Scientists make brain cells from pee
Unlike other stem cell technologies, the pee-based brain cells didn’t form tumors when implanted into rats
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The revolutionary ‘contact lens’ loaded with stem cells that restores sight - by helping the eye heal itself naturally
A ‘contact lens’ loaded with stem cells could be a way to naturally repair or retain sight. Scientists hope the biodegradable implant loaded with stem cells that then multiply will allow the body to heal the eye naturally.
Stem cells are the building blocks of tissue growth. They can transform into any other type of cell the body is built from and so should be able to repair everything from the brain to the heart. The scientists at the University of Sheffield who developed the implant now hope the new technique could help millions of people across the world retain or even regain - their sight.
The technology has been designed to treat damage to the cornea, the transparent layer on the front of the eye, which is one of the major causes of blindness in the world. With the new implant, by mimicking structural features of the eye, the researchers have developed a new method for producing very delicate thin membranes to help graft stem cells onto the eye itself.
Using a series of complex techniques, the researchers are able to make a disc of biodegradable material that can be fixed over the cornea. The disc is loaded with stem cells that then multiply, allowing the body to heal the eye naturally. Standard treatments for corneal blindness are corneal transplants or grafting stem cells onto the eye using a donated human membrane as a temporary carrier to deliver these cells to the eye.
But for some patients, the treatment can fail after a few years as the repaired eyes do not retain these stem cells, which are required to carry out repair of the cornea. A key feature of this new disc is that it contains small pockets to house and protect the stem cells, to keep them in the eye and also grouped together.
‘The disc has an outer ring containing pockets into which stem cells taken from the patient’s healthy eye can be placed,’ said Dr Ílida Ortega Asencio, from Sheffield’s Faculty of Engineering.
‘The material across the centre of the disc is thinner than the ring, so it will biodegrade more quickly allowing the stem cells to proliferate across the surface of the eye to repair the cornea.’
Without this constant repair, thick white scar tissue forms across the cornea causing partial or complete sight loss. The researchers said another advantage of the disc is that it is biodegradable and made from the same material already used in sutures, so it will not cause a problem in the body.Laboratory tests have shown that the membranes will support cell growth. As a result, clinical trials are expected to begin shortly in India, as the Sheffield scientists are working in conjunction with researchers at the LV Prasad Eye Institute in Hyderabad.
Commenting on the disc, Dr Frederick Claeyssens, lecturer in biomaterials at the University of Sheffield, said: ‘We also believe that the overall treatment using these discs will not only be better than current treatments, it will be cheaper as well.’
The research is published in the journal Acta Biomaterialia.
Woah.
Biocompatible sponge can be injected to deliver stem cells and drugs into the body
Biocompatible scaffolds, like those developed to stimulate the repair of heart tissue and bone and cartilage in the body, would normally need to be implanted surgically. Now bioengineers at Harvard University have developed a compressible bioscaffold that can be delivered via a syringe before popping back to its original shape inside the body. The material is also able to be loaded up with drugs or living cells that are gradually released as the material breaks down.
The injectable sponge is made up primarily of a seaweed-based jelly called alginate. It is actually a sponge-like gel that is formed through a freezing process called cryogelation. When the water in the alginate solution starts to freeze, pure ice crystals are formed and the surrounding gel becomes more concentrated as it sets. Later, the ice crystal melt to leave a network of large pores that allow liquids and large molecules to easily flow through it. Live cells can be attached to the walls of this network and large and small proteins and drugs can also be held within the alginate jelly itself.
Unlike other alginate gels that are brittle, using this method the researchers were able to produce a strong, compressible gel by carefully calibrating the alginate mixture and the timing of the freezing process.
The research team led by principal investigator David J. Mooney, the Robert P. Pinkas Family Professor of Bioengineering at the Harvard School of Engineering and Applied Sciences (SEAS), demonstrated that cells and drugs can be delivered into the body intact along with the sponge through a small bore needle. Once inside the body, the sponge returns to its original shape and gradually releases its cargo as it breaks down.
“What we’ve created is a three-dimensional structure that you could use to influence the cells in the tissue surrounding it and perhaps promote tissue formation,” explains Mooney. “The simplest application is when you want bulking. If you want to introduce some material into the body to replace tissue that’s been lost or that is deficient, this would be ideal. In other situations, you could use it to transplant stem cells if you’re trying to promote tissue regeneration, or you might want to transplant immune cells, if you’re looking at immunotherapy.”
Men who lose the ability to produce sperm after chemotherapy might one day be able to regain their fertility. That’s because, for the first time, infertility has been reversed in a male primate using an injection of stem cells.
Cancer drugs often work by destroying rapidly dividing cells, as these are a typical feature of cancer. Unfortunately, the drugs can also kill other rapidly dividing cells, including those that produce sperm. Some men choose to freeze sperm samples before therapy so they can use them for artificial insemination at a later date, but this is not an option for boys who have not yet reached puberty.
Kyle Orwig at the University of Pittsburgh School of Medicine in Pennsylvania may have a solution. He says that while boys don’t make sperm cells, they do possess “spermatogonial” stem cells that will eventually produce them.
To see if these stem cells could be used to restore fertility, Orwig and his team took samples of the cells from the testes of prepubescent and adult male rhesus macaques, and froze them. The monkeys were then given chemotherapy agents known to shut down sperm production. A few months later, the researchers injected each monkey’s own spermatogonial stem cells back into its testes.
