Navigation Links
Lab-grown, virus-free stem cells repair retinal tissue in mice
Date:1/23/2014

Investigators at Johns Hopkins report they have developed human induced-pluripotent stem cells (iPSCs) capable of repairing damaged retinal vascular tissue in mice. The stem cells, derived from human umbilical cord-blood and coaxed into an embryonic-like state, were grown without the conventional use of viruses, which can mutate genes and initiate cancers, according to the scientists. Their safer method of growing the cells has drawn increased support among scientists, they say, and paves the way for a stem cell bank of cord-blood derived iPSCs to advance regenerative medicine research.

In a report published Jan. 20 in the journal Circulation, stem cell biologist Elias Zambidis, M.D., Ph.D., and his colleagues describe laboratory experiments with these non-viral, human retinal iPSCs, created using the virus-free method Zambidis first reported in 2011.

"We began with stem cells taken from cord-blood, which have fewer acquired mutations and little, if any, epigenetic memory, which cells accumulate as time goes on," says Zambidis, associate professor of oncology and pediatrics at the Johns Hopkins Institute for Cell Engineering and the Kimmel Cancer Center. The scientists converted these cells to a status last experienced when they were part of six-day-old embryos.

Instead of using viruses to deliver a gene package to the cells to turn on processes that convert the cells back to stem cell states, Zambidis and his team used plasmids, rings of DNA that replicate briefly inside cells and then degrade.

Next, the scientists identified high-quality, multipotent, vascular stem cells generated from these iPSC that can make a type of blood vessel-rich tissue necessary for repairing retinal and other human material. They identified these cells by looking for cell surface proteins called CD31 and CD146. Zambidis says that they were able to create twice as many well-functioning vascular stem cells as compared with iPSCs made with other methods, and, "more importantly these cells engrafted and integrated into functioning blood vessels in damaged mouse retina."

Working with Gerard Lutty, Ph.D., and his team at Johns Hopkins' Wilmer Eye Institute, Zambidis' team injected the newly derived iPSCs into mice with damaged retinas, the light-sensitive part of the eyeball. Injections were given in the eye, the sinus cavity near the eye or into a tail vein. When the scientists took images of the mice retinas, they found that the iPSCs, regardless of injection location, engrafted and repaired blood vessel structures in the retina.

"The blood vessels enlarged like a balloon in each of the locations where the iPSCs engrafted," says Zambidis. The scientists said their cord blood-derived iPSCs compared very well with the ability of human embryonic-derived iPSCs to repair retinal damage.

Zambidis says there are plans to conduct additional experiments of their cells in diabetic rats, whose conditions more closely resemble human vascular damage to the retina than the mouse model used for the current study, he says.

With mounting requests from other laboratories, Zambidis says he frequently shares his cord blood-derived iPSC with other scientists. "The popular belief that iPSCs therapies need to be specific to individual patients may not be the case," says Zambidis. He points to recent success of partially matched bone marrow transplants in humans, shown to be equally as effective as fully matched transplants.

"Support is growing for building a large bank of iPSCs that scientists around the world can access," says Zambidis, although large resources and intense quality- control would be needed for such a feat. However, Japanese scientists led by stem-cell pioneer Shinya Yamanaka are doing exactly that, he says, creating a bank of stem cells derived from cord-blood samples from Japanese blood banks.


'/>"/>

Contact: Vanessa Wasta
wasta@jhmi.edu
410-614-2916
Johns Hopkins Medicine
Source:Eurekalert

Related medicine news :

1. Insulin-producing beta cells from stem cells
2. Tracing unique cells with mathematics
3. Number of cancer stem cells might not predict outcome in HPV-related oral cancers
4. Common blood cancer may be initiated by single mutation in bone cells
5. Not just clean but spotless -- Researchers show how cells tidy up
6. Stem Cells Could Prove Effective in Treating Brittle Bone Disease
7. Keeping stem cells pluripotent
8. Designer swiss-army-knife molecule captures RNA in single cells in their natural tissue environment
9. Study: Autophagy predicts which cancer cells live and die when faced with anti-cancer drugs
10. Platinum Soursop: The Natural Health Supplement Helps to Improve Cells Functions & Supports Immune System Now with 1 Extra Bottle Offer
11. NIH-created toxin can kill HIV-infected cells that persist despite treatment
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:2/23/2017)... Los Angeles, CA (PRWEB) , ... February 23, 2017 , ... ... the first two episodes of WE TV’s “Mama June: From Not to Hot,” which ... of TV notable, “Mama” June Shannon, known to millions from the 2012 reality television ...
(Date:2/23/2017)... Lawn, NJ (PRWEB) , ... February 23, 2017 ... ... specializing in thought leadership , media relations, content marketing, social media management, ... With several clients already in the state and in nearby New Hampshire, Massachusetts ...
(Date:2/23/2017)... ... February 23, 2017 , ... On April ... diverse symposium on “Doping in Sport: How the Culture Might Change,” ... Hampton LLP. The symposium will be held at Pepperdine University in Malibu, California. ...
(Date:2/23/2017)... ... February 23, 2017 , ... Pink Pig Publishing ... generations converge and explore the world from different perspectives. By providing a place ... to gain understanding, increase empathy, and find greater happiness. , "Our approach ...
(Date:2/23/2017)... (PRWEB) , ... February 23, 2017 , ... ... Phoenix, announced today that it will soon begin franchising throughout the U.S. starting ... mission to help bring the practice of meditation mainstream. Current Meditation will be ...
Breaking Medicine News(10 mins):
(Date:2/24/2017)... and Markets has announced the addition of the "Global Empty Capsules ... their offering. ... Empty Capsules Market is poised to grow at a CAGR of around ... This industry report analyzes the market estimates and forecasts ... presented in the research scope. The study provides historical market data for ...
(Date:2/24/2017)... Research and Markets has announced the addition of ... report to their offering. ... The latest research Dry eye Drugs Price Analysis and Strategies - 2016, ... The research answers the following questions: ... attributes? How are they positioned in the Global Dry eye market? ...
(Date:2/24/2017)...  In conjunction with DURECT Corporation,s (Nasdaq: ... you are invited to listen to a conference call ... Tuesday, March 14, 2017 at 4:30 pm Eastern Time ... webcast of the presentation will be available by accessing ... Relations."  If you are unable to participate during the ...
Breaking Medicine Technology: