Titanium dioxide ceramics control the differentiated phenotype of cardiac muscle cells in culture

A new approach, the cultivation of heart muscle cells on biocompatible scaf folds made from titanium dioxide ceramics was established to provide a mech anism for in vitro engineering of a vital heart tissue. Terminally differen tiated ventricular myocytes isolated from hearts of adult rats were kept in primary culture for long periods of time and used as an experimental model , The microenvironmental properties of titanium dioxide ceramics helped to maintain the tissue-like structural organisation of the cardiac cells in vi tro, Coating of the cell substrata with fine-grained titanium dioxide ceram ics imitating cell surface topography favoured the formation of focal adhes ion complexes in the ventral plasma membrane of cardiomyocytes. It also pro moted the cellular expression of vinculin, a protein that connects the ECM integrin receptors to the network of cytoplasmic filaments; which define ce ll shape. This topographical reinforcement of cell-material interactions le d to stabilisation of the molecular linkage between the extracellular conta cts and the intracellular cytoskeleton and thus assisted the preservation a nd maintenance of the heart muscle cell differentiated phenotype in long-te rm primary culture. The results of this work demonstrate a promising pathwa y for the regulation of cellular organisation in vitro by local geometric c ontrol. (C) 2000 Elsevier Science Ltd. All rights reserved.