In vivo tissue engineering: dreams for the future

Abstract

Both tissue-engineered organs and hybrid artificial organs are considered to be candidates for the satisfaction of future hopes. The author has been engaged in developing vascular prostheses-neointima formed on vascular prostheses was a product of tissue engineering in vivo. On the basis of the author's experiences, the advantages of in vivo tissue engineering technologies for future artificial organs and dreams for the future are described. The use of primitive young cells is an important point; they proliferate easily and can differentiate along with their environment. They also synthesize various kinds of cytokines and growth factors, which are useful for tissue engineering. Combined use of undifferentiated cells and growth factors can induce organogenesis, so we can aim for the creation of new organs in vivo. The rejuvenation phenomenon of cells, i.e., blastogenesis, is also useful. Extracellular matrix can control cell differentiation, migration, and formation of cell communities, so we must learn to modify extracellular matrices. We humans have an extremely important legacy in our bodies, although we do not know how to use it. We have accumulated many genes during our evolution, and such genes do not become extinct. Therefore we have many genes from our primitive ancestors. These primitive creatures had an extremely strong capability for tissue repair, and we must find a way to make practical application of these dormant traits. In the future human beings will be able to learn how to control and apply them for in vivo tissue engineering technologies.