Stem Cells Prevent Blindness Suggests Human Trial. Hell Yeah!

Oh glory be!, the future is coming. There may be help for people suffering from macular-degeneration like my fucking Nana. Stem cells! Delicious stem cells may be able to help you Nana, hold the fuck on!


Human embryonic stem cells (hESCs) were first discovered thirteen years ago. Since then, they have shown incredible potential for therapeutic applications in conditions ranging from Alzheimer’s disease to diabetes – but no studies examining their effects in  humans  had ever been published. Yesterday, however, that all changed.

Marking one of the biggest milestones for the cells since their discovery, researchers yesterday published the first-ever results of a clinical trial that involved the transplantation of hESCs into the eyes of patients suffering from progressive forms of blindness. And the preliminary results look very good.

The study was designed to examine the safety of hESC-transplantation in two human patients with sight-threatening diseases. The first patient suffers from  age-related macular degeneration(AMD for short, age-related macular degeneration is the number one cause of blindness in people over 50), the second patient from  Stargardt’s macular dystrophy.

Both diseases are characterized by the gradual degeneration of a layer of cells in the eye known as the retinal pigment epithelium (RPE). If you’ve ever dissected a calf’s eye, you’ve seen the RPE – it’s the black-pigmented tissue lining the inside of the eye. As this cell layer wastes away, photoreceptors vital to eye sight are gradually lost, and blindness sets in. In the study published in  yesterday’s issue of  The Lancet  (no subscription required), a research team led by  stem cell pioneer Robert Lanzaexamined how safely hESCs could be transplanted into the RPE of these two patients.

It’s important to recognize that in early clinical trials, researchers are much more concerned with the safety of the treatment under investigation, and how well patients tolerate its administration, than they are with its efficacy. This trial was no different. Having said that, its findings are especially encouraging.

Four months after the transplants were performed, the researchers were able to verify that over 99% of the transplanted hESCs had successfully developed into RPE cells; neither patient had lost vision, as is typical of people with progressive blindness; and – perhaps most important of all – neither patient showed any signs of abnormal tissue growth (the risk of developing tumors has long been one of the biggest concerns attached to stem cell therapy).

In fact, both patients have described  improvements  to their vision. According to a piece published online in TIME, the patient suffering from macular dystrophy – a woman who goes by the assumed name “Rosemary” – has gone from seeing only vague hand gestures to being able to make out individual fingers; while Sue Freeman – the patient who suffers from AMD – is able to see seven more letters on a standard eye chart than she could before the treatment.

No serious, my Nana has been rocked by macular degeneration, and it’s a fucking bummer seeing her lose her vision. Here’s hoping there’s something to these studies. The Future, man! The future.