Scientists grow 5-week-old human brain

Scientists successfully grow human brain in lab

Scientists successfully grow human brain in lab

Growing brain tissue in a dish has been done before, but bold new research announced this week shows that scientists’ ability to create human brains in laboratory settings has come a long way quickly.

Researchers at the Ohio State University in the US claim to have developed the most complete laboratory-grown human brain ever, creating a model with the brain maturity of a 5-week-old foetus. The brain, which is approximately the size of a pencil eraser, contains 99 percent of the genes that would be present in a natural human foetal brain.

“It not only looks like the developing brain, its diverse cell types express nearly all genes like a brain,” Rene Anand, professor of biological chemistry and pharmacology at Ohio State and lead researcher on the brain model, said in a statement.

“We’ve struggled for a long time trying to solve complex brain disease problems that cause tremendous pain and suffering. The power of this brain model bodes very well for human health because it gives us better and more relevant options to test and develop therapeutics other than rodents.”

Anand turned to stem cell engineering four years ago after his specialized field of research – examining the relationship between nicotinic receptors and central nervous system disorders – ran into complications using rodent specimens. Despite having limited funds, Anand and his colleagues succeeded with their proprietary technique, which they are in the process of commercializing.

The brain they have developed is a virtually complete recreation of a human foetal brain, primarily missing only a vascular system – in other words, all the blood vessels. But everything else (spinal cord, major brain regions, multiple cell types, signalling circuitry is there). What’s more, it’s functioning, with high-resolution imaging of the brain model showing functioning neurons and brain cells.

The researchers say that it takes 15 weeks to grow a lab-developed brain to the equivalent of a 5-week-old foetal human brain, and the longer the maturation process the more complete the organoid will become.

“If we let it go to 16 or 20 weeks, that might complete it, filling in that 1 percent of missing genes. We don’t know yet,” said Anand.

The scientific benefit of growing human brains in laboratory settings is that it enables high-end research into human diseases that cannot be completed using rodents.

“In central nervous system diseases, this will enable studies of either underlying genetic susceptibility or purely environmental influences, or a combination,” said Anand. “Genomic science infers there are up to 600 genes that give rise to autism, but we are stuck there. Mathematical correlations and statistical methods are insufficient to in themselves identify causation. You need an experimental system – you need a human brain.”

The research was presented this week at the Military Health System Research Symposium.

 

Source:  sciencealert.com

Virus That Preys on Other Viruses

Virus That Preys on Other Viruses

Virus That Preys on Other Viruses

Viruses infect a wide range of plants and animals, and shows that they can even infect one another. If that seems surprising, no wonder: until a team of French researchers watched one virus invade another, hijacking its genetic machinery and making copies of its victim’s DNA, scientists didn’t even know this was possible.

The French team dubbed the virus’s virus Sputnik and called it a “virophage” to parallel “bacteriophage,” which is the name for a virus that infects bacteria. Sputnik is tiny, with only 18,000 genetic bases in its chromosome. Its victim, by contrast, is a large mamavirus that the scientists found in a Paris cooling tower, and contains about 1.2 million genetic bases. An infection by Sputnik sickens the mamavirus by interfering with its replication.

The discovery that even viruses can fall ill has reignited an old controversy—whether viruses are are actually alive or simply rogue bits of DNA that depend upon other organisms to reproduce. “There’s no doubt this is a living organism,” says Jean-Michel Claverie, a virologist at the the CNRS UPR laboratories in Marseilles, part of France’s basic-research agency. “The fact that it can get sick makes it more alive”.

And now that they know viruses can infect other viruses, the researchers say it could be possible to use virophages against the most harmful viruses, although they’re cautious about the idea. “It’s too early to say we could use Sputnik as a weapon against big viruses or to modify them,” says co-author Bernard La Scola, also at the University of the Mediterranean. “But phages are used to modify bacteria, so why not?”.

Source:  discovermagazine.com

Organs grown inside animals for the first time

Lab mouse

Researchers have had success growing organs in controlled lab environments, but repeating that feat inside a complex, messy animal body? That’s more than a little tricky. However, researchers at the University of Edinburgh have managed that daunting feat for the first time. They’ve grown thymus glands inside lab mice by “reprogramming” the genes in tissue-regenerating cells and partnering those with support cells. The team didn’t have to use scaffolds or other “cheats” to trigger the growth; it just injected the cells and waited. There weren’t even any obvious limitations. The organs were full size (unlike the baby-like results from some experiments), and they were just as efficient at producing virus-fighting T-cells as the real deal.

The catch, as you might have guessed, is the scale. Mice aren’t nearly as challenging to work on as humans, and the thymus is one of the simplest organs in any animal. It wouldn’t be nearly as easy to give you a new heart or lung. If the University keeps making progress, though, it could shake up the transplant process. Patients wouldn’t have to wait for donors whose tissues are good matches, and people who’ve lost much of their immune system (such as bone marrow transplant recipients) could rebuild faster. You won’t get on-demand organs any time soon, but the concept isn’t as far-fetched as it once was.

 

Source:  w.engadget.com

Human cartilage grown in lab

Engineers grow functional human cartilage in lab:

Engineers grow functional human cartilage in lab

Engineers grow functional human cartilage in lab

 

 

Researchers at Columbia Engineering announced that they have successfully grown fully functional human cartilage in vitro from human stem cells derived from bone marrow tissue. Their study, which demonstrates new ways to better mimic the enormous complexity of tissue development, regeneration, and disease.
“We’ve been able — for the first time — to generate fully functional human cartilage from mesenchymal stem cells by mimicking in vitro the developmental process of mesenchymal condensation,” says Gordana Vunjak-Novakovic, who led the study and is the Mikati Foundation Professor of Biomedical Engineering at Columbia Engineering and professor of medical sciences. “This could have clinical impact, as this cartilage can be used to repair a cartilage defect, or in combination with bone in a composite graft grown in lab for more complex tissue reconstruction.”

 

For more than 20 years, researchers have unofficially called cartilage the “official tissue of tissue engineering,” Vunjak-Novakovic observes. Many groups studied cartilage as an apparently simple tissue: one single cell type, no blood vessels or nerves, a tissue built for bearing loads while protecting bone ends in the joints. While there has been great success in engineering pieces of cartilage using young animal cells, no one has, until now, been able to reproduce these results using adult human stem cells from bone marrow or fat, the most practical stem cell source.
Vunjak-Novakovic’s team succeeded in growing cartilage with physiologic architecture and strength by radically changing the tissue-engineering approach.
The general approach to cartilage tissue engineering has been to place cells into a hydrogel and culture them in the presence of nutrients and growth factors and sometimes also mechanical loading. But using this technique with adult human stem cells has invariably produced mechanically weak cartilage. So Vunjak-Novakovic and her team, who have had a longstanding interest in skeletal tissue engineering, wondered if a method resembling the normal development of the skeleton could lead to a higher quality of cartilage.

 

Sarindr Bhumiratana, postdoctoral fellow in Vunjak-Novakovic’s Laboratory for Stem Cells and Tissue Engineering, came up with a new approach: inducing the mesenchymal stem cells to undergo a condensation stage as they do in the body before starting to make cartilage. He discovered that this simple but major departure from how things were usually? being done resulted in a quality of human cartilage not seen before.

 

Gerard Ateshian, Andrew Walz Professor of Mechanical Engineering, professor of biomedical engineering, and chair of the Department of Mechanical Engineering, and his PhD student, Sevan Oungoulian, helped perform measurements showing that the lubricative property and compressive strength — the two important functional properties — of the tissue-engineered cartilage approached those of native cartilage.
The researchers then used their method to regenerate large pieces of anatomically shaped and mechanically strong cartilage over the bone, and to repair defects in cartilage.

 

“Our whole approach to tissue engineering is biomimetic in nature, which means that our engineering designs are defined by biological principles,” Vunjak-Novakovic notes. “This approach has been effective in improving the quality of many engineered tissues — from bone to heart. Still, we were really surprised to see that our cartilage, grown by mimicking some aspects of biological development, was as strong as ‘normal’ human cartilage.”

 

The team plans next to test whether the engineered cartilage tissue maintains its structure and long-term function when implanted into a defect.

 

“This is a very exciting time for tissue engineers,” says Vunjak-Novakovic. “Stem cells are transforming the future of medicine, offering ways to overcome some of the human body’s fundamental limitations. We bioengineers are now working with stem cell scientists and clinicians to develop technologies that will make this dream possible. This project is a wonderful example that we need to ‘think as a cell’ to find out how exactly to coax the cells into making a functional human tissue of a specific kind. It’s emblematic of the progress being driven by the exceptional young talent we have among our postdocs and students at Columbia Engineering.”

 

Source:  sciencedaily.com

Lab grows self healing muscle tissue

Engineered muscle fibers are strong and could self-repair:

 

self healing muscles

self healing muscles

 

 

Scientists have grown living muscle in the lab that not only looks and works like the real thing, but also heals by itself – a significant step in tissue engineering.

Ultimately, they hope the lab-grown muscle could be used to repair damage in humans.

So far trials have tested this out in mice.

Duke University researchers say their success was down to creating the perfect environment for muscle growth – well-developed contractile muscle fibres and a pool of immature stem cells, known as satellite cells, that could develop into muscle tissue.

In tests, the lab-grown muscle was found to be strong and good at contracting and was able to repair itself using the satellite cells when the researchers damaged it with a toxin.

When it was grafted into mice, the muscle appeared to integrate well with the rest of the surrounding tissue and began doing the job required of it.

They say more tests are needed before they could move the work into humans.

Lead researcher Nenad Bursac said: “The muscle we have made represents an important advance for the field.

“It’s the first time engineered muscle has been created that contracts as strongly as native neonatal [newborn] skeletal muscle.”

UK expert in skeletal muscle tissue engineering Prof Mark Lewis, from Loughborough University, said: “A number of researchers have ‘grown’ muscles in the laboratory and shown that they can behave in similar ways to that seen in the human body. However, transplantation of these grown muscles into a living creature, which continue to function as if they were native muscle has been taken to the next level by the current work.”

There is great hope in the scientific community that stem cells, which can transform into any type of tissue, will transform regenerative medicine.

Scientists have already made mini-livers and kidneys in the lab using stem cells. Others have been looking at mending heart muscle with stem cells.

But cures and treatments are still some years away.

 

Source:  bbc.com