cornea

Study shows sleep deprivation impairs stem cells in the cornea 

/ Esteban Cortez / 1 Comment

We spend around one third of our life sleeping—or at least we should. Not getting enough sleep can have serious consequences on many aspects of our health and has been linked to high blood pressure, heart disease and stroke. 

A study by the American Sleep Apnea Association found that some 70 percent of Americans report getting too little sleep at least one night a month, and 11 percent report not enough sleep every night. Over time that can take a big toll on your mental and physical health. Now a new study says that impact can also put you at increased risk for eye disease.  

The study published in the journal Stem Cell Reports, looked at how sleep deprivation affects corneal stem cells. These cells are essential in replacing diseased or damaged cells in the cornea, the transparent tissue layer that covers and protects the eye.  

Researchers Wei Li, Zugou Liu and colleagues from Xiamen University, China and Harvard Medical School, USA, found that, in mice short-term sleep deprivation increased the rate at which stem cells in the cornea multiplied. Having too many new cells created vision problems.  

They also found that long-term sleep deprivation had an even bigger impact on the health of the cornea. Sleep-deprived mice had fewer active stem cells and so were not as effective in replacing damaged or dying cells. That in turn led to a thinning of the cornea and a loss of transparency in the remaining cells.  

The cornea— the transparent tissue layer covering the eye—is maintained by stem cells, which divide to replace dying cells and to repair small injuries.

The findings suggest that sleep deprivation negatively affects the stem cells in the cornea, possibly leading to vision impairment in the long run. It’s not clear if these findings also apply to people, but if they do, the implications could be enormous.  

The California Institute for Regenerative Medicine (CIRM) is also heavily involved in searching for treatments for diseases or conditions that affect vision. We have invested almost $150 million in funding 31 projects on vision loss including a clinical trial with UCLA’s Dr. Sophie Deng targeting the cornea, and other clinical trials for age-related macular degeneration and retinitis pigmentosa. 

Shared with permission from International Society for Stem Cell Research. Read the source release here. 

Stem cell treatment restores man’s sight in right eye after 25 years

/ Yimy Villa / Leave a comment
James O’Brien, recipient of a stem cell treatment that restored the vision in his right eye

At 18 years old, there are several life-changing moments that young people look forward to. For some, it involves graduating from high school, starting college, and being able to cast a vote in an election. For others, this momentous occasion symbolizes the official start of adulthood.

For James O’ Brien, this milestone was marked by a rather unfortunate event where ammonia was thrown at his face in a random attack. As a result of this incident, the surface of his right eye was burned and he was left completely blind in his right eye.

Fast forward 25 years and thanks to an experimental stem cell treatment, James is able to see out of his right eye for the first time since the attack.

“Being able to see with both eyes – it’s a small thing that means the world. Basically I went from near-blindness in that eye to being able to see everything.” said O’Brien in a news release from Daily Heralds.

Dr. Sajjad Ahmad and a team of surgeons at the Moorfields Eye Hospital in London removed healthy stem cells from O’Brien’s left eye and grew these cells in a lab for months. After an adequate number of healthy stem cells from O’Briens left eye were grown, the surgeons then cut the scar tissue in his right eye and replaced it with the healthy stem cells.

They then waited a year after the procedure for the cells to settle down before inserting a cornea – which plays a key role in vision and focuses light – from a deceased donor.

“This is going to have a huge impact. A lot of these patients are young men so it affects their work, their lives, those around them. It’s not just the vision that drops, it’s the pain.” said Dr. Ahmad in the news release previously mentioned.

The procedure used took over 20 years to develop and Dr. Ahmad hopes to continue to develop the procedure for patients that have been blinded in both eyes by chemicals or have lost their vision through degenerative conditions.

CIRM has funded three clinical trials in vision loss to date. Two of these trials are being conducted by Dr. Henry Klassen for an eye condition known as retinitis pigmentosa and have shown promising results. The third trial is being conducted by Dr. Mark Humayun for another eye condition known as age-related macular degeneration (AMD) which has also shown promising results.

See video below for a news segment of James O’Brien on BBC News:

Pioneer’s 25-year struggle to treat blindness

/ Kevin McCormack / 1 Comment

Being a pioneer is never easy. You are charting unknown territory, tackling problems that have defeated others before you. You have to overcome so many obstacles that at times the challenge can seem insurmountable. But for those who succeed in reaching their goal, the rewards can be extraordinary.

Graziella Pellegrini, Center for Regenerative Medicine, University of Modena, Italy

Graziella Pellegrini, Center for Regenerative Medicine, University of Modena, Italy

Last month Italian researcher Graziella Pellegrini saw 25 years of work pay off when a treatment she developed to cure a form of blindness was given approval for sale by the European Commission.

This is quite an achievement as this means her treatment, called Holoclar, is among the first commercial stem therapies in the world (the first was Prochymal, which has been approved in Canada and New Zealand for the treatment of pediatric GVHD. This drug was developed by Osiris, which was led by our current President & CEO, Dr. Randy Mills.)

Holoclar uses stem cells to help stimulate the regrowth of a cornea. It can only be used for certain rare conditions, but that in no way diminishes its importance for patients or significance for the regenerative medicine field as a whole.

Nature recently sat down with Dr. Pellegrini to talk about her work, her struggle, and the many obstacles she had to overcome to get market approval for her work.

The interview makes for fascinating reading, and is a timely reminder why this kind of groundbreaking research never goes quite as quickly, or smoothly, as one would hope.

CIRM currently has a number of projects focused treating different causes of blindness on limbal cells (the kind Dr. Pellegrini worked on) and other forms of blindness; including a project to treat macular degeneration that has been approved for a clinical trial, and a therapy for retinitis pigmentosa that we hope will be approved for a clinical trial later this year.