Indian Scientists Grow Embryonic Eyes

June 25, 2017

This article by Lauren Tappan

A team of Indian scientists led by Dr. Indumathi Mariappan was able to grow complex eye-like organs in the lab by allowing the cells to organise themselves in three dimensions. The miniature eye closely resembles the developing eyes of an early-stage embryo. The eye-like structure consists of miniature forms of retina, cornea and eyelid. The results were published in the journalDevelopment.

“It took about four–six weeks for the eye-like structure to form from iPS cells. We then removed the cornea-like structure for further study,” says Dr. Mariappan from the Centre for Ocular Regeneration at the LV Prasad Eye Institute and the corresponding author of the paper.

The cornea has three layers — epithelium (outer layer), stroma (middle layer) and endothelium (inner layer). “All the three layers of the cornea were observed, indicating that the mini-cornea had developed correctly,” she says. “The cornea initially forms as a simple bubble-like structure which is very delicate to handle. It later matures to form a thick cornea-like structure over a period of 10-15 weeks.”

The corneal epithelial sheets that would be used for treating the damaged eyes were then grown in the lab using small pieces of the mini-cornea containing the epithelium and a portion of the stroma. The stem cells present in the tissue pieces proliferated and gave rise to a uniform sheet of epithelium of about 2.5 cm by 2.5 cm size.

Animal trials

The team is currently focusing on testing the usefulness of the corneal cells grown from iPS cells in restoring vision in animal models (rats). “We will soon be starting the animal experiments,” she says. Trials on human subjects will be considered if the animal experiments turn out to be safe and effective in restoring vision.

In treatment

In parallel, the researchers are also working on producing mini-retinal tissue and actively exploring iPS cell-derived retinal tissues for treating several retinal diseases such as age-related macular degeneration (AMD), retinitis pigmentosa and certain forms of congenital blindness seen in children and young adults.

Already, retinal cells grown using human embryonic stem cells and iPS cells are being tested in clincal trials in a few countries to treat retinal diseases.

For more info:
http://www.thehindu.com/todays-paper/tp-features/tp-sci-tech-and-agri/hyderabad-team-grows-miniature-eyes-using-stem-cells/article19097059.ece
Advertisements

Genable Technologies Ltd secures orphan drug designation by FDA for RP treatment

April 15, 2013

Genable Technologies Ltd gene therapy product GT038 has been granted orphan drug designation by the Federal Drug Administration (FDA) in the US for the treatment of Retinitis Pigmentosa. This provides Genable Technologies with seven years market exclusivity once GT308 has secured regulatory approval.



GT038 is currently undergoing formal pre-clinical assessments prior to commencing clinical studies in patients. 

For more info: http://businessandleadership.com/business/item/40556-irelands-genable/

http://www.genable.ie/technology/


Univ of Iowa Research Team Finds New Genetic Cause of Retinitis Pigmentosa

August 20, 2011

Combining the expertise of several different labs, University of Iowa researchers have found a new genetic cause of the blinding eye disease retinitis pigmentosa (RP) and, in the process, discovered an entirely new version of the message that codes for the affected protein.

The study, which was published online August 8 in the Proceedings of the National Academy of Sciences (PNAS) Early Edition, suggests that the mutation may be a significant cause of RP in people of Jewish descent. The findings also lay the groundwork for developing prevention and treatment for this form of RP using a combination of genetic testing, gene therapy and cell replacement approaches.

Using the latest DNA sequencing techniques to analyze the protein-coding regions of a single RP patient’s genome, the researchers found a mutation in a gene called MAK (male germ cell associated kinase). This gene had not previously been associated with eye disease in humans. However, examining tissue from donated eyes showed that MAK protein was located in the parts of the retina that are affected by the disease.

The researchers then generated induced pluripotent stem cells (iPSCs) from the patient’s own skin cells and coaxed these immature cells to develop into retinal tissue. Analyzing this tissue showed that the gene mutation caused the loss of the MAK protein in the retina.

“These new technologies have greatly enhanced our ability to find and validate disease-causing mutations, which is critical to our ability to progress to the next step of actually treating diseases like RP,” said Budd Tucker, PhD, UI assistant professor of ophthalmology and visual science and lead study author.

Based on the new work, the UI team hopes to explore gene therapy and cell replacement strategies as potential therapies for this form of RP.

http://www.uihealthcare.org/Newsarticle.aspx?id=225780

 


New Subretinal Stem Cell Treatment for Eye Disease

September 6, 2010

Ridgefield, CT (PRWEB) September 1, 2010
A new stem cell therapy is now available to eye patients using subretinal placement of adult stem cells. Patients with more severe eye problems may now have the opportunity to improve their sight and gain useful vision.

Dr Steven Levy is pleased to announce that The XCell-Center in Germany has begun a new treatment for eye patients using subretinal placement of adult stem cells for ophthalmic disease. Initial patients included an individual with Stargardts Disease, a type of hereditary retinopathy, and a patient with Age Related Macular Degeneration or AMD.

http://www.prweb.com/releases/2010/09/prweb4427444.htm


Researchers create retina from embryonic cells

June 14, 2010

Researchers in the US have successfully created a retina from human embryonic stem cells, which offers hope to millions with degenerative eye disorders.

Experts at the University of California Irvine created an eight-layer, early stage retina from human embryonic stem cells, which is the first ever three-dimensional tissue structure to be made from stem cells.

Study leader Hans Keirstead of the Reeve-Irvine Research Center and the Sue and Bill Gross Stem Cell Research Center at the facility, said the process also marks the first step towards the development of transplant-ready retinas to treat conditions such as retinitis pigmentosa and macular degeneration, a leading cause of blindness.


New Drugs Being Developed for Macular Degeneration

May 28, 2010

In 2005, two genetic studies of people with age-related macular degeneration (AMD)–the most common cause of blindness in people older than 65–made a surprising discovery. Research showed that defects in a gene that is an important regulator of parts of the immune system significantly increased risk of the disease. Scientists have since identified variants in several related genes that also boost risk, and which collectively account for about 50 to 60 percent of the heritability of the disorder.

Eye colors: Drusen, the yellow flecks in this image of the retina, are common in people with age-related macular degeneration. These flecks are made up of proteins involved in the part of the immune system called the complement system, which has also been implicated in the disease by genetic studies.
Credit: National Eye Institute

At the same time that researchers identified the harmful variation linked to AMD, Gregory Hageman, now at the University of Utah, identified a protective variant found in about 20 percent of the population. “That form is so incredibly protective that people with two copies are almost guaranteed not to develop the disease,” he says. Hageman founded Optherion, a startup based in New Haven, CT, and investigated how to translate the findings into new treatments. Optherion is now producing large quantities of an engineered version of the protein and doing preclinical safety and effectiveness testing–for example, examining whether the treatment can reduce ocular deposits in mice that lack the protein, says Colin Foster, Optherion’s president. He declined to estimate when the company will begin clinical trials of the drug.

http://www.technologyreview.com/biomedicine/25386/?ref=rss&a=f


Gene discovery may help hunt for blindness cure

May 6, 2010

LONDON (Reuters) – Scientists have discovered a gene mutation linked to the most common cause of blindness in the developed world, holding out the prospect of better treatments and perhaps eventually a cure.

British scientists said on Tuesday they had found six variants within the gene called Serping1 that were associated with age-related macular degeneration (AMD).

“Our findings add to the growing understanding of the genetics of age-related macular degeneration, which should ultimately lead to novel treatments for this common and devastating disease,” Sarah Ennis and Andrew Lotery of the University of Southampton reported in the Lancet journal.

http://www.calgaryherald.com/health/Gene+discovery+help+hunt+blindness+cure/868657/story.html#ixzz0n99w6KAq