Under physiological conditions, resident cells of each tissue or organ secrete an optimal tissue-specific extracellular matrix (ECM) with a well-defined bio-structure.
Biological scaffolding materials can be produced via decellularisation of whole organs or portions, obtaining the native ECM. In the context of regenerative medicine and in-vitro models, decellularised matrices (dECMs) serve as a supportive framework and microenvironment for cells during-growth and differentiation. Focusing on liver as our target organ, we have developed and optimised several procedures to obtain well-characterised and reproducible decellularised matrices (dECMs) which preserve architecture and composition of the native ECM.
Physical methods and chemical detergents are used in combination to remove cellular components. The decellularised state of the resulting structure is confirmed by histological analysis and DNA quantification. The dECMs are then structurally and chemically characterised and may be used as scaffolds for cell cultures or further processed to obtain tissue derivatives, such as solubilised or powdered forms to obtain tissue-derived ECM gels or to include in hydrogel-based complex systems (nano-in-micro concept). To preserve a stable off-the-shelf scaffolding material, sterile dECMs can be hydrated and stored at -20°C or dehydrated and stored at room temperature.
Figure: H&E staining micrographs of liver samples decellularised using 3 to 5 days long immersion and agitation treatments involving no detergents (DF), non-ionic (NI) or ionic (I) detergents. There is a progressive shrinking of lobule dimensions with time and the intra-lobular matrix of the ionic family is clearly eroded. Scale bar 200 micron.
G. Mattei, V. Di Patria, A. Tirella, A. Alaimo, G. Elia, A. Corti, A. Paolicchi and A. Ahluwalia, “Mechanostructure and composition of highly reproducible decellularised liver matrices”, Acta Biomaterialia, vol. 10, no. 2, pp. 875-882, 2014