Advances in Mammalian Hair Cell Generation Reported
Gaithersburg, MD — Scientists at the University of Michigan have regenerated hair cells in mammals, a landmark step in the goal of developing a treatment or therapy for restoring or partially restoring hearing. The researchers made adult guinea pigs grow new inner ear hair cells in the cochlea.

There are many different medical conditions that result in hearing loss and problems with balance. The most common reason is the absence or loss of functional hair cells in the inner ear. The generation of new hair cells offers a possible new approach in the treatment of hearing loss and balance dysfunction.

GenVec, Inc, a biopharmaceutical company, announced promising early data on its research into possible treatments for hearing loss and balance disorders, while a related study appeared in the June 2003 Journal of Neuroscience by Dr. Yehoash Raphael's laboratory at the University of Michigan. The researchers used the atonal homolog, MATH-1, and GenVec's proprietary technology to generate new hair cells in mature mammalian inner ears, which could ultimately have the potential for treating hearing loss. The MATH-1 gene is normally expressed within embryonic hair cells. A virus acted as a vehicle for the gene and was surgically implanted in the cochlea of 14 adult guinea pigs, including within non-sensory cells.

After 30 to 60 days, the researchers discovered hair cells growing in parts of the cochlea where hair cells are typically not found. Many of the new cells were outside the region where the hair cells normally grow—clearly showing that the treatment caused some non-sensory cells to be transformed into hair cells. Other immature cells were also found among existing hair cells, and it was unclear whether these were new or were recovering hair cells, but the chances seem good that they too were new hair cells. Even more encouraging, some nerve fibers were observed to be growing toward the new hair cells.

The researchers now want to determine if the regenerated hair cells function and are able to transmit sound signals to auditory neurons. They will also examine whether the procedure works for aging and deaf guinea pigs.

As with virtually all scientists working on the regeneration of hair cells, the researchers stress that this technology is a long way from being applied to humans, and many questions remain. For example, they don’t know if the new hair cells will survive, how they will be “wired” into the extant auditory system, and/or if they will function appropriately. This withstanding, the announcement still represents a large advance in moving toward the eventual goal of a possible genetic/pharmaceutical treatment for restoring or partially restoring hearing. As noted hearing scientist, Edwin Rubel, PhD, of the University of Washington, said in a recent Associated Press article (June 2, 2003), the results represent “a very, very important step...I wish I had done this study.”

“We are excited that GenVec's technology is now being tested by otology investigators for possible applications to treat diseases of the inner ear,” says Douglas E. Brough, director of Vector Sciences at GenVec. The company also has a research collaboration with Dr. Hinrich Staecker at the University of Maryland which is focused on balance disorders, according to the company.

In November 2001, GenVec reports that it entered into an exclusive license agreement with Baylor College of Medicine for the worldwide use of the MATH-1 (Mouse Atonal Homolog-1) and HATH-1 (Human Atonal Homolog-1) genes and technological know-how for gene therapy applications including, but not limited to, the treatment of deafness, osteoarthritis, and abnormal cell proliferation.

GenVec is a publicly held biopharmaceutical company focused on the development and commercialization of products that produce medically beneficial proteins at the site of disease. According to the company, it combines its patented gene transfer technologies with proprietary therapeutic genes to create product candidates, such as TNFerade™ for cancer, BIOBYPASS® for coronary artery disease, and AdPEDF for macular degeneration. The company is also reportedly collaborating with the US Government for the development of therapeutic vaccine candidates for HIV, malaria, dengue viruses, and SARS. Additional information on GenVec is available at its web site located at www.genvec.com. The research was supported by an NIDCD grant and information can be found on the NIDCD Web site at www.nidcd.com.

NCHA Allies with OSHA in Preventing Hearing Loss
Washington, DC — The National Hearing Conservation Association (NHCA) has become the latest in a growing number of organizations agreeing to work with the Occupational Safety and Health Administration (OSHA) to advance worker safety and health. NHCA formalized an alliance June 2 to set in motion a collaborative relationship with OSHA for the prevention of hearing loss caused by exposure to industrial and construction-related noise and other environmental factors in the workplace.

A key feature to the new alliance is the future development of a guide for hearing protection that will include a matrix for the use of hearing protection devices in various noise settings. Models on hearing conservation and hearing loss prevention programs for the construction and maritime industries will also be designed.

Through the alliance, OSHA and NHCA agree to “advance a culture of good hearing health by developing and implementing hearing conservation and hearing loss prevention programs.” NHCA members are said to benefit through information, guidance, and training geared to reducing exposures to hazards that result in hearing loss. Training courses will also be developed on noise and hearing loss prevention, including a “Train the Trainer Course” for toolbox talks and a program for vocational school populations.

NHCA and OSHA will also develop and disseminate information through various media, including their respective web sites. OSHA plans to create and update electronic assistance tools on its web site that will address noise and hearing conservation for general industry, as well as the construction and maritime industries.

“Millions of workers are exposed to high noise levels on the job,” says OSHA Administrator John Henshaw. “It's important that we do everything possible to eliminate the risk of hearing loss. The Alliance with NHCA allows us the opportunity to work with a wide range of professionals who are expert in hearing conservation and best practices.”

“We are delighted to have the opportunity to enter into this alliance agreement with OSHA,” says NHCA President Tim Bailey. “Our mission is to eliminate noise-induced hearing loss at work, home and play. This alliance will allow us to use our immense professional association's resources to develop recommended best practices, hearing conservation programs and practical guides for industry, with a special emphasis on the construction industry.”

For more information, visit http://www.osha.gov.

NIDCD/NICHD Study Shows That Infants Who Sleep on their Backs Less Prone to Ear Infections
Washington, DC — A team of researchers reports that infants who are placed to sleep on their backs are not at increased risk for health problems, and they are less likely to develop fevers, get stuffy noses, or develop otitis media (ear infection). The study, appearing in the Archives Of Pediatrics & Adolescent Medicine, was funded by the National Institute of Child Health and Human Development (NICHD) and the National Institute on Deafness and other Communication Disorders (NIDCD).

Placing infants to sleep on their backs has been found to reduce the risk of Sudden Infant Death Syndrome (SIDS) and it appears that the practice may confer specific benefits for infants’ health. “Placing infants to sleep on their backs not only reduces their risk of Sudden Infant Death Syndrome, but also appears to reduce the risk for fever, stuffy nose, and ear infections,” said Duane Alexander, M.D., director of the NICHD.

“Otitis media causes suffering in infants and young children, costs the American public an estimated $5 billion dollars per year, and results in overuse of antibiotics. The research showing that putting infants on their backs to sleep is saving lives is now revealing an outstanding additional benefit, the reduction of otitis media in infants," said James F. Battey, Jr., MD, PhD, director of the NIDCD.

BHI Makes Administrative Changes
Alexandria, Va — Mikael Worning, president of Oticon Inc. was unanimously elected president of the Better Hearing Institute (BHI) by the BHI Board. “I am honored to accept this leadership position within our industry,” says Worning. “The challenge presented itself at a good point for me and, I believe, for BHI. I intend to help BHI build on the success of the Physician Referral Development Program [see the February 2002 HR, p. 26], which is now established and operating well. Additionally, over the next several months, I will be guiding a structured assessment of the program and I think it is a natural point at which to consider other possibilities for BHI to carry out its educational and informational mandates. The whole field needs this communication, and the manufacturers want BHI to be as effective as it possibly can be in carrying the message of hearing health and hearing aids.”

The Physician Referral Development Program will continue under the direction of Dan Denston who has been involved with the program almost since its inception.