Work could eventually lead to cell transplants for people blinded by glaucoma, MS
Johns Hopkins researchers have developed a method to efficiently turn human stem cells into retinal ganglion cells, the type of nerve cells located within the retina that transmit visual signals from the eye to the brain. Death and dysfunction of these cells cause vision loss in conditions like glaucoma and multiple sclerosis.
"Our work could lead not only to a better understanding of the biology of the optic nerve, but also to a cell-based human model that could be used to discover drugs that stop or treat blinding conditions," says study leader Donald Zack, M.D., Ph.D., the Guerrieri Family Professor of Ophthalmology at the Johns Hopkins University School of Medicine. "And, eventually it could lead to the development of cell transplant therapies that restore vision in patients with glaucoma and MS."
The laboratory process, described in the journal Scientific Reports, entails genetically modifying a line of human embryonic stem cells to become fluorescent upon their differentiation to retinal ganglion cells, and then using that cell line for development of new differentiation methods and characterization of the resulting cells.
Using a genome editing laboratory tool called CRISPR-Cas9, investigators inserted a fluorescent protein gene into the stem cells' DNA. This red fluorescent protein would be expressed only if another gene was also expressed, a gene named BRN3B (POU4F2). BRN3B is expressed by mature retinal ganglion cells, so once a cell differentiated into a retinal ganglion cell, it would appear red under a microscope.
Next, they used a technique called fluorescence-activated cell sorting to separate out the newly differentiated retinal ganglion cells from a mixture of different cells into a highly purified cell population for study. The cells showed biological and physical properties seen in retinal ganglion cells produced naturally, says Zack.
Researchers also found that adding a naturally occurring plant chemical called forskolin on the first day of the process helped improve the cells' efficiency of becoming retinal ganglion cells. The researchers caution that forskolin, which is also widely available as a weight loss and muscle building supplement and is touted as an herbal treatment for a variety of disorders, is not scientifically proven safe or effective for treatment or prevention of blindness or any other disorder.
"By the 30th day of culture, there were obvious clumps of fluorescent cells visible under the microscope," says lead author Valentin Sluch, Ph.D., a former Johns Hopkins biochemistry, cellular and molecular biology student and now a postdoctoral scholar working at Novartis, a pharmaceutical company. Sluch completed this research at Johns Hopkins before transitioning to Novartis.
"I was very excited when it first worked," Sluch says. "I just jumped up from the microscope and ran [to get a colleague]. It seems we can now isolate the cells and study them in a pure culture, which is something that wasn't possible before."
"We really see this as just the beginning," adds Zack. In follow-up studies using CRISPR, his lab is looking to find other genes that are important for ganglion cell survival and function. "We hope that these cells can eventually lead to new treatments for glaucoma and other forms of optic nerve disease."
To use these cells to develop new treatments for MS, Zack is working with Peter Calabresi, M.D., professor of neurology and director of the Johns Hopkins Multiple Sclerosis Center.
This work was completed through the Wilmer Eye Institute's Glaucoma Center of Excellence and its Stem Cell Ocular Regenerative Medicine Center, of which Zack is co-director.
Study co-authors were Chung-ha Davis, Vinod Ranganathan, Kellin Krick, Russ Martin, Cynthia Berlinicke, Nicholas Marsh-Armstrong and Hai-Quan Mao of Johns Hopkins; and Jeffrey Diamond and Justin Kerr of the National Institute of Neurological Disorders and Stroke.
This work was supported by grants from the Maryland Stem Cell Research Fund under grant number 2014-MSCRFI-0774; the National Institutes of Health under grant numbers T32-90040730, 1RO1EY02268001, 5T32EY007143, 5P30EY001765 and R01EY023754; and unrestricted funds from Research to Prevent Blindness Inc., the Guerreri Family Foundation, and Mr. and Mrs. Robert and Clarice Smith.
Marin Hedin | EurekAlert!
Don't Give the Slightest Chance to Toxic Elements in Medicinal Products
23.03.2018 | Physikalisch-Technische Bundesanstalt (PTB)
North and South Cooperation to Combat Tuberculosis
22.03.2018 | Universität Zürich
Satellites in near-Earth orbit are at risk due to the steady increase in space debris. But their mission in the areas of telecommunications, navigation or weather forecasts is essential for society. Fraunhofer FHR therefore develops radar-based systems which allow the detection, tracking and cataloging of even the smallest particles of debris. Satellite operators who have access to our data are in a better position to plan evasive maneuvers and prevent destructive collisions. From April, 25-29 2018, Fraunhofer FHR and its partners will exhibit the complementary radar systems TIRA and GESTRA as well as the latest radar techniques for space observation across three stands at the ILA Berlin.
The "traffic situation" in space is very tense: the Earth is currently being orbited not only by countless satellites but also by a large volume of space...
An international team of researchers has discovered a new anti-cancer protein. The protein, called LHPP, prevents the uncontrolled proliferation of cancer cells in the liver. The researchers led by Prof. Michael N. Hall from the Biozentrum, University of Basel, report in “Nature” that LHPP can also serve as a biomarker for the diagnosis and prognosis of liver cancer.
The incidence of liver cancer, also known as hepatocellular carcinoma, is steadily increasing. In the last twenty years, the number of cases has almost doubled...
In just a few weeks from now, the Chinese space station Tiangong-1 will re-enter the Earth's atmosphere where it will to a large extent burn up. It is possible that some debris will reach the Earth's surface. Tiangong-1 is orbiting the Earth uncontrolled at a speed of approx. 29,000 km/h.Currently the prognosis relating to the time of impact currently lies within a window of several days. The scientists at Fraunhofer FHR have already been monitoring Tiangong-1 for a number of weeks with their TIRA system, one of the most powerful space observation radars in the world, with a view to supporting the German Space Situational Awareness Center and the ESA with their re-entry forecasts.
Following the loss of radio contact with Tiangong-1 in 2016 and due to the low orbital height, it is now inevitable that the Chinese space station will...
Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, provider of research and development services for OLED lighting solutions, announces the founding of the “OLED Licht Forum” and presents latest OLED design and lighting solutions during light+building, from March 18th – 23rd, 2018 in Frankfurt a.M./Germany, at booth no. F91 in Hall 4.0.
They are united in their passion for OLED (organic light emitting diodes) lighting with all of its unique facets and application possibilities. Thus experts in...
A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...
23.03.2018 | Event News
19.03.2018 | Event News
16.03.2018 | Event News
23.03.2018 | Materials Sciences
23.03.2018 | Agricultural and Forestry Science
23.03.2018 | Physics and Astronomy