March 9, 2016

expert reaction to two studies on stem cells and eyes

Two papers have been published in Nature examining the use of stem cells in eye research. The first reported stimulating the body’s own stem cells in the eye, in rabbits and separately in human infants, to promote regeneration of a surgically removed lens during treatment for cataracts. The second study used induced pluripotent stem cells and reported the ability to grow several types of eye tissue in a dish in a lab.

Dr. Dusko Ilic, Reader in Stem Cell Science, King’s College London, said:

“Both studies are remarkable accomplishments. Using induced pluripotent stem cells (iPSC), Nishida^ǂ et al are tackling ocular morphogenesis and are pushing limits in terms of what can be done in a laboratory dish. Although potentially translatable in the longer run, these findings are currently falling short of being able to lead to first-in-human trials in the near future, due to costs and safety.

“However, the study by Lin* et al is one of the finest achievements in the field of regenerative medicine until now. The basic science research led to the hypothesis that preserving and stimulating autologous stem cells in the eye might promote regeneration of a surgically removed lens. And indeed, their hypothesis was true. They proved it first by testing a new surgical approach in rabbits and primates before successfully treating 12 infants. It is science at its best.”

Prof. Graham McGeown, Deputy Head of the School of Medicine, Dentistry & Biomedical Sciences, Queen’s University Belfast, said:

“The study by Zhang* et al provides clear ‘proof in principle’ of an important new treatment for cataracts in children. They carried out a careful cellular and molecular study demonstrating the importance of Lens Epithelial Progenitor or Stem cells (LECs) as being able to regrow a healthy new lens following surgery to remove a cataract. This motivated the team to devise a new surgical technique for cataract removal that preserves the naturally existing LECs, which they then tested in children with congenital cataracts.

“Because the new treatment doesn’t involve introducing any new or non-native cells but simply seeks to preserve those normally found in the eye through delicate surgical technique, such an early trial was ethically justified. They showed that this new approach dramatically reduced the risk of sight damaging side effects when compared with the current ‘best practice’ treatment, which involves more destructive surgery followed by implantation of an artificial lens. It is unclear, however, whether this would be of benefit in adults with cataracts, for whom current surgical techniques are usually successful.”

* ‘Lens regeneration using endogenous stem cells with gain of visual function’ by Haotian Lin et al. published in Nature on Wednesday 9 March 2016. 

^ǂ ‘Co-ordinated ocular development from human iPS cells and recovery of corneal function’ by Ryuhei Hayashi et al. published in Nature on Wednesday 9 March 2016. 

Declared interests

Dr. Dusko Ilic: “I declare no conflict of interest.”

Prof. Graham McGeown: “I have no conflict of interest.”