Primary Ureteric Bud Epithelial Cell Culture.

The developing kidney is a widely used model system to study mammalian organogenesis. Renal differentiation is orchestrated by reciprocal inductive tissue interactions among mesenchyme, stroma, and epithelium. Branching morphogenesis of epithelial ureteric bud promotes not only embryonic kidney growth and 3D patterning but also induces mesenchyme-to-epithelium transitions within the surrounding nephron progenitor pool, thereby ensuring nephron formation required for functional filtration. Critical cell fate decisions within all three tissue layers, epithelium, mesenchyme, and stroma, underpin a dynamic balance between progenitor self-renewal and differentiation equilibrium. These complex, multilayered regulatory interactions are inherently dependent on the structural integrity of the organ, making intact kidney models essential for studying morphogenetic processes and cellular behaviors in their native context. Kidney organ culture methods provide insightful platforms for visualizing developmental processes and dissecting morphological, cellular, and molecular mechanisms that govern renal differentiation. A variety of kidney culture methods exist, each offering distinct advantages. In this article, we detail the establishment of a traditional Trowell-type air-liquid interphase culture system for in vitro kidney development. To enhance the resolution of cellular and molecular analyses, we also describe the setup of a primary ureteric bud epithelial cell culture, which enables targeted investigation of epithelial-specific mechanisms. Finally, we demonstrate that the traditional kidney organ culture technique is applicable to the embryonic kidney of a novel model organism, the spiny mouse (Acomys dimidiatus). This opens interesting innovative avenues for stem cell and regeneration research, as Acomys has a remarkable functional repair capacity across several organ systems studied to date.