Renal cell cultures for the study of growth factor interactions underlyingkidney organogenesis

The present study was performed in four renal cell lines to evaluate their capability to: (1) produce and express transforming growth factor alpha (TG F alpha), its respective receptor, the epidermal growth factor receptor (EG Fr) and the small G protein, RhoA, and (2) exhibit morphogenetic properties when grown on Matri-cell substrates. The cell lines were derived from norm al (Madin-Darby canine kidney cells), embryonic (SK-NEP-1 and 293 cells), a nd cancerous (human renal adenocarcinoma cells) kidneys. TGFa messenger rib onucleic acid, evaluated by a nonradioactive in situ hybridization techniqu e, was found to be expressed in all the cell lines. Large amounts of TGF al pha peptide were observed in all four cell, lines, while EGFr was highly ex pressed only in cancerous ACHN and embryonic-tumor SK-NEP-1 cells. RhoA pep tide was found in appreciable amounts in SK-NEP-1 and 293 cells (compared t o the other two cell lines). The morphogenetic properties of the four cell lines were assessed, by culturing them on Matri-cell dishes: SK-NEP-1 cells alone were found to grow in three-dimensional structures forming clusters and worm-like cellular aggregates. This feature was displayed by SK-NEP-1 c ells but not by the other three cell lines, and may be connected with the c ontemporary presence of RhoA, EGFr, and TGF alpha found in significant amou nts only in the SK-NEP-1 cell line.