ABSTRACT
Tissue engineering is a very promising approach for the treatment of a variety of medical conditions. Treatment of a disease or medical problem using this approach requires the availability of the appropriate cells and the creation of an arti˜cial support structure to contain them. The cells may be obtained from a variety of sources, for example, from an expanded population of the host’s own cells (perhaps genetically modi˜ed), from other compatible human donors, from animal sources, or even genetically engineered cell lines. The cells to be transplanted are then seeded into a polymeric scaffold or construct. The construct can then be placed within a bioreactor and then implanted in the patient at the appropriate time, as discussed in Chapter 9. However, with the exception of autologous cells, one of the major obstacles that must be overcome is rejection of the transplanted cells by the host’s immune system. The transplanted cells will be destroyed quickly by the host’s immune system unless they are immunologically similar to the host’s own cells (Benjamin and Leskowitz 1991).
