Inner Ear Hair Cell-Like Cells from Human Embryonic Stem Cells

Dr. Heller

Dr. Heller

Dr. Heller discusses a recent paper from the Heller Lab, published in the journal Stem Cells & Development, and the work worldwide to regenerate human inner ear hair cells for the restoration of hearing:
The start to 2014 has been very exciting with many new advances to be published by our laboratory, but also by many of my colleagues.  Of course, each university will try to publicize these successes by generating lots of press, which seems to be the name of the game nowadays.  I admit that this is tremendously confusing for patients and parents of children with hearing loss and it can be frustrating because it could raise the hope that cures are just around the corner.  Unfortunately, there is still lots of work to be done.  
This said, I would also like to play the drums also a little bit by reporting a small but quite important paper by our own group that just got published a couple of days ago in the journal Stem Cells & Development.  There has been no glorifying press release about this story, mainly because it is not in a flashy journal but also because it reports lots of limitations of existing stem cell technology, particularly when it comes to generation of human inner ear cell types.  
Some readers might remember a 2012 Nature publication by a research group from Sheffield University, in the UK, reporting the restoration of some auditory function in laboratory animals with damaged auditory nerve by transplantation of human embryonic stem cell-derived nerve cells.  Buried in this paper was also a figure where the authors reported generation of, not very convincing looking, human sensory hair cells.  Our laboratory has also been working on generating human hair cells for almost 8 years now.  When the 2012 Nature paper came out, my postdoc Mohammad Ronaghi asked me why “his” hair cells (which looked a little more convincing than the published images) were not ready for publication.
Mohammad’s cells indeed were quite pretty and they were generated by coaxing human embryonic stem cells to show many signs of an inner ear phenotype.  Despite this peer-pressure, we decided to spend more energy on the project because we wanted a result that would be highly convincing – perhaps even by using the cells to restore auditory function in a sensory hair cell loss animal model.  Now it is 2014, and despite some additional steps, we did not reach this goal.  What we learned are several limitations to the use of human stem cell-generated inner ear cells that undoubtedly require lots of additional work in the upcoming years.  This work is difficult – we knew this before, but man, it is really difficult!  We decided to publish our findings at this point because we wanted to let other researchers know about our experience.  On the other hand, the results that we published are probably the best looking stem cell-generated human hair cell-like cells that have been generated thus far.  
In my mind, our publication is not the endpoint, but rather the beginning of multiple novel approaches to address the existing limitations.  It is a short paper but the product of a massive amount of work over many years.  Somehow, these are difficult papers for a laboratory, frustrating for the postdocs doing the work, and not the kind of publication that carry fame.  But in my mind, this is honest and hard work by the postdocs, students, and staff of my group and I highly appreciate their effort and sacrifices.  It is clear that much more work is needed, but on the other hand, the story needed to be told now so that new approaches and new directions can be tested.  It is a little like clearing the air, reshuffling, and taking off with new energy.
Perhaps the best news for the human approach comes from the European Union (surprise!).  Our laboratory is part of a consortium funded by the European Union to investigate in collaborative manner human stem cell applications for the treatment of hearing loss (  My hope for this concerted effort is that research will be faster, and that groups collaborate instead of compete with each other.  So far so good – we just had our kickoff meeting and first coordination meeting to get the planned research started.  Several of the limitations that hamper human stem cell applications are being addressed by this group effort, which makes me hopeful.



  1. Sam June 6, 2014 at 9:38 pm

    Looking forward to future developments. My hearing is good but I have virtually no vestibular function in either ear and it’s causing serious problems with vision during head movements.

  2. d vanoverbeke May 21, 2014 at 10:56 am

    I am a 17 yr. old with moderate/severe hearing loss in both ears. I first began wearing hearing aids at the age of 3. please consider me for any future studies regarding implanting inner ear hair cells. I am so looking forward to starting my young adult life hearing, and this gives me much hope. thank you for all the research you do.

  3. Robert May 18, 2014 at 2:12 am

    Dear Dr. Heller,
    Since my childhood, my left ear is deaf, my right ear has slight hearing loss but I cannot afford the cost for sure. If you need a person to experiment with this inner ear stem cell theraphy, I would allow myself to be that one in excahnge for free trial experimental treatment.. I’m just desperate to have a normal hearing. Please, message my email in case I won your favor.Thank you.

    • Kate Morris June 11, 2014 at 9:26 am

      Dear Robert, Thank you for your comment. Please note that the research is currently confined to the laboratory and it is likely to be a number of years before any treatments are found to be safe and effective for use in humans. But rest assured that our researchers are working very hard towards this goal.

  4. Dinesh May 6, 2014 at 6:11 pm

    Hello Dr. Heller, Can you let us know your expected time period to find a cure


  5. Clyde H Ball May 5, 2014 at 5:48 pm

    Dr. Heller,
    Thanks so much for the update. I am 71 years old and a Harley rider who lost all hearing in my left ear 4 years ago. The loss is in my inner ear due to a serious infection. The loss is devastating and has had a profound effect on my balance. But I still ride. There are those of us “out here” who just hang on to any info that may give us hope of ever hearing again. Please just do your best because we are waiting for a break through to enable us to live a “normal” life again. Three hearing specialists have told me that I will never hear from my left ear or get my balance back. But I have not given up. I am trying natural supplements at this time and can only hope. People who have never had this happen to them, might sympathize with us but they really don’t know what we go through on a daily basis. Good luck to you and your staff in your efforts.

  6. Matt Herold March 28, 2014 at 8:05 am

    Dr. Heller, thank you very much for the candid update. I am a hearing impaired individual (I lost most of my hearing about a decade ago) and I have followed your updates closely over the years. When I was working on Sand Hill road in 2006 I even e mailed you and asked if I could come meet you and see the lab and you graciously responded with an invitation which regretably I never followed up on. Anyway, thank you once again for this wonderful update. It is refreshing to read the unadulterated version of the latest developments because as you acknowledge the competition between various organizations pursuing this endeavor leads to a lot of information being published which does result in a lot of confusion, particuarly to people new to this issue.
    It is no understatement to say I pin my hopes on this research. I have been fortunate to not have suffered too many losses as so many others have with this condition (social connections, job, etc.) but as my hearing loss slowly progresses I think there will inevitably be some more dark days as a result of this condition. Restoring some or all of the hair cells and possibly curing the condition would simply open up a world to me that I’ve never known and which most people simply take for granted every day: the ability to interact and have a conversation with people.
    One final “shout out” – my aunt was recently misdiagnosed with a rare form of cancer by a doctor in San Jose. She was prepped for chemo. She decided to get a second opinion at Stanford, and thanks to the successful diagnosis of Carcinoid cancer by the physicians at Stanford she was taken off the plan for chemo and put on a biotherapy injection plan that is more effective for this cancer and is now entering a clinical trial at Stanford for this disease that will help her in her fight with this disease.
    Stanford truly is a world class institution that saves countess lives and leads the way in so many fields that greatly improve life for so many people. Thank you Stanford, Dr. Heller, your lab post docs and everyone for your efforts.

  7. -40db March 16, 2014 at 9:49 am

    Thank you for beeing honest to us suffers and thank you for your important research. We hope with the new ongoing research strategy many obstacles can be taken! Go for it!

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