Another modest advance in stem cell science is noted in a Japanese paper, one of many on the way to developing a comprehensive repair kit for the aging human body:

Researchers have created cerebral tissue from human embryonic stem [ES] cells, an achievement thought likely to lead to a breakthrough in tackling Alzheimer's disease as well as pave the way for new regenerative treatments and other drugs, The Yomiuri Shimbun has learned.

Yoshiki Sasai, a group director of the RIKEN Center for Developmental Biology, said the tissue also can be created using induced pluripotent stem (iPS) cells. ... Sasai's group solidified about 3,000 human ES cells into balls 0.2 millimeter in diameter, added material that helped them develop into nerve cells, and cultured them for 50 days. The balls grew into mushroomlike objects one millimeter to two millimeters in diameter. Four types of nerve cells arranged in layers, which appeared very similar to those found in the cerebral cortex of a fetus, were observed inside each of the mushroom-shaped objects. The nerves also sent out electrical signals and showed other functional capacity.

Sasai said brain tissue can be created in the same way using human iPS cells. He said he planned to attempt to create six-layered tissue, far closer in structure to adult brain tissue. "This achievement will enable us to forge ahead with research into the adverse reactions caused by drugs as well as develop new vaccines," Sasai said. "It will lead to treatment capable of regenerating cerebral nerves."

There is much that could be done to lengthen life with the fully developed technology to generate new, undamaged tissue as needed. For all that, it is far from the be-all and end-all of longevity science - just one necessary technology of many - but it is encouraging to see the pace of development accelerating in the tissue engineering field in recent years.