The goal of tissue engineering is to repair or replace portions/ whole tissue with material that is able to perform the original function of that particular tissue whether biochemical, structural or both. This requires a well-developed understanding of not only the cell but cell-cell interactions and communication. Engineered tissue requires two main components: progenitor cells and a scaffold.
There are a number of different cell types we can start with. This list includes fibroblasts, chondrichthyes, osteocytes and, mesenchymal cells. These cells can come from many different sources whether from the same organism or a donor.
The scaffold is the synthetic part of the engineered tissue. It must be able to allow for cell attachment, enable diffusion of nutrients as well as chemical signals, provide mechanical stability and guide cell development. It must of course be biocompatible. In some cases having a biodegradable scaffold is ideal. The scaffold can be made of collagen, fibrin, polysaccharide, GAGs, polyesters(PLA), puramatrix, and also decellularised tissue extract. Methods for preparing scaffolds include nano fiber self assembly, textile, solvent casting, particulate leaching, and gas foaming techniques.
After the cells have been seeded into the scaffold it is submerged into a bath of growth factors and nutrients until the tissue is ready for implantation or whatever its end goal is. Some applications for engineered tissue are: artificial skin, vessels, cartilage, bone, pancreas, trachea and bladder.