ARUP; ISBN: 978-0-9562121-5-3 - CMBBE 2012 - Cardiff University

5. DISCUSSION
The critical issue in microscale design is the facilitation of mass transport within 3D
matrices to control the efficiency of cell seeding. The inclusion of sufficiently sized
open pores and a well interconnected geometry improve diffusion throughout the
scaffold interior. Three-dimensional matrices with similar porosity but dramatically
different pore geometry, can yield different mass transport profiles [16]. It is important
to point out that the mass transport term has a control in the distribution inside the
scaffold and in the adhesion rate [15, 16].
In this study a controlled and reproducible cell-seeding methodology was proposed.
Experimental results obtained for fluorescent particles (using blood flow determination)
were compared with flow particles computational approach previously proposed. The
next step of this work will include the use of the cells live and evaluate the real process.
We are assuming that the fluorescent particles had a behavior similar to the blood cells
in media.
The experimental conditions were reproduced computationally, from control of microscale
using a regular scaffold. With a same model were predicted the cell seeding
process [15] but the experimental assessment was a limitation. For this new approach, a
transparent fluidic chamber was designed, and the process can be visualized. Live
videos will be used to calculate the particles velocities and trajectories, and a further
comparison with the magnitude obtained in the computational studies. This point
represented a significant advance for the futures studies of complex dynamic cell
seeding.
Changes of velocities experiment by the particles in the zones near the scaffold,
demonstrate the importance of controlling the structure and fluid environment. For a
high drag flow did not allow to particle deposition, similar to theory formulated by
Wendt [2]. The scaffold design used is also important; in this study a regular and
orthogonal scaffold was used. Given the difficulty of the particles to penetrate inside the
pores, the BP had higher densities compared to the IC zone.
6. CONCLUSIONS
Cell seeding plays a critical role in the quality of custom-made TE constructs. Reliable
techniques are required to validate the different seeding conditions including the initial
suspended cells to the successfully attaching cells. In this study a new approach was
proposed based on computational and experimental methods. Both methods are based
on the particles flow, and its capacities and limitations were compared with an in vitro
dynamic seeding.
7. ACKNOWLEDGEMENTS
The present study was funded by the European Research Council (ERC grant agreement
No. 258321).
8. REFERENCES
1. I. Martin, T. Smith, and D. Wendt, Bioreactor-based roadmap for the translation of
tissue engineering strategies into clinical products., Trends Biotechnol, 2009. Vol.
27, 495-502,