(P 357) The Bioengineered Renal Tubule

Introduction: Bioengineered renal tubules can be used to support endocrine and metabolic renal functions in chronic kidney patients. However, proliferating renal tubule epithelial cells rapidly loose their differentiated phenotype during culture. Our goal is to maintain highly differentiated primary human tubule epithelial cells (PTECs) by culturing the cells on a synthetic scaffold under perfusion conditions. We evaluated the viability and phenotype of PTECs that were cultured on microporous polycarbonate filters and on electrospun supramolecular ureido-pyrimidinone (UPy)-modified polycaprolactone meshes in a commercial perfusion culture system for 7 days. Results and Discussion: Although cells remained viable on both materials throughout the culture period, PTECs that were cultured on the electrospun meshes had a more differentiated phenotype with maintained gene expression of SGLT-1, PEPT-1, OAT-3, NaPi and AQP-1 genes. Perfusion culture did not modulate the gene transcription profile of these cells. However, perfusion culture improved the integrity of the monolayer on electrospun supramolecular polycaprolactone material as demonstrated by electron microscopy. In these samples also enhanced activity of the brush border enzyme alanine aminopeptidase was seen, whereas the activity of other brush border enzymes remained low. Conclusion: We conclude that electrospun supramolecular UPy-modified polycaprolactone meshes are very suitable substrates for renal epithelial cell monolayers and that perfusion culture can further improve the quality of the monolayer. Work is in progress to investigate the effect of long-term perfusion culture, as well as the use of bioactive culture substrates, on renal epithelial cell viability and function.