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:2/12/2016)... ... February 12, 2016 , ... Young ... area, celebrates the beginning of the latest charity campaign in their community enrichment ... art. Donations to this worthy cause are currently being accepted at: http://artexpressioninc.org/ ...
(Date:2/12/2016)... FLA (PRWEB) , ... February 12, 2016 , ... Miami ... dental implants to their Miami dental office. Beginning in January, Miami Dental Specialists ... titanium. Miami Dental Specialists are the first office to be chosen by the dental ...
(Date:2/12/2016)... ... 12, 2016 , ... J Thomas & Associates Insurance Agency, ... to act as Agents of Change in the community, announces a new partnership ... to fulfill immediate needs and help them move into permanent housing. Donations to ...
(Date:2/12/2016)... (PRWEB) , ... February 12, 2016 , ... ... article about foods choices that promote eye health. These articles generally list between ... Water and health advocate Sharon Kleyne endorses every one of these lists and ...
(Date:2/12/2016)... ... 12, 2016 , ... Homeowners now have a next generation ... America‚Äôs leading brand of building products, has improved upon its industry-best array of ... version of the ColorView® Exterior Style and Color Selector. Created expressly for the ...
Breaking Medicine News(10 mins):
(Date:2/11/2016)... , Feb. 11, 2016 The primary goal ... future adoption patterns on the usage of liquid biopsy. ... following: - Timeframe of liquid biopsy adoption ... cfDNA and Evs—by organization type - Sample inflow to ... blood, saliva, stool, serum, and so on. - Correlation ...
(Date:2/11/2016)... NEW YORK , Feb. 11, 2016 ... and instruments commonly used in laboratories. These may range ... scale condensers. Laboratory glassware is made from borosilicate glass ... shock. Laboratory plasticware, on the other hand, started gaining ... that it was easier to replace glass with plastic ...
(Date:2/11/2016)... , Feb. 11, 2016  Governor Andrew M. Cuomo ... create 1,400 jobs throughout Western New York ... with the SUNY Polytechnic Institute, includes a major expansion ... in Buffalo , as well as ... facility in Dunkirk . The combined ...
Breaking Medicine Technology: