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Stem Cell Treatment To Cure the Most Common Cause of Blindness

Posted by Soulskill on from the i-can-see-clearly-now dept.

The Times Online reports that researchers from the Institute of Ophthalmology at University College London and Moorfields eye hospital have developed stem cell therapy that can treat age-related macular degeneration (AMD), the most common cause of blindness. They are currently moving the treatment through the regulatory approval process, and clinical trials are expected to start within two years. Quoting: "Under the new treatment, embryonic stem cells are transformed into replicas of the missing cells. They are then placed on an artificial membrane which is inserted in the back of the retina. ... [Professor Pete Coffey, director of the London Project to Cure Blindness] said the treatment would take 'less than an hour, so it really could be considered as an outpatient procedure. We are trying to get it out as a common therapy.'

10 of 126 comments (clear)

  1. Still a long way to go... by Anonymous Coward · · Score: 5, Informative

    IAAO (I am an Ophthalmologist).

    Although the article does not mention what kind of cells and membranes are transplanted and wether it is going to be used in exsudative or non-exsudative AMD I would assume that it's retinal Pigment Epithelium and Bruch's Membrane being used in wet (= exsudative) AMD.
    Therefore this seems to involve subretinal surgery, which is not a piece of cake and usually diminishes visual accuity.
    Previous attempts in this direction have already been done (macular rotation, retinal pigment epithelium transplants, etc.), results have not been all too gratifying.

    1. Re:Still a long way to go... by spineboy · · Score: 3, Informative

      IANAO IAAO (I am not an Opthomologist, I am an Orthopaedist)

      Anyway, I think the GP is suggesting that it's not just a little loss of visual acuity, but a lot, a whole lot. Maybe even enough to make it not worthwhile.
      If I recall correctly, the retina is kinda made backwards - the nerves are on top of the retinal layer. So one has to peel back the nerves to work on the layer underneath. I can't imagine that individual nerves like this at all.

      --
      ..........FULL STOP.
    2. Re:Still a long way to go... by bargainsale · · Score: 4, Informative

      IAAO too ...

      This is, I think, stem cell implantation subretinally for Geographic Atrophy, a.k.a "dry" macular degeneration. Potentially a big deal inasmuch as currently we have no treatment for this at all and it accounts for 90% of all macular degeneration.

      It involves major invasive surgery: "outpatient procedure" gives a highly misleading idea of what's involved. It doesn't mean any more than that you could get away with not admitting the patient to hospital, not that you could ever do it anywhere except in an operating theatre.

      Moorfields have lately developed a very bad habit of prematurely and misleadingly announcing "breakthroughs" in eye treatment, which I suspect is related to their own funding issues (they did this not long ago with some extremely misleading publicity about three patients with Leber's Amaurorosis they'd treated with gene therapy, not one of whom in fact showed measurable objective improvement in vision - not the impression the news reports tried to give.)

      Peng Khaw BTW is not a retinal expert (though Lyndon da Cruz certainly is; he was also involved in the publicity about the gene therapy, interestingly.)

      I'm sorry to say that I think this is the Moorfields spin machine in action.

      --
      Aberrations have appeared in my destiny prognostication engine!
    3. Re:Still a long way to go... by Anonymous Coward · · Score: 1, Informative

      IAAO IANAO (I am an Ophtalmologist, I am not an Orthopedist).

      You are correct. However, the structure affected in AMD is not directly the retina but Bruch's Membrane and the retinal pigment epithelium which both separate the retina from the underlying chorioid. (Vessels and subsequent retinal edema due to neovascularisation from the underlying chorioid to the retina is what is what is making exsudative AMD wet).
      In any way in order to place something between the chorioid and the retina you have to get past the retina (which is nerve tissue and does not like a lot of manipulation).

      Currently subretinal surgery for wet AMD is only exceptionally done, since it is technically challenging and results are very varying.
      Current treatment for wet AMD is either anti-VEGF Injections (Macugen,Lucentis,Avastin) to drive back the Vessels or PDT (photodynamic therapy = central retinal laser treatment after injecting Visudyne) to coagulate the vessels selectively.

      There currently is no treatment for dry AMD, however it progresses relatively slowly (years).
      If this were a treatment for dry AMD it would be something novel, however I would assume that it involves subretinal surgery which will carry in itself significant risk for further visual loss.

      So it might be something novel, but probably not a definitive and easy cure.

    4. Re:Still a long way to go... by bargainsale · · Score: 4, Informative

      No, that's incorrect.

      "Blindness" is being used in this context in a technical but generally accepted sense to mean vision so poor that you can't see the top letter on the eye chart with either eye. That's a grim state to be in, but most people who are "legally blind" like this are far from having no vision at all.

      In particular, Macular Degeneration hardly ever leads to the total blindness you are referring to.

      That doesn't mean it isn't a horrible crippling condition of course.

      --
      Aberrations have appeared in my destiny prognostication engine!
    5. Re:Still a long way to go... by ParadoxDruid · · Score: 4, Informative

      I recently met Pete Coffey, the lead scientist on this effort (he collaborates with scientists in a research group across the hall from mine), and attended his technical talk on this procedure. You are correct, they're transplanting retinal pigment epithelium. However, they've done experiments with both wet AMD and some preliminary work with reviving dry AMD. Very promising work; but yes, very involved surgery with a success rate of 75% even for ideal patients.

      --
      This statement is solely an opinion. Kindly take it as such in all cases.
  2. Re:Vampirism by CRCulver · · Score: 1, Informative

    Most of the medical profession believes that adult stem cells are more likely to offer cures than embryonic stem cells, so your complaint will prove a non-issue.

  3. Re:Straight to stem-cell cures? by juiceboxfan · · Score: 3, Informative

    ...Kurzweil suggests we'll all be in robot bodies before the century's end...

    I think I would rather have the robot augmentation than chance stem cells turning on me.

    From the above link;
    Then he was diagnosed with a brain tumor in 2005. That tumor, it turns out, grew out of the stem cells, obtained from at least two aborted fetuses, used in his brain.

    Besides can stem cells give you telescopic vision? Now that would be cool!

  4. Re:Vampirism by Anonymous Coward · · Score: 3, Informative

    Hi. Medical professional here. Do you have a source? Because that's not my thinking, or the thinking of most others I've discussed the issue with.

  5. Re:The Real Problem by lena_10326 · · Score: 2, Informative

    Responding because crying strawman or ad hominem incorrectly is something that highly irritates me. It also seems to be on the rise. The guy proposed a hypothetical future scenario and essentially made a slippery slope argument. That's not strawman. Strawman is inserting a new, similar argument and passing it off as the opponent's argument (a misrepresentation) and then arguing against that new argument.

    --
    Camping on quad since 1996.