Successfully 'thawing' a frozen human brain for the first time

Scientists have finally found a way to freeze the human brain, then 'thaw' it while still maintaining normal function .

This breakthrough was achieved by Zhi Cheng Shao's research group at Fudan University in Shanghai, China. Their new discovery could revolutionize the field of neurological disease research.

Frozen brain tissue was successfully revived for the first time. (Photo: Adobe Stock).

Normally, brain tissue will not survive freezing or thawing. This becomes a major barrier in medical research. To change this, the research team used human embryonic stem cells to grow organoids ( clusters of cells that can grow and proliferate in culture) in 3 weeks.

This allows neurons and neural stem cells to grow. Stem cells can become different types of brain cells with different functions. Then, scientists placed these organic substances - which have an average diameter of 4 mm - into various chemical compounds such as sugar, antifreeze, etc. This process aimed to determine which compounds were which. can help keep human brain tissue frozen and still growing after thawing.

After preserving these organic substances in liquid nitrogen for at least 24 hours, the team thawed them and looked for dead cells or monitored the growth of nerve cells over the next 2 weeks.

Based on cell death and growth rates, the scientific team selected the most promising compounds, testing different combinations in freeze-thaw tests on the new organoids.

The most successful combination includes methylcellulose, ethylene glycol, DMSO and Y27632, known as MEDY . Scientists think it blocks cell-killing factors, allowing tissues to freeze and thaw without problem.

To test the effectiveness of MEDY, the research team conducted a series of experiments on brain organoids of various ages, from 28 to more than 100 days old.

They found that the thawed organic matter remained nearly identical in shape, growth and function to the unfrozen organic matter, even after being frozen in the MEDY compound for 18 months. Similar results were observed on frozen human brain tissue in different brain regions.

Thawed brain tissues were visualized via immunofluorescence staining (MDHQ). (Photo: Weiwei Xue and colleagues).

To that end, the researchers took 3-millimeter blocks of brain tissue from a 9-month-old girl with epilepsy and placed them in MEDY, then froze and thawed them. This brain tissue maintained its structure before freezing and remained functional in laboratory culture for at least 2 weeks after thawing.

A breakthrough in freezing human brain tissue could help improve research on brain development in the laboratory, according to researchers from the University of Surrey and the University of Birmingham in the UK. health.

João Pedro Magalhães at the University of Birmingham said he was impressed that the team's method successfully prevented cell death and preserved their function. 'We clearly understand brain cells are fragile and sensitive to stress ,' he said.

Although this method still requires more research and the use of larger tissues, many are now predicting the ultimate result will be successful freezing of the entire human brain.

Some scientists even envision a future where terminally ill patients or astronauts traveling to distant star systems could have their brains cryopreserved. MEDY is 'a small step' towards that goal.