Japanese researchers make brain tissues from stem cells

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Japanese researchers make brain tissues from stem cells

Thu Nov 6, 5:05 AM

TOKYO (AFP) - Japanese researchers said Thursday they had created

functioning human brain tissues from stem cells, a world first that

has raised new hopes for the treatment of disease.

Stem cells taken from human embryos have been used to form tissues of

the cerebral cortex, the supreme control tower of the brain,

according to researchers at the government-backed research institute

Riken.

The tissues self-organised into four distinct zones very similar to

the structure seen in human foetuses, and conducted neuro-activity

such as transmitting electrical signals, the institute said.

Research on stem cells is seen as having the potential to save lives

by helping to find cures for diseases such as cancer and diabetes or

to replace damaged cells, tissues and organs.

The team's previous studies showed stem cells differentiated into

distinct cells but until now they had never organised into

functioning tissues.

" In regenerative therapy, only a limited number of diseases can be

cured with simple cell transplants. Transplanting tissues could raise

hopes for greater functional recovery, " the institute said in a

statement.

" Cultivated tissues are still insufficient and too small to be used

to treat stroke patients. But study of in-vitro cultivation of more

mature cortex tissues, such as those with six zones like in the adult

human brain, will be stepped up, " it said.

The tissues could also serve as " a mini organ " for use in studying

the cause of the Alzheimer's disease and developing vaccines, it said.

Embryonic stem cells are harvested by destroying a viable embryo, a

process that some people find unacceptable.

Riken said cortex tissues were also obtained from " induced

pluripotent stem cells, " which are similar to embryonic stem cells

but artificially induced, typically from adult cells such as skin

cells.

The research was led by Yoshiki Sasai at Riken Centre for Development

Biology in western Japan's Kobe.

The cultivated tissues look like minature mushrooms two millimetres

(0.08 inches) in diametre.

The team also succeeded in making cortex tissues from the embryonic

stem cells of mice.

Using mouse tissues, scientists confirmed they had formed a network

of neurons that properly respond to stimulus.

The tissues can also be selectively induced to different cortex types

controlling memories, visual sensation and other tasks.

The findings of the study were published in the November 6 online

journal Cell Stem Cell in the United States.