Sperm production was re-established in nine of the 12 adult animals and started normally in three out of five prepubescent animals once they reached maturity. The resulting sperm were used to fertilise eggs and produce healthy embryos.
“I think this is the best option we have ever had,” says Renee Reijo Pera, director of Stanford University’s Center for Human Embryonic Stem Cell Research and Education, who wasn’t involved in the study. “I know a lot of people have thought about doing this before but no has ever been able to successfully demonstrate this in a clinical setting with a species genetically very similar to us.”
Orwig says there are some concerns that implanting stem cells could reintroduce cancer cells that may have been present in the original tissue. However, centres in the US and Europe are already banking testicular tissue for boys in the hope that new stem cell-based therapies will become available.
“In the most optimistic scenario our research suggests a man could have his own stem cells transplanted, giving him the opportunity to have children via natural intercourse,” Orwig says. It’s not yet ready for clinical translation, he says, “but it’s an important step forward”.
Journal reference: Cell Stem Cell, DOI: 10.1016/j.stem.2012.07.017
You guys, this is a pretty big deal.
Human embryo revealing the inner cell mass. Colour-enhanced image of a human embryo at the blastocyst stage opened to reveal the inner cell mass. These cells go on to form the embryo and can be harvested and cultured to give rise to embryonic stem (ES) cells.
Yorgos Nikas, Wellcome Images
Cellular biology porn!
Hey guys, abstractnerd here just wanted to introduce myself. I’m a new member of the We Speak For Earth team and I’ll be mainly covering topics related to Biology and Natural Sciences. I’m really excited to be a part of the team and helping to keep you guys up to date with the latest news and discoveries.
I’m currently in a Masters program in Biology and hope to get my Doctoral Degree in Biology as well; so needless to say Biology has become something of a passion for me.
I thought I’d start off by giving you guys the most current news in Biology and that’s the Nobel Prize that was awarded to Sir John B. Gurdon and Shinya Yamanaka “for the discovery that mature cells can be reprogrammed to become pluripotent”.
Stem cells are amazing. The fact that we all carry some of these undifferentiated cells in various parts of our body opens the door for a new branch of medicine. The success of this operation shows that it is possible. Transplant rejection could eventually become a non-issue. Having said that, being on the cutting edge means that this sort of therapy is still very prohibitively expensive.
We have stem cell sprays for burn victims and now this. Leave your thoughts on the state of regenerative medicine below.
Umbilical Cord Stem Cells Converted into Brain Support Cells
For the first time ever, stem cells from umbilical cords have been converted into other types of cells, which may eventually lead to new treatment options for spinal cord injuries and multiple sclerosis, among other nervous system diseases.
“This is the first time this has been done with non-embryonic stem cells,” says James Hickman, a University of Central Florida bioengineer and leader of the research group. ”We’re very excited about where this could lead because it overcomes many of the obstacles present with embryonic stem cells.”
Stem cells from umbilical cords do not pose an ethical dilemma because the cells come from a source that would otherwise be discarded. Another major benefit is that umbilical cells generally have not been found to cause immune reactions, which would simplify their potential use in medical treatments.
Beauty of Science: Neural Stem Cells Galore
Latin: Cellula Nervosa Precursoria
We all know at this point that Neurons are quite photogenic once you get it under the right lighting and scope, but what about their earlier years when they were just neural stem cells? Here’s a post I’ve been meaning to put together highlighting the beauty of the neural stem cell in swarms.
Neural stem cells (NSCs) are the self-renewing, multipotent cells that generate the main phenotypes of the nervous system.
In other words they’re the cells that form up from the start in your nervous system to turn into different types of neural related cells.
Beauty of Science: Neural Stem Cells Galore
Latin: Cellula Nervosa Precursoria
We all know at this point that Neurons are quite photogenic once you get it under the right lighting and scope, but what about their earlier years when they were just neural stem cells? Here’s a post I’ve been meaning to put together highlighting the beauty of the neural stem cell in swarms.
Neural stem cells (NSCs) are the self-renewing, multipotent cells that generate the main phenotypes of the nervous system.
In other words they’re the cells that form up from the start in your nervous system to turn into different types of neural related cells.
Scientists Produce First Endangered-Species Stem Cells
Scripps Research scientists produce first stem cells from endangered species. Cells could make it possible to improve reproduction and genetic diversity for some species, possibly saving them from extinction, or to bolster the health of endangered animals in captivity.
Stem cells are quickly becoming an important tool for human medical treatments, and researchers are betting they will also be a useful tool for zoo animals. They are working to create stem cell lines from zoo animals, for use in treating animal diabetes and other ailments as well as helping the animals reproduce.
The scientists have already created a “frozen zoo,” which contains different types of cells from every animal there, and now they are putting together a “stem cell zoo.”
“There are only two animals in it,” study researcher Inbar Friedrich Ben-Nun, of The Scripps Research Institute, said in a statement, “but we have the start of a new zoo, the stem cell zoo.”
Stem cells are prized, because they can be turned into any type of cell in the body, a characteristic called pluripotency. The cells can even be turned into sperm or egg cells, and used in assisted reproduction to make more individuals of the species.
Image Credit: San Diego Zoo
Dozens of people who were blinded or otherwise suffered severe eye damage when they were splashed with caustic chemicals had their sight restored with transplants of their own stem cells - a stunning success for the burgeoning cell-therapy field, Italian researchers reported Wednesday.
The treatment worked completely in 82 of 107 eyes and partially in 14 others, with benefits lasting up to a decade so far. One man whose eyes were severely damaged more than 60 years ago now has near-normal vision.
