A Critical Aspect of Bioreactor Designing and Its Application for the Generation of Tissue Engineered Construct: Emphasis on Clinical Translation of Bioreactor

Usage of bioreactors in the field of tissue engineering has played a significant role in enabling a controlled and reproducible change in the formation of damaged tissue on being provided with specific factors. Owing to the scarcity seen in providing sufficient donor organs for transplantation there is a huge requirement for large-scale production of artificial organs. This cannot be achieved by static culturing since it does not provide an in-vivo three-dimensional (3D) microenvironment therefore tissue engineering plays a vital role in the development of artificial tissues and organs as per the clinical demands whereas bioreactors have served a major role in providing the artificial microenvironment required by the cells to grow further into a tissue and then into an organ. By providing the specific biochemical cues and mechanoresponsive stimuli the bioreactors turn to be very effective in generating transplantable organs. Apart from performing studies in a controlled manner aimed at understanding biological and physicochemical effects, bioreactors also ensure the safe and reproducible production of tissue-engineered constructs to achieve cost-effective large-scale production. The design criteria for bioreactors to be used in tissue engineering include optimal aspect ratio, proper aeration for the cells to proliferate, and agitation with reduced shear stress. The current review summarizes important aspects like Height/Diameter ratio or aspect ratio, shear stress, mechanical stress, aeration, agitation, oxygenation, etc. related to the design of tissue bioreactors, different types of bioreactors that are in use to date, and the reported pieces of literature to yield an overview on the existing concepts. It mainly focuses on the generation of 3D tissue constructs in various reactor systems specially designed for their culture and development along with their applications.