By Don C. Reed
What are your favorite sounds… I know one of mine.
It was Winter in Pennsylvania. I was out of work and hungry. Every day I would check out the Day Labor office and see if there was a couple hours work unloading a van for minimum wage. One week I made $8 dollars; the rent was $12.
But almost every day, I would head to the library, where they would loan you a headset and some music. And I would listen to the glorious Julie Andrews singing “I Could Have Danced All Night” from “MY FAIR LADY”, and for a little while, all my troubles went away. That last note, impossibly perfect, a divine scream.
What sounds most reverberate with you? The laughter of friends, the rustle of wind through the forest, the snarling inhalation of a Bengal tiger?
Imagine those sounds gone forever, leaving only perpetual silence…
Helen Keller, blind and deaf, was asked which condition was more difficult. Putting her fingers to the questioner’s lips, she could “hear”. She answered:
“The problems of deafness are deeper and more complex…than blindness. Deafness…is the loss of the most vital stimulus — voice that brings language, sets thoughts astir, and keeps us in the intellectual company of man…Blindness separates us from things; deafness separates us from people.” (1)
How big a problem are we talking about?
“Hearing loss is a permanent sensory disorder affecting over 278 million people worldwide. In the US… 20% suffer from this sensory deficit.
“Existing treatments aim at improving the symptoms of hearing loss, yet fail to reverse the main underlying (problem), loss of inner ear sensory hair cells.” (2)
Deep within the inner ear, inside the snail-shaped cochlea, are tiny organs with hair-like tips. Immersed in liquid, these hair cells (HC) transmit vibrations to the brain, which interprets the vibrations as sound.
We are born with a limited number of these cells, perhaps twenty thousand in each ear . As these die off — through old age, chemical poison, disease, or the blast of noise — our hearing diminishes. Lose enough hair cells, and we become deaf.
The humble chicken can regrow its hair cells; so can the silver dollar-sized zebrafish — but not us.
Hearing aids provide a limited degree of help, as do cochlear implants: better than nothing. But to regain the full range of hearing, the subtlety and grandeur of sound? Once lost, that is forever gone.
Or maybe not.
If you visit Stanford (and you should, for it is both a place of beauty and an educational environment like no other) look for the Lorry I. Lokey Stem Cell Research Building. Named after the legendary friend of science, Lorry Lokey, the facility was built with his help — and a $43 million grant from the California stem cell research program. (3)
But there are also two older Stanford labs, Stefan Heller’s and Alan Cheng’s, where hearing loss is fought with stem cells, each from very different angles.
Fighting against deafness, both Drs. Cheng and Heller received CIRM grants. (4)
Dr. Cheng hopes for progress with another source of hair cell. The utricle, a tiny organ inside the cochlea, is the center of balance, and gravity awareness. When the elevator floor drops out from underneath you, or when the fighter pilot swerves his jet, the utricle warns us. It has hair cells (HC) very similar to those which give us hearing, but with a crucial difference: for a short time, these hair cells regenerate.
“…the (balance) organs exhibit a limited capacity to regenerate HCs. We propose to characterize (hair cell) progenitors in… tissues from … mice and surgical patients.” –Alan Cheng, personal communication.
Cheng hopes to take tissues from the utricle and see if they can be encouraged to grow hair cells for hearing. Perhaps the signals which turn on the process during early growth can be turned on again.
And where does one get a flesh-and-blood utricle, from within the cochlea?
“If a patient has a tumor in the inner ear, and surgery must be done to remove the cochlea, he or she may choose to donate the tissues.” — Alan Cheng, ibid.
But what if we could grow a few million hair cells, developed from stem cells?
Dr. Stefan Heller has been working on this simple-sounding but very complicated task for more than ten years.
“The most exciting long-term goal…is to provide an abundant source of human inner ear progenitor cells that can… routinely create human hair cells…(This would) offer for the first time…the opportunity for detailed studies of this cell type…we envisage that (the research might) result in novel treatment strategies to cure deafness and potentially other inner ear diseases…” (5)
Both scientists’ lives are dedicated to the long struggle: against deafness.
“Curing hearing loss is a difficult endeavor and only a handful of laboratories worldwide are working on finding biological cures. Stanford aims to become one of the leading centers in the fight for a cure and plans are to further expand the existing group in the upcoming years.” (6)
I spoke with Dr. Cheng not long ago, and asked him: “How’s it going?”
“It’s going!”, he replied enthusiastically, “We see regrowth of hair cells in the mouse balance organs — and the balance function appears to improve, according to how many hair cells come back.”
Good luck, Drs. Cheng and Heller! (7)
And maybe the next time someone snaps their fingers, or turns on a noisy air conditioner — and you hear it — think of the California stem cell research program, which funds research to protect your hearing — or maybe bring it back, when it is gone.
How big a problem? “Approximately 15% of American adults (37.5 million!) aged 18 or over report some hearing loss .”(8)
ABOVE ALL — vote YES! on Proposition 14, to renew funding for the California Stem Cell Program: for more information, go to: www.caforcures.com
No funding, no research.
Don C. Reed is the author of “CALIFORNIA CURES”, and other books on stem cell research, from World Scientific Publishing, Inc.