Tissue engineering bioreactors

With the advent of tissue engineering over a century later (Langer and Vacanti 1993), bioreactors were again needed to provide precise control of the culture microenvironment and successfully guide the growth of cells in three-dimensional (3D) scaold systems into viable tissues. In multicellular tissues, the complexity of cell-cell interactions makes it considerably more challenging to correlate the eect of experimental parameters with any single outcome measure of “functionality” in the resulting tissue. Indeed various general criteria (e.g., cell number and viability) and tissue-specic properties (e.g., spatial organization of cells and matrix, as well as mechanical, biological, and phenotypic properties) are evaluated to determine successful tissue-engineering outcomes. As a result, the design of tissue engineering bioreactors has evolved signicantly over the last 20 years, yet the guiding principles remain unchanged.