Search for Chemically Defined Culture Medium to Assist Initial Regeneration of Diseased Renal Parenchyma After Stem/Progenitor Cell Implantation

Before an intended implantation stem/progenitor cells are usually kept in the beneficial atmosphere of a selected culture medium. However, after implantation the situation is drastically changing for them. Yet stem/progenitor cells must stand the harmful fluid environment within a diseased organ. In this coherence it is unknown, to which degree alterations in molecular composition of interstitial fluid can influence the initial regeneration of parenchyma. To obtain first insights in the sensitivity against changes in fluid composition, renal stem/progenitor cells were mounted within a polyester interstitium for perfusion culture. To model interstitial fluids different chemically defined culture media all including aldosterone were administered continuously for 13 days. Then morphological quality of generated tubules was registered by light and transmission electron microscopy. Culture of stem/progenitor cells in earlier approved Iscove´s Modified Dulbecco´s Medium served as internal standard. These experiments revealed generation of numerous tubules. In comparison, application of Williams’ E Medium, Basal Medium Eagle, McCoy’s 5A Modified Medium and Medium 199 produced only a lean quality of generated tubules, since contained cells exhibited numerous vacuoles. In contrast, administration of Leibovitz’s L-15 Medium and CO2 Independent Medium showed unexpected promoting effects on development of tubules. In this series numerous and intact tubules without formation of an excess of vacuoles were detected. In consequence, Leibovitz’s L-15 Medium and CO2 Independent Medium appear as challenging candidates to be tested in future for implantation in combination with stem/progenitor cells.