Microcapillary Bioreactor for Growth of Human & Animal Tissues

Researchers at Arizona State University have designed a bioreactor that maintains an optimal physiological environment for tissue to remain viable ex vivo and carry on functions that are otherwise difficult when undergoing static growth in a Petri dish. This invention mimics the body's circulatory system environment and allows precise ex vivo control. The factors that limit the growth of cells in a three-dimensional mass are the ability to obtain nutrients and oxygen in addition to the ability to remove waste and carbon dioxide. In an organism, the circulatory system normally provides these exchanges. The purpose of this device is to grow tissues in a three-dimensional mass, in a fashion similar to the way they grow in-vivo. There have been a number of approaches for growing tissue/cells in a three-dimensional mass. Previous bioreactors, however, are not capable of allowing the placement and removal of large aggregates of cells from among the fibers because there is no means of inserting the three-dimensional mass of tissue. A prototype bioreactor vessel for the purpose of growing cells in a three-dimensional matrix/scaffold environment has been built and tested. This new bioreactor incorporates the following features and specifications: " Easy placement of tissue onto the inner scaffolding. " Allows for easy viewing of cells while on standard microscope stages. " Easy syringe injection of fluids into the chamber's extra-lumenal space. " Easy replacement of microcapillary fibers and sterilization of the whole assembly for reuse.The bioreactor has numerous diagnostic and therapeutic applications. It can be used to culture biopsy specimens. In fact, the researchers have aready been successful in culturing glial cells from human brain. In another application, the bioreactor can be used to culture embryos. Women that are going to undergo chemotherapy, or radiation treatments often have ovulated eggs removed and cryopreserved. This is done in order to provide eggs that can be fertilized and used to produce children after treatment. Alternatively ovarian tissue fragments can be cultured in the bioreactor.The Bioreactor also offers several distinct benefits as a research tool. Tissues can be placed in the bioreactor with an experimental drug, for instance, and the histological changes could be photographed under a microscope as frequently as desired. Thus there would be a reduction in the number of animals sacrificed and a reduction of general experimentation costs for drug screening.