  Tissue Engineering concerns the three-dimensional cell growth so that
bio-artificial tissues could be created and used for transplantation. The
recently expressed concerns from the Tissue Engineering research community for
a re-direction of the research activities necessitate the proposition of new
methodologies. We propose a methodology that has to do with the simulation in
bioreactor systems of liver structures as are described in liver anatomy. I
this way the hepatocyte microenvironments that determine their function could
be re-created in vitro. The approach needs the use of hepatocyte aggregates as
entities to load the bioreactor systems. A new bioreactor, the microgravity
simulating rotation bioreactor, has been used for the preparation of cell
aggregates. Microcontact printing has been used to produce a patterned
surfaces. They were tested adsorbing BSA proteins, and will be used in future
for the mmobilization of cell aggregates in order to gain further understanding
of the role of cell heterogeneity in the cooperative behaviour of cells in
vitro.
