Retinopathy of prematurity: could babies’ own vascular stem cells save their sight?

Published on 11 March 2011

What's the problem and who does it affect?

A lifetime of blindness: babies at risk

Retinopathy of prematurity – or ROP – is a major cause of vision loss and blindness in young children.^2,3 Babies who are born very prematurely, whose birth weight is very low, are most at risk.

Premature babies who need extra oxygen, to save their lives, are at an even higher risk of developing ROP if oxygen levels are not tightly controlled. Unfortunately, such tight control is not possible in many countries, because the resources needed are too expensive.

ROP often resolves spontaneously, leaving a baby’s vision unaffected. However, about one in ten babies with ROP develops severe disease, which threatens his or her sight.^2,4 If this is detected early enough, laser treatment can save the most important part of a baby’s vision – the sharp, central vision we need to look straight ahead.

However, laser treatment causes permanent loss of a baby’s peripheral vision and may induce short-sightedness. What’s more, it doesn’t always work, meaning some babies still go blind.

The incidence of ROP seems to be increasing, because improvements in neonatal care are giving very premature babies a better chance of surviving.4 New treatments are urgently needed.

What is the project trying to achieve?

Could stem cells save a babies' sight?

The researchers believe it may be possible to protect babies from ROP, and save their sight, by treating them with a special type of vascular stem cell. These cells, more accurately known as endothelial progenitor cells, can be obtained from a baby’s umbilical cord just after birth.

ROP is caused by blood vessels in the eye growing abnormally and causing damage to the retina, the light-sensitive inner lining of the eye. Laboratory evidence suggests stem cells might be able to help repair this damage.

The investigators now want to study samples of vascular stem cells taken, with the parents’ consent, from babies’ umbilical cords at birth. Some of the babies will be born prematurely and some at full term.

The researchers hope to find cells that may be suitable for use in a novel treatment of ROP. They are looking, for example, for cells that grow well in the laboratory, so they can obtain enough cells for treatment. They are also investigating which cells work best – how well they encourage the growth and repair of blood vessels from the eye and how changes in oxygen levels affect these processes.

What are the researchers' credentials?

The researchers have complementary expertise in clinical and laboratory research into both stem cells and diseases that affect the eye. They have a longstanding track record, which is well recognised internationally.

This project is being carried out in the Centre for Vision and Vascular Science at Queen’s University Belfast, which contains state-of-the art facilities and equipment. The centre has a long history of successful research into many of the leading causes of vision loss, such as diabetic retinopathy and age-related macular degeneration (AMD). Some of this work was funded by Action Medical Research and directed by members of this research team.

These highly qualified researchers, with their expert knowledge and well-equipped laboratory, are in the best possible position to succeed in this project.

Who stands to benefit from this research and how?

Vision of the future

The researchers aim to help premature babies who are at risk of losing their vision to ROP. The youngest, sickest and smallest premature babies are most at risk. That includes over 3,000 babies who are born more than 12 weeks early each year in the UK.⁵

The researchers hope their laboratory work will reveal whether vascular stem cells have the potential to repair damage to babies’ eyes and save their sight. If so, it is possible that in the future vascular stem cells could be taken from a baby’s own umbilical cord just after birth and then stored in a freezer in case treatment is needed.

The incidence of ROP seems to be increasing in many parts of the world.4 Too many children still have to face up to a lifetime of vision problems or even blindness. The demand for a better treatment, which saves more babies’ sight, without causing side effects, is high.

The impact of this work could be even further reaching. It is possible that these types of stem cells may eventually be used to save the sight of both children and adults who have other conditions that can cause blindness, including diabetes.

References

1. Gilbert C. Retinopathy of prematurity: a global perspective of the epidemics, population of babies at risk and implications for control. Early Hum Dev 2008; 84(2): 77-82.
2. National Eye Institute, National Institutes of Health, USA. Facts about retinopathy of prematurity (ROP). Website accessed 7 January 2011. http://www.nei.nih.gov/health/rop/rop.asp
3. Drack A. Retinopathy of Prematurity. Adv Pediatr 2006; 53:211-26.
4. MedlinePlus. Retinopathy of Prematurity. Website accessed 7 January 2011. http://www.nlm.nih.gov/medlineplus/ency/article/001618.htm
5. Office of National Statistics. Preterm births 2005. http://www.statistics.gov.uk/statbase/Product.asp?vlnk=14882 Website accessed 6th Jan 2011.