Introduction Among the various possible embodiements of Advanced Therapies and in particular of Tissue Engineering the use of temporary scaffolds to regenerate tissue defects is one of the key issues. The scaffolds should be specifically designed to create environments that promote tissue development and not merely to support the maintenance of communities of cells. To achieve that goal, highly functional scaffolds may combine specific morphologies and surface chemistry with the local release of bioactive agents.
Many biomaterials have been proposed to produce scaffolds aiming the regeneration of a wealth of human tissues. We have a particular interest in developing systems based in nanofibrous biodegradable polymers1,2. Those demanding applications require a combination of mechanical properties, processability, cell-friendly surfaces and tunable biodegradability that need to be tailored for the specific application envisioned. Those biomaterials are usually processed by different routes into devices with wide range of morphologies such as biodegradable fibers and meshes, films or particles and adaptable to different biomedical applications.
In our approach, we combine the temporary scaffolds populated with therapeutically relevant communities of cells to generate a hybrid implant. For that we have explored different sources of adult and also embryonic stem cells. We are exploring the use of adult MSCs3, namely obtained from the bone marrow for the development autologous-based therapies. We also develop strategies based in extra-embryonic tissues, such as amniotic fluid (AF) and the perivascular region of the umbilical cord4 (Wharton's Jelly, WJ). Those tissues offer many advantages over both embryonic and other adult stem cell sourcess. These tissues are frequently discarded at parturition and its extracorporeal nature facilitates tissue donation by the patients.
The comparatively large volume of tissue and ease of physical manipulation facilitates the isolation of larger numbers of stem cells. The fetal stem cells appear to have more pronounced immunomodulatory properties than adult MSCs. This allogeneic escape mechanism may be of therapeutic value, because the transplantation of readily available allogeneic human MSCs would be preferable as opposed to the required expansion stage (involving both time and logistic effort) of autologous cells.
Topics to be covered This talk will review our latest developments of biomaterials and scaffolds in combination with stem cells for cartilage tissue engineering.
Monteiro N, et al. J. Tissue Eng and Reg Med, DOI: 10.1002/term.1817.
Oliveira C. Biomacromolecules 2014;15(6):2196-2205.
Alves da Silva ML, et al. J. Tissue Eng Reg Med, DOI:10.1002/term.1812, 2015.
Costa-Pinto AR, et al. J. Tissue Eng Reg Med 2012;6:(9 Suppl. 2).
Acknowledgments It is acknowledged the Portuguese Foundation for Science and Technology for the financial support provided to the project Maxbone, PTDC/SAU-ENB/115179/2009. It is also acknowledged the RL2 – SCN - NORTE-01-0124-FEDER-000020, co-financed by North Portugal Regional Operational Programme (ON.2 – O Novo Norte), under the National Strategic Reference Framework (NSRF), through the European Regional Development Fund (ERDF) and the European Project Polaris.
Disclosure of Interest None declared