Fight Aging!

Today I thought I'd point out an interesting article on a Japanese research group that works on tissue engineering of brain and eye structures. There is already considerable specialization in this young field: making headway in deciphering the chemical and gene expression instruction sets for cells and tissue growth is a massive undertaking, and it is different for every type of tissue in the body. There is enough here to keep a growing community of researchers busy for decades yet.

Tissue engineering: The brainmaker

Yoshiki Sasai, a stem-cell biologist at the RIKEN Center for Developmental Biology in Kobe, Japan, [has] impressed many researchers with his green-fingered talent for coaxing neural stem cells to grow into elaborate structures. As well as the optic cup, he has cultivated the delicate tissue layers of the cerebral cortex and a rudimentary, hormone-making pituitary gland. He is now well on the way to growing a cerebellum - the brain structure that coordinates movement and balance.

Sasai's work is more than tissue engineering: it tackles questions that have puzzled developmental biologists for decades. How do the proliferating stem cells of an embryo organize themselves seamlessly into the complex structures of the body and brain? And is tissue formation driven by a genetic program intrinsic to cells, or shaped by external cues from neighbouring tissues? By combining intuition with patient trial and error, Sasai has found that it takes a delicate balance of both: he concocts controlled environments that feed cells physical and chemical signals, but also gives them free rein to 'do their thing' and organize themselves into tissues.

What does one do with the ability to tissue engineer a brain? This will be possible not too many years from now. It's not as obviously useful as the ability to engineer a heart, as the brain can't be replaced outright in the same way - although that said it seems possible, based on present knowledge, for a least a few small portions of the brain to be successfully transplanted without affecting the mind. Not every part of the brain is greatly involved in the data and processing mechanisms that make up the self. But this seems as though it will be far harder than transplanting any other organ elsewhere in the body, and hard enough that parallel lines of research into repairing tissue in situ through stem cells and signaling manipulation may win out from the outset.

So the likely primary benefit resulting from the sort of work carried out by Sasai's group will be knowledge: information that can be applied to the development of ways to rebuild damaged brain tissue in place rather than building outside the body and then undergoing a transplant operation